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Home/Mitsubishi/Eclipse/Mitsubishi Eclipse III (1999-2005)/Repair manual/Testing & Diagnostics/Engine Controls - Self-Diagnostics - 3.0L: Diagnosis
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Engine Controls - Self-Diagnostics - 3.0L: Diagnosis Mitsubishi Eclipse III

Testing & Diagnostics 7 illustrations ~63817 words

SYSTEM DIAGNOSIS

CAUTIONObtain radio anti-theft code before disconnecting battery.

Note. Engine management is controlled by an Engine Control Module (ECM) on vehicles with Manual Transaxle (M/T) and by a Powertrain Control Module (PCM) on vehicles with Automatic Transaxle (A/T). ECM/PCM diagnostic memory is retained by direct power supply from battery. Memory is not erased by turning ignition switch to LOCK position, but it will be erased if battery or ECM/PCM is disconnected.

ECM/PCM includes On Board Diagnostics II (OBD-II) software designed to monitor emission system over the life of the vehicle. On OBD-II, the Malfunction Indicator Light (MIL) will illuminate only for emission system-related faults. Most of these faults will not cause driveability problems and would go unnoticed by the driver were it not for the MIL. When MIL illuminates, a DTC will be stored. The ECM/PCM may also store DTCs that do not illuminate the MIL. These may be DTCs for faults that no longer exist, provisional codes or for faults that are not emission system-related. DTCs may be retrieved using the manufacturer's Multi-Use Tester-II (MUT-II) Scan Tool (MB991502) or a compatible generic scan tool. See ENTERING ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.

ECM/PCM monitors several different engine control system circuits. If an abnormal input signal occurs, the ECM/PCM will store it in memory as either a provisional code or DTC. A specific DTC indicates a particular system failure, but does not indicate the cause of failure is necessarily within that system. Most faults require that the malfunction be detected during 2 different trips before the MIL is illuminated. For DTCs that use two-trip detection logic, the first occurrence of the fault will store a provisional code. The second occurrence of the fault will set a DTC and illuminate the MIL.

For certain system or component failures, ECM/PCM will enter fail-safe function (limp-in mode). In fail-safe mode, ECM/PCM will substitute default values for the faulty component or system.

Each circuit or system monitored by ECM/PCM has particular engine and driving conditions that must be met before ECM/PCM will monitor it. These conditions are the code set criteria (DTC set conditions). Due to differences in code set criteria, some circuits or systems are monitored almost continuously while others may not be monitored at all during a particular drive cycle. After a repair, it is necessary to run the vehicle under conditions that meet code set criteria in order to verify the repair. This is best done by following the drive cycle related to the DTC. To verify a misfire or fuel trim repair, it is also necessary to operate the vehicle in conditions similar (engine speed, engine load, engine temperature, etc.) to those when the misfire occurred. These conditions are recorded as freeze frame data. Check freeze frame data before erasing DTCs, as freeze frame data will also be erased.

Readiness Test Status

During different parameters of engine operation, the ECM/PCM monitors and runs tests on various inputs, outputs and system functions. There are 6 monitors. One monitor (Other Monitor) passively monitors for shorts, grounds and out of range parameters. It runs continuously. The other 5 monitors actively test different systems and will only run when very specific engine operating conditions have been met. Those monitors may or may not run during any given drive cycle. These 5 monitors have a system readiness test to show whether the particular monitor has been run or not. For additional information on drive cycles, see VERIFYING REPAIRS . A system related DTC cannot set until its monitor has run successfully and readiness test status indicates COMPLETE.

When DTCs are cleared, each readiness test status is set to INCOMPLETE or NOT READY. To complete readiness test status, OBD-II drive cycles related to all on-board diagnostic items should be carried out. See OBD-II DRIVE CYCLES . If vehicle is normal, readiness test status will complete by carrying out OBD-II drive cycle once. Scan tool will then read COMPLETE. Generic scan tool will read READY. If ECM/PCM detects a malfunction, OBD-II drive cycle must be carried out again before readiness test status will complete. Once readiness test status is complete, ECM/PCM can be checked for DTCs.

Intermittent Diagnostic Trouble Codes

If DTC was set and DTC diagnostic procedure does not locate fault, problem is intermittent. Most intermittent malfunctions occur from vibration, temperature change, moisture change and poor connections. Try to determine under what specific conditions problem occurs. Try to duplicate those conditions while monitoring circuit suspected of being faulty with data recorded function of scan tool. The following additional checks may assist in identifying a possible intermittent problem

  1. Check Any Pertinent Technical Service Bulletin (TSB)
  2. Visually inspect related harness connectors for broken, bent, pushed out or corroded terminals.
  3. Visually inspect related harness for chafed, pierced or partially broken wires.
  4. Wiggle suspected wire(s) or vibrate suspected component.
  5. Apply heat and/or humidity to suspected component.

Provisional DTC

Provisional DTCs are set only during a single drive cycle. PCM will detect some malfunctions and set DTCs in memory but may not turn on the MIL. Provisional DTCs do not necessarily indicate a failure of a component or system. If a component or system fails for 2 drive cycles, a hard fault will be stored. See HARD FAILURES . For additional information on provisional DTCs, see VERIFYING REPAIRS .

VISUAL INSPECTION

Most driveability problems in the engine control system result from faulty wiring, poor electrical connections or leaking air and vacuum hose connections. To avoid unnecessary component testing, perform a visual inspection before beginning self-diagnostic tests.

ENTERING ON-BOARD DIAGNOSTICS

Note. DO NOT skip any steps in self-diagnostic tests or incorrect diagnosis may result. Ensure self-diagnostic test applies to vehicle being tested.

Using Scan Tool

  1. Refer to manufacturer's operation manual for instructions in use of scan tool. Before entering on-board diagnostics, see «SERVICE PRECAUTIONS»(ref-135484-S26271293172002022200000). Locate Data Link Connector (DLC) under instrument panel, near steering column. see scheme 11
  2. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Read and record scan tool self-diagnostic output. Proceed to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-135484-S06660038382002022200000). If scan tool will not communicate with ECM/PCM, diagnose communication concern. See «SCAN TOOL COMMUNICATIONS»(ref-135484-S20471678632002120400000). Turn ignition switch to LOCK position before disconnecting scan tool.

TWO-TRIP DTC MALFUNCTION

When a malfunction initially occurs, DTC will be temporarily stored in PCM memory, but MIL on instrument panel will not illuminate. The second time malfunction is detected, MIL on instrument panel will illuminate, provided ignition is turned off and then back on after first malfunction was detected. This applies to specific DTCs.

CLEARING DIAGNOSTIC TROUBLE CODES

CAUTIONAll data will be lost when DTCs are cleared. Before clearing DTCs, record data that may be needed later, such as freeze frame data.

Note. Obtain radio anti-theft code before disconnecting battery. When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle.

Note. A drive cycle is when engine goes from start to stop and component is monitored in-between. The component's code set criteria must be met while the engine is operating before it will be monitored. Due to this, component may not be monitored every engine start-to-stop cycle.

To clear DTCs using a scan tool, refer to owner's manual supplied with scan tool. If scan tool is not available, DTCs may be cleared by disconnecting negative battery cable or ECM/PCM for a few minutes. Reconnect negative battery cable. Start and warm up engine. Run vehicle through appropriate drive cycle(s). See VERIFYING REPAIRS . Check for DTCs to confirm repair.

Note. A drive cycle is when engine goes from start to stop and component is monitored in-between. The component's code set criteria must be met while the engine is operating before it will be monitored. Due to this, component may not be monitored every engine start-to-stop cycle.

MALFUNCTION INDICATOR LIGHT DIAGNOSIS

Note. For terminal identification, see appropriate illustration under CONNECTOR IDENTIFICATION . For circuit and wire color identification, see WIRING DIAGRAMS article.

Troubleshooting Hints

The most likely causes are

  1. Burnt-Out Bulb
  2. Defective MIL Circuit
  3. ECM/PCM Failed

Testing

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. set scan tool to the data reading mode for data list item 16: POWER SUPPLY VOLTAGE. Battery voltage should exist. If battery voltage exists, go to next step. If battery voltage does not exist, check for battery voltage at ECM/PCM. See «SYSTEM & COMPONENT TESTING»(ref-135493) article.
  2. Turn ignition switch to LOCK position. Remove instrument cluster and check for burned out MIL bulb. For removal and installation procedures, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. If bulb is okay, go to next step. If bulb is faulty, replace bulb.
  3. Remove instrument cluster. For removal and installation procedures, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Disconnect combination meter (instrument cluster) harness connector C-41. Check combination meter harness connector C-41 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it.
  4. Turn ignition switch to ON position. Measure voltage between ground and combination meter harness connector C-41 terminal No. 52. Battery voltage should exist. If battery voltage exists, go to next step. If battery voltage does not exist, repair open in circuit between combination meter and ignition switch.
  5. Turn ignition switch to LOCK position. Reconnect combination meter harness connector C-41. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it.
  6. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 22 or PCM harness connector C-52 terminal No. 22. Battery voltage should exist. If battery voltage exists, replace ECM/PCM. If battery voltage does not exist, repair open in circuit between combination meter harness connector C-42 terminal No. 52 and ECM harness connector C-51 terminal No. 22 or PCM harness connector C-52 terminal No. 22.

The most likely causes are

  1. Defective MIL Circuit
  2. ECM/PCM Failed
  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, check for stored DTCs. See «ENTERING ON-BOARD DIAGNOSTICS»(ref-135484-S09381641242002022200000) under SELF-DIAGNOSTIC SYSTEM. If no DTCs are present, go to next step. If DTCs are present, record all DTCs and go to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-135484-S06660038382002022200000) .
  2. Turn ignition switch to LOCK position. Remove instrument cluster. For removal and installation procedures, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Disconnect combination meter (instrument cluster) harness connector C-41. Check for continuity between ground and combination meter harness connector C-41 terminal No. 41. If continuity does not exist, replace ECM/PCM. If continuity exists, check connectors between combination meter and ECM/PCM for loose, damaged or corroded terminals. If problem exists, repair it. If problem does not exist, repair short to ground in circuit between combination meter harness connector C-41 terminal No. 41 and ECM harness connector C-51 terminal No. 22 or PCM harness connector C-52 terminal No. 22.

SCAN TOOL COMMUNICATIONS

Note. For terminal identification, see appropriate illustration under CONNECTOR IDENTIFICATION . For circuit and wire color identification, see WIRING DIAGRAMS article.

The most likely causes are

  1. Malfunction Of The DLC
  2. Damaged Harness
  1. Turn ignition switch to LOCK position. Measure voltage between ground and DLC terminal No. 16. Battery voltage should exist. If battery voltage exists, go to next step. If battery voltage does not exist, check connectors between DLC and power supply for loose, damaged or corroded terminals. If problem exists, repair it. If problem does not exist, repair open in circuit between DLC and power supply.
  2. Check for resistance between ground and DLC terminal No. 4, then terminal No. 5. If resistance is less than 2 ohms at both terminals, replace scan tool. If resistance is 2 ohms or more at one or both terminals, repair open in appropriate circuit(s) between ground and DLC.

The most likely causes are

  1. No Power Supply To ECM/PCM
  2. Defective Ground Circuit Of ECM/PCM
  3. Improper Communication Line Between ECM/PCM & Scan Tool
  4. Open Circuit Between ECM/PCM & DLC
  5. ECM/PCM Failed
  1. Turn ignition switch to LOCK position. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it.
  2. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem exists, repair it. If problem does not exist, check for open or short to ground in circuit between DLC terminal No. 7 and ECM harness connector C-62 terminal No. 85 or PCM harness connector C-59 terminal No. 85. If problem exists, repair circuit between DLC terminal No. 7 and ECM harness connector C-62 terminal No. 85 or PCM harness connector C-59 terminal No. 85 as necessary. If problem does not exist, repair circuit to power supply as necessary.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

Note. DTCs can only be retrieved by using a scan tool. See ENTERING ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.

When Diagnostic Trouble Code (DTC) is obtained, refer to appropriate DTC test procedure under DIAGNOSTIC TESTS .

DTC (1)Description
P0101Volume Airflow Circuit Range/Performance Problem
P0102Volume Airflow Circuit Low Input
DTC P0106 (2)Barometric Pressure Circuit Range/Performance Problem
P0107Barometric Pressure Circuit Low Input
P0108Barometric Pressure Circuit High Input
P0111Intake Air Temperature Circuit Range/Performance Problem
DTC P0112Intake Air Temperature Circuit Low Input
DTC P0113Intake Air Temperature Circuit High Input
P0116Engine Coolant Temperature Circuit Range/Performance Problem
P0117Engine Coolant Temperature Circuit Low Input
P0118Engine Coolant Temperature Circuit High Input
P0121Throttle Position Sensor Circuit Range/Performance Problem
P0122Throttle Position Sensor Circuit Low Input
P0123Throttle Position Sensor Circuit High Input
DTC P0125Insufficient Coolant Temperature For Closed Loop Fuel Control
P0128Coolant Thermostat Malfunction
P0132Heated Oxygen Sensor Circuit High Voltage (Bank 1 Sensor 1)
P0133Heated Oxygen Sensor Circuit Slow Response (Bank 1 Sensor 1)
P0134 (2)Heated Oxygen Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
P0135Heated Oxygen Sensor Heater Circuit (Bank 1 Sensor 1)
P0137Heated Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 2)
P0138Heated Oxygen Sensor Circuit High Voltage (Bank 1 Sensor 2)
P0139Heated Oxygen Sensor Circuit Slow Response (Bank 1 Sensor 2)
P0141Heated Oxygen Sensor Heater Circuit (Bank 1 Sensor 2)
P0152Heated Oxygen Sensor Circuit High Voltage (Bank 2 Sensor 1)
P0153Heated Oxygen Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0154 (2)Heated Oxygen Sensor Circuit No Activity Detected (Bank 2 Sensor 1)
P0155Heated Oxygen Sensor Heater Circuit (Bank 2 Sensor 1)
P0157Heated Oxygen Sensor Circuit Low Voltage (Bank 2 Sensor 2)
P0158Heated Oxygen Sensor Circuit High Voltage (Bank 2 Sensor 2)
P0159Heated Oxygen Sensor Circuit Slow Response (Bank 2 Sensor 2)
P0161Heated Oxygen Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
P0171System Too Lean (Bank 1)
P0172System Too Rich (Bank 1)
P0174System Too Lean (Bank 2)
P0175System Too Rich (Bank 2)
P0181Fuel Temperature Sensor Circuit Range/Performance
P0182Fuel Temperature Sensor Circuit Low Input
P0183Fuel Temperature Sensor Circuit High Input
P0201, P0203, P0205Injector No. 1 Circuit Malfunction, Injector No. 3 Circuit Malfunction, Injector No. 5 Circuit Malfunction
P0202, P0204, P0206Injector No. 2 Circuit Malfunction, Injector No. 4 Circuit Malfunction, Injector No. 6 Circuit Malfunction
P0300Random Misfire Detected
P0301-P0306Cylinders No. 1-6 Misfire Detected
P0325Knock Sensor Circuit
P0335Crankcase Position Sensor Circuit
P0340Camshaft Position Sensor Circuit
P0401Exhaust Gas Recirculation Flow Insufficient Detected
P0403Exhaust Gas Recirculation Control Circuit
P0421Warm Up Catalyst Efficiency Below Threshold (Bank 1)
P0431Warm Up Catalyst Efficiency Below Threshold (Bank 2)
P0441Evaporative Emission Control System Incorrect Purge Flow
P0442Evaporative Emission Control System Leak Detected (Small Leak)
P0443Evaporative Emission Control System Purge Control Valve Circuit
P0446Evaporative Emission Control System Vent Control
P0451Evaporative Emission Control System Pressure Sensor Range/Performance
P0452Evaporative Emission Control System Pressure Sensor Low Input
P0453Evaporative Emission Control System Pressure Sensor High Input
P0455Evaporative Emission Control System Leak Detected (Gross Leak)
P0456Evaporative Emission Control System Leak Detected (Very Small Leak)
P0461Fuel Level Sensor Circuit Range/Performance
P0500Vehicle Speed Sensor Malfunction (M/T)
P0506Idle Control System RPM Lower Than Expected
P0507Idle Control System RPM Higher Than Expected
P0551Power Steering Pressure Sensor Circuit Range/Performance
P0705 (3)Park/Neutral Position Switch - Open Or Short Circuit
P0712 (3)Transmission Fluid Temperature Sensor Circuit - Shorted
P0713 (3)Transmission Fluid Temperature Sensor Circuit - Open
P0715 (3)Input Shaft Speed Sensor Circuit - Open/Shorted
P0720 (3)Output Shaft Speed Sensor Circuit - Open/Shorted
P0731 (3)1st Gear Ratio Incorrect
P0732 (3)2nd Gear Ratio Incorrect
P0733 (3)3rd Gear Ratio Incorrect
P0734 (3)4th Gear Ratio Incorrect
P0736 (3)Reverse Gear Ratio Incorrect
P0741 (3)Torque Converter Clutch Solenoid - Defective
P0742 (3)Torque Converter Clutch Circuit Stuck On
P0743 (3)Torque Converter Clutch Circuit - Open/Shorted
P0753 (3)Low-Reverse Solenoid Circuit - Open/Shorted
P0758 (3)Underdrive Solenoid Circuit - Open/Shorted
P0763 (3)Second Solenoid Valve Circuit - Open/Shorted
P0768 (3)Overdrive Solenoid Valve Circuit - Open/Shorted
P1400Manifold Differential Pressure Sensor Circuit Malfunction
P1500Generator FR Terminal Circuit Malfunction
P1603 (2)Battery Backup Circuit Malfunction
P1610Immobilizer Malfunction
P1751 (3)A/T Control Relay Circuit - Open/Shorted To Ground
(1) All DTCs use two-trip fault detection logic unless otherwise specified. If DTC is for a fault that may affect emissions, MIL will also illuminate. (2) This DTC will set first trip fault is detected. (3) For diagnostic procedures, see appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.
(1)All DTCs use two-trip fault detection logic unless otherwise specified. If DTC is for a fault that may affect emissions, MIL will also illuminate.
(2)This DTC will set first trip fault is detected.
(3)For diagnostic procedures, see appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.

DIAGNOSTIC TROUBLE CODE INDEX

DTC Set Conditions

  1. Check condition is when TP sensor output voltage is 1.5 volts or more and engine speed is more than 2000 RPM. Judgement criteria is when VAF sensor output frequency is 60 Hz or less for 2 seconds.
  2. Check condition is when TP sensor voltage is 2 volts or less and engine speed is less than 2000 RPM. Judgement criteria is when VAF sensor output frequency is 800 Hz or more for 2 seconds.

Trouble Shooting Hints

The most likely causes for this code to be set are

  1. Air Leak Between VAF Sensor & Throttle Body
  2. Open Or Short In VAF Sensor Circuit Or Loose Connector
  3. VAF Sensor Failed
  4. ECM/PCM Failed

Diagnosis

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 12: VOLUME AIR FLOW SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). The standard value during idle should be 10 Hz or more. When the engine is revved, the frequency should increase according to the increase in engine speed. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition switch to ON position. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 7 by backprobing. Voltage should be 6-9 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If volage is as specified, turn ignition switch to LOCK position, then go to step 5 .
  3. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52. Check VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  4. Check for short to ground in circuit between VAF sensor harness connector B-14 terminal No. 7 and ECM harness connector C-51 terminal No. 19 or PCM harness connector C-52 terminal No. 19. If problem does not exist, replace VAF sensor, then go to step 9 . If problem exists, repair it, then go to step 9 .
  5. Reconnect VAF and ECM/PCM harness connectors. Start the engine and run at idle. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 7 by backprobing. When the engine is idling, voltage should be one volt or less. When the engine speed is 3000 RPM, voltage should be 6-9 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 8 .
  6. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52. Check VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  7. Check for open or harness damage in circuit between VAF sensor harness connector B-14 terminal No. 7 and ECM harness connector C-51 terminal No. 19 or PCM harness connector C-52 terminal No. 19. If problem does not exist, replace ECM/PCM, then go to step 9 . If problem exists, repair it, then go to step 9 .
  8. Ensure ignition switch is in LOCK position. Replace VAF sensor. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0101 is output, replace ECM/PCM, then go to next step. If DTC P0101 is not output, this diagnosis is complete.
  9. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0101 is output, repeat diagnostic procedure. If DTC P0101 is not output, this diagnosis is complete.

Check condition is when engine speed is more than 500 RPM. Judgement criteria is when VAF sensor output frequency is 3.3 Hz or less for 2 seconds.

The most likely causes for this code to be set are

  1. Air Leak Between VAF Sensor & Throttle Body
  2. Open Or Short In VAF Sensor Circuit Or Loose Connector
  3. VAF Sensor Failed
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 12: VOLUME AIR FLOW SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). The standard value during idling should be 10 Hz or more. When the engine is revved, the frequency should increase according to the increase in engine speed. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition switch to ON position. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 4 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 5 .
  3. Disconnect VAF sensor harness connector B14. Turn ignition switch to ON position. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 4. Battery voltage should exist. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short to ground in circuit between VAF sensor harness connector B-14 terminal No. 4 and MFI relay, then go to step 13 .
  4. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 13 . If problem does not exist, check for damage to wiring harness between MFI relay harness connector A-18X terminal No. 4 and VAF sensor harness connector B-14 terminal No. 4. If problem exists, repair it, then go to step 13 . If problem does not exist, replace VAF sensor, then go to step 13 .
  5. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  6. Turn ignition switch to ON position. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 9 .
  7. Turn ignition switch to LOCK position. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-50 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  8. Check for short to ground in circuit between VAF sensor harness connector B-14 terminal No. 3 and ECM harness connector C-58 terminal No. 61 or PCM harness connector C-55 terminal No. 65. If a problem does not exist, replace ECM/PCM, then go to step 13 . If problem exists, repair it, then go to step 13 .
  9. Turn ignition switch to LOCK position. Check for resistance between ground and VAF sensor harness connector B-14 terminal No. 5. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 12 .
  10. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  11. Check for open or harness damage in circuit between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-51 terminal No. 34 or PCM harness connector C-52 terminal No. 16. If problem does not exist, replace ECM/PCM, then go to step 13 . If problem exists, repair it, then go to step 13 .
  12. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem exists, repair it, then go to next step. If problem does not exist, replace VAF sensor, then go to next step.
  13. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0102 is output, repeat diagnostic procedure. If DTC P0102 is not output, inspection procedure is complete.

Check condition is when barometric pressure is less than 11 psi (76 kPa). Judgement criteria is when during 15 drive cycles, the changes in the sensor output voltage should be 0.015 volt, equivalent to 0.06 psi (0.4 kPa) or less. Ensure that the engine coolant is at 162°F (72°C) or higher during each of the 15 drive cycles. Also, during each of the 15 drive cycles, ensure that after the engine has been started, the engine coolant temperature has increased 73°F (23°C) or more.

The most likely causes for this code to be set are

  1. Open Or Short In BARO Pressure Sensor Circuit Or Loose Connector
  2. BARO Pressure Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, read DTCs. If DTC P0107 is not output, turn ignition switch to LOCK position, then go to next step. If DTC P0107 is output, turn ignition switch to LOCK position, then go to «DTC P0107: BAROMETRIC PRESSURE CIRCUIT LOW INPUT»(ref-135484-S11572049882002022200000) .
  2. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  3. Check for resistance between ground and VAF sensor harness connector B-14 terminal No. 5. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 6 .
  4. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  5. Check for open or harness damage in circuit between VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52. If problem does not exist, replace ECM/PCM, then go to step 9 . If problem exists, repair it, then go to step 9 .
  6. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  7. Check for open or harness damage in circuit between VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  8. Ensure ignition switch is in LOCK position. Replace VAF sensor. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0106 is output, replace ECM/PCM, then go to next step. If DTC P0106 is not output, this diagnosis is complete.
  9. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0106 is output, repeat diagnostic procedure. If DTC P0106 is not output, inspection procedure is complete.

Check condition is when two seconds or more have passed since the starting sequence was completed. Battery voltage is more than 8 volts. Judgement criteria is when BARO pressure sensor output has continued to be 7.1 psi (49 kPa) or less at approximately 15,000 ft. above sea level for 10 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In BARO Pressure Sensor Circuit Or Loose Connector
  2. BARO Pressure Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. Compare against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If scan tool value is not within specification, go to next step. If scan tool value is within specification, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM. BAROMETRIC PRESSURE SENSOR SPECIFICATIONS Altitude - Ft. (m) psi (kPa) 0 (0) 14.7 (101) 1969 (600) 13.8 (95) 3937 (1200) 12.7 (88) 5906 (1800) 11.8 (81)
  2. Turn ignition switch to ON position. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 7 by backprobing. Compare voltage against specification. See «BAROMETRIC PRESSURE SENSOR VOLTAGE»(ref-135484-S25133637712002022200000) table. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7 . BAROMETRIC PRESSURE SENSOR VOLTAGE Altitude - Ft. (m) Volts 0 (0) 3.7-4.3 1969 (600) 3.4-4.0 3937 (1200) 3.2-3.8 5906 (1800) 2.9-3.5
  3. Measure voltage between ground and ECM harness connector C-58 terminal No. 51 or PCM harness connector C-55 terminal No. 55 by backprobing. Compare voltage against specification. See «BAROMETRIC PRESSURE SENSOR VOLTAGE»(ref-135484-S25133637712002022200000) table. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 6 .
  4. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55. Check VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 18 .
  5. Reconnect any disconnect harness connectors. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. Compare against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If scan tool value is not within specification, replace ECM/PCM, then go to step 18 . If scan tool value is within specification, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  6. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55. Check VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 18 . If problem does not exist, repair open in circuit between VAF sensor Harness connector B-14 terminal No. 2 and ECM harness connector C-58 terminal No. 51 or PCM harness connector C-55 terminal No. 55, then go to step 18 .
  7. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 1 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 12 .
  8. Measure voltage between ground and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 10 .
  9. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55. Check VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, repair open in circuit between VAF sensor harness connector B-14 terminal No. 1 and ECM harness connector C-58 terminal No. 42 or PCM harness connector terminal No. 46, then go to step 18 . If problem exists, repair it, then go to step 18 .
  10. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55. Check VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 18 .
  11. Check for short to ground in circuit between VAF sensor harness connector B-14 terminal No. 1 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, replace ECM/PCM, then go to step 18 . If problem exists, repair it, then go to step 18 .
  12. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 5 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 15 .
  13. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52. Check VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 18 .
  14. Check for harness damage between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-51 terminal No. 34 or PCM harness connector C-52 terminal No. 16. If problem does not exist, replace ECM/PCM, then go to step 18 . If problem exists, repair it, then go to step 18 .
  15. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 18 .
  16. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 18 .
  17. Check for short to ground in circuit between VAF sensor harness connector B-14 terminal No. 2 and ECM harness connector C-58 terminal No. 51 or PCM harness connector C-55 terminal No. 55. If problem exists, repair it, then go to next step. If problem does not exist, replace VAF sensor, then go to next step.
  18. Ensure the ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0107 is output, repeat diagnostic procedure. If DTC P0107 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Battery voltage is more than 8 volts. Judgement criteria is when BARO pressure sensor output has continued to be 16 psi (113 kPa) or more at approximately 4000 ft. below sea level for 10 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In BARO Circuit Or Loose Connector
  2. BARO Pressure Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. Compare against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If scan tool value is not within specification, go to next step. If scan tool value is within specification, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 7 by backprobing. Compare voltage against specification. See «BAROMETRIC PRESSURE SENSOR VOLTAGE»(ref-135484-S25133637712002022200000) table. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, go to step 5 .
  3. Disconnect VAF sensor connector B-14 and ECM harness connector C-58 or PCM harness connector C-55. Check VAF sensor harness connector B-14 and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  4. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. Compare against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If scan tool value is not within specification, replace ECM/PCM, then go to step 12 . If scan tool value is within specification, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  5. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 1 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, go to step 7 .
  6. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  7. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 5 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 10 .
  8. Disconnect VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52. Check VAF sensor harness connector B-14 and ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  9. Check for open in circuit between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-51 terminal No. 34 or PCM harness connector C-52 terminal No. 16. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  10. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  11. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem exists, repair it, then go to next step. If problem does not exist, replace VAF sensor, then go to next step.
  12. Ensure the ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0108 is output, repeat diagnostic procedure. If DTC P0108 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature is more than 169°F (76°C). Check conditions must repeat 5 or more times in order; drive 1, stop 2. Drive 1 is when vehicle speed is more than 31 mph lasting a total of more than 60 seconds. Stop 2 is when vehicle speed is less than 0.9 mph lasting more than 30 seconds. Judgement criteria is when change in the intake air temperature is less than 34°F (1°C).

The most likely causes for this code to be set are

  1. Open Or Short In IAT Sensor Circuit Or Loose Connector
  2. IAT Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

CAUTIONDO NOT allow IAT sensor temperature to increase over 176°F (80°C).

Scheme 41

Scheme 41
Scheme 41
  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Remove the air intake hose from the Volume Airflow (VAF) sensor. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. Heat the IAT sensor using a hair drier. (Scheme 41) The IAT sensor temperature indicated on the scan tool should increase. If sensor is not operating properly, turn ignition switch to LOCK position, attach the air intake hose, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect the VAF sensor harness connector B-14. Measure resistance between VAF sensor connector terminals No. 5 and 6 (component side). Compare resistance with expected value. See «INTAKE AIR TEMPERATURE SENSOR RESISTANCE»(ref-135484-S00826499312002022200000) table. Heat IAT sensor with hair dryer. Resistance should decrease as IAT sensor temperature increases. Compare resistance values with expected values. If resistance values are as specified, go to next step. If resistance values are not as specified, replace VAF sensor, then go to step 9. INTAKE AIR TEMPERATURE SENSOR RESISTANCE Temperature - °F (°C) k/ohms 32 (0) 5.3-6.7 68 (20) 2.3-3.0 104 (40) 1.0-1.5 140 (60).56-.76 176 (80).30-.42
  3. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9.
  4. Measure resistance between ground and VAF sensor harness connector B-14 terminal No. 5. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 7.
  5. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9.
  6. Check for open or harness damage in circuit between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-51 terminal No. 34 or PCM harness connector C-52 terminal No. 16. If problem does not exist, replace ECM/PCM, then go to step 9. If problem exists, repair it, then go to step 9.
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9.
  8. Check for open or harness damage in circuit between VAF sensor harness connector B-14 terminal No. 6 and ECM harness connector C-58 terminal No. 62 or PCM harness connector C-55 terminal No. 62. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  9. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0111 is output, repeat diagnostic procedure. If DTC P0111 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Judgement criteria is when IAT sensor output voltage has continued to be 0.2 volt or less at 239°F (115°C) or more for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In IAT Sensor Circuit Or Loose Connector
  2. IAT Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. The intake air temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  3. Measure resistance between VAF sensor connector terminals No. 5 and 6 (component side). Resistance should be 0.3-1.0 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace VAF sensor, then go to step 6 .
  4. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check for short to ground in circuit between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-51 terminal No. 36 or PCM harness connector C-52 terminal No. 16. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  5. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  6. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0112 is output, repeat diagnostic procedure. If DTC P0112 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Judgement criteria is when IAT sensor output voltage has continued to be 4.5 volts or more at -40°F (-40°C) or less for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In IAT Sensor Circuit Or Loose Connector
  2. IAT Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. The intake air temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect VAF sensor harness connector B-14. Check VAF sensor harness connector B-14 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  3. Measure resistance between VAF sensor connector terminals No. 5 and 6 (component side). Resistance should be 0.3-1.0 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace VAF sensor, then go to step 11 .
  4. Turn ignition switch to ON position. Measure voltage between ground and VAF sensor harness connector B-14 terminal No. 6. Voltage should be 4.5-4.9 volts. If voltage is not as specified, go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 8 .
  5. Measure voltage between ground and ECM harness connector C-58 terminal No. 62 or PCM harness connector C-55 terminal No. 64. Voltage should be 4.5-4.9 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 7 .
  6. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 11 . If problem does not exist, repair open in circuit between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-58 terminal No. 62 or PCM harness connector C-55 terminal No. 64, then go to step 11 .
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to step 11 . If problem exists, repair it, then go to step 11 .
  8. Measure resistance between ground and VAF sensor harness connector B-14 terminal No. 5. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, replace ECM/PCM, then go to step 11 .
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  10. Check for open in circuit between VAF sensor harness connector B-14 terminal No. 5 and ECM harness connector C-51 terminal No. 34 or PCM harness connector C-52 terminal No. 16. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0113 is output, repeat diagnostic procedure. If DTC P0113 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature was 45°F (7°C) or more immediately before the engine was stopped at the last drive, or engine coolant temperature was 45°F (7°C) or more when the engine started. Only one monitor during one drive cycle. Judgement criteria is when engine coolant temperature fluctuates within 34°F (1°C) after 5 minutes have passed since the engine was started. However, time is not counted if any of the following conditions are met: intake air temperature is 140°F (60°C) or more, Volume Airflow (VAF) sensor output frequency is 70 Hz or less or during fuel shut-off operation.

The most likely causes for this code to be set are

  1. Open Or Short In Ect Sensor Circuit Or Loose Connector
  2. ECT Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition switch to ON position. Measure voltage between ground and ECT sensor harness connector B-11 terminal No. 1 by backprobing. Compare voltage against specification. See «ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE»(ref-135484-S20207583782002022200000) table. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 5 . ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE Temperature - °F (°C) Volts 32 (0) 3.2-3.8 68 (20) 2.3-2.9 104 (40) 1.3-1.9 140 (60) 0.7-1.3 176 (80) 0.3-0.9
  3. Disconnect ECT sensor harness connector B-11. Check ECT sensor harness connector B-11 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  4. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, replace ECM/PCM, then go to step 14 . If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  5. Disconnect ECT sensor harness connector B-11. Check ECT sensor harness connector B-11 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  6. Turn ignition switch to ON position. Measure voltage between ground and ECT sensor harness connector B-11 terminal No. 1. Voltage should be 4.5-4.9 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 8 .
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  8. Check resistance between ground and ECT sensor harness connector B-11 terminal No. 2. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 11 .
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  10. Check for harness damage between ECT sensor harness connector B-11 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  11. Remove ECT sensor. With the temperature sensing portion of ECT sensor immersed in hot water, check resistance across ECT sensor terminals (component side). See «ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE»(ref-135484-S05976815582002022200000) table. If resistance is as specified, reinstall ECT sensor, then go to next step. If resistance is not as specified, replace ECT sensor, then go to step 14 . ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE Temperature - °F (°C) k/Ohms -4 (-20) 14-17 32 (0) 5.1 -6.5 68 (20) 2.1 -2.7 104 (40) 0.9 - 1.3 140 (60) 0.48 -0.68 176 (80) 0.26 -0.36
  12. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  13. Check for harness damage between ECT sensor harness connector B-11 terminal No. 1 and ECM harness connector C-58 terminal No. 44 or PCM harness connector C-55 terminal No. 44. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0116 is output, repeat diagnostic procedure. If DTC P0116 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Judgement criteria is when engine coolant temperature has continued to be 0.1 volt or less, which corresponds to an engine coolant temperature of 284°F (140°C) or more for 2 seconds.

The most likely causes for this code to be set are

  1. ECT Sensor Failed
  2. Open Or Short In ECT Sensor Circuit Or Loose Connector
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect ECT sensor harness connector B-11. Check ECT sensor harness connector B-11 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  3. Check for short to ground in circuit between ECT sensor harness B-11 connector terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  4. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  5. Remove ECT sensor. With the temperature sensing portion of ECT sensor immersed in hot water, check resistance across ECT sensor terminals (component side). See «ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE»(ref-135484-S05976815582002022200000) table. If resistance is as specified, reinstall ECT sensor, replace ECM/PCM, then go to next step. If resistance is not as specified, replace ECT sensor, then go to next step.
  6. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0117 is output, repeat diagnostic procedure. If DTC P0117 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Judgement criteria is when engine coolant temperature has continued to be 4.6 volts or more, which corresponds to an engine coolant temperature of -49°F (-45°C) or less for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In ECT Sensor Circuit Or Loose Connector
  2. ECT Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect ECT sensor harness connector B-11. Check ECT sensor connector B-11 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  3. Turn ignition switch to ON position. Measure voltage between ground and ECT sensor harness connector B-11 terminal No. 1. Voltage should be 4.5-4.9 volts. If voltage is not as specified, go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 7 .
  4. Measure voltage between ECM harness connector C-58 terminal No. 44 or PCM harness connector C-55 terminal No. 44. Voltage should be 4.5-4.9 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 6 .
  5. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 11 . If problem does not exist, repair open in circuit between ECT sensor harness connector B-11 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57, then go to step 11 .
  6. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to step 11 . If problem exists, repair it, then go to step 11 .
  7. Measure resistance between ground and ECT sensor harness connector B-11 terminal No. 2. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 10 .
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  9. Check for open in circuit between ECT sensor harness connector B-11 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 11 . If problem exists, repair it, then go to step 11
  10. Remove ECT sensor. With the temperature sensing portion of ECT sensor immersed in hot water, check resistance across ECT sensor terminals (component side). See «ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE»(ref-135484-S05976815582002022200000) table. If resistance is as specified, reinstall ECT sensor, replace ECM/PCM, then go to next step. If resistance is not as specified, replace ECT sensor, then go to next step.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0118 is output, repeat diagnostic procedure. If DTC P0118 is not output, this diagnosis is complete.
  1. Check condition is when 2 seconds or more have passed since the starting sequence was completed, engine speed is more than 2000 RPM and volumetric efficiency is more than 60 percent. Judgement criteria is when TP sensor output voltage has continued to be 0.8 volt or less for 2 seconds.
  2. Check condition is when 2 seconds or more have passed since the starting sequence was completed, engine speed is less than 3000 RPM and volumetric efficiency is less than 30 percent. Judgement criteria is when TP sensor output voltage continued to be 4.6 volts or more for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In TP Sensor Circuit Or Loose Connector
  2. TP Sensor Failed Or Misadjusted
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 14: THROTTLE POSITION SENSOR. With throttle valve in idle position, voltage should be 0.535-0.735 volt. With throttle valve in fully open position, voltage should be 4.5-5.5 volts. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Knock Sensor Disconnect TP sensor harness connector B-07. Check TP sensor harness connector B-07 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  3. Measure resistance between TP sensor connector (component side) terminals No. 1 and 3, then between terminals No. 1 and 4. Resistance should be 3.5-6.5 k/ohms. Measure resistance between TP sensor connector (component side) terminals No. 1 and 3 while slowly opening throttle valve from idle position to fully open position. Resistance should change smoothly in proportion to opening of valve. If resistance is as specified, go to next step. If resistance is not as specified, replace TP sensor, then go to step 14 .
  4. Turn ignition switch to ON position. Measure voltage between ground and TP sensor harness connector B-07 terminal No. 4. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 7 .
  5. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  6. Check for harness damage between TP sensor harness connector B-07 terminal No. 4 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  7. Check for resistance between ground and TP sensor harness connector terminal No. 1. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 10 .
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  9. Check for harness damage or open in circuit between TP sensor harness connector B-07 terminal No. 1 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  10. Disconnect ECM harness connectors C-58 and 62 or PCM harness connectors C-55 and C-59. Check ECM harness connectors C-58 and C-62 or PCM harness connectors C-55 and C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  11. Check for harness damage between TP sensor harness connector B-07 terminal No. 3 and ECM harness connector C-62 terminal No. 78 or PCM harness connector C-59 terminal No. 78. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  12. Check the TP sensor adjustment. See THROTTLE POSITION SENSOR under ADJUSTMENTS in SYSTEM & COMPONENT TESTING article. If the output voltage is as specified, go to next step. If the output voltage is not as specified, adjust it. Then go to step 14 .
  13. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 14: THROTTLE POSITION SENSOR. With throttle valve in idle position, voltage should be 0.535-0.735 volt. With throttle valve in fully open position, voltage should be 4.5-5.5 volts. If voltage is not as specified, turn ignition switch to LOCK position, replace ECM/PCM, then go to next step. If voltage is as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0121 is output, repeat diagnostic procedure. If DTC P0121 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Judgement criteria is when TP sensor output voltage has continued to be 0.2 volt or less for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In TP Sensor Circuit Or Loose Connector
  2. TP Sensor Failed Or Misadjusted
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 14: THROTTLE POSITION SENSOR. With throttle valve in idle position, voltage should be 0.535-0.735 volt. With throttle valve in fully open position, voltage should be 4.5-5.5 volts. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect TP sensor harness connector B-07. Check TP sensor harness connector B-07 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  3. Turn ignition switch to ON position. Measure voltage between ground and TP sensor harness connector B-07 terminal No. 1. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 6 .
  4. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  5. Check for open or short to ground in circuit between TP sensor harness connector B-07 terminal No. 4 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, replace ECM/PCM, then go to step 11 . If problem exists, repair it, then go to step 11 .
  6. Measure resistance between TP sensor connector (component side) terminals No. 1 and 3, then between terminals No. 1 and 4. Resistance should be 3.5-6.5 k/ohms. Measure resistance between TP sensor connector (component side) terminals No. 1 and 3 while slowly opening throttle valve from idle position to fully open position. Resistance should change smoothly in proportion to opening of valve. If resistance is as specified, go to next step. If resistance is not as specified, replace TP sensor, then go to step 11 .
  7. Check ECM harness connectors C-58 and C-62 or PCM harness connectors C-55 and C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  8. Check for open or short to ground in circuit between TP sensor harness connector B-07 terminal No. 3 and ECM harness connector C-62 terminal No. 78 or PCM harness connector C-59 terminal No. 78. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  9. Check for short to ground in circuit between TP sensor harness connector B-07 terminal No. 3 and auto-cruise control-ECU harness connector C-20 terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  10. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 14: THROTTLE POSITION SENSOR. With throttle valve in idle position, voltage should be 0.535-0.735 volt. With throttle valve in fully open position, voltage should be 4.5-5.5 volts. If voltage is not as specified, turn ignition switch to LOCK position, replace ECM/PCM, then go to next step. If voltage is as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0122 is output, repeat diagnostic procedure. If DTC P0122 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed. Engine speed is less than 1000 RPM. Volumetric efficiency is less than 60 percent. Judgement criteria is when TP sensor output voltage has continued to be 2 volts or more for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In TP Sensor Circuit Or Loose Connector
  2. TP Sensor Failed Or Misadjusted
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 14: THROTTLE POSITION SENSOR. With throttle valve in idle position, voltage should be 0.535-0.735 volt. With throttle valve in fully open position, voltage should be 4.5-5.5 volts. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect TP sensor harness connector B-07. Check TP sensor harness connector B-07 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 8 .
  3. Measure resistance between ground and TP sensor harness connector B-07 terminal No. 1. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 6 .
  4. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals If problem does not exist, go to next step. If problem exists, repair it, then go to step 8 .
  5. Check for open or harness damage in circuit between TP sensor harness connector B-07 terminal No. 1 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 8 . If problem exists, repair it, then go to step 8 .
  6. Measure resistance between TP sensor connector terminals No. 1 and 4 (component side). Resistance should be 3.5-6.5 k/ohms. Measure resistance between TP sensor connector terminals No. 1 and 3 (component side) while slowly opening throttle valve from idle position to fully open position. Resistance should change smoothly in proportion to opening of valve. If resistance is as specified, go to next step. If resistance is not as specified, replace TP sensor, then go to step 8 .
  7. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 14: THROTTLE POSITION SENSOR. With throttle valve in idle position, voltage should be 0.535-0.735 volt. With throttle valve in fully open position, voltage should be 4.5-5.5 volts. If sensor is not operating properly, turn ignition switch to LOCK position, replace ECM/PCM, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  8. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0123 is output, repeat diagnostic procedure. If DTC P0123 is not output, this diagnosis is complete.

Check condition is when coolant temperature decreases from more than 104°F (40°C) to less than 104°F (40°C). Then the engine coolant temperature has continued to be 104°F (40°C) or less for 5 minutes. Judgement criteria is when about 60-300 seconds have passed for the engine coolant temperature to rise about 158°F (70°C) after starting sequence was completed. However, time is not counted when fuel is shut off.

The most likely causes for this code to be set are

  1. Open Or Short In ECT Sensor Circuit Or Loose Connector
  2. ECT Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition switch to ON position. Measure voltage between ground and ECT sensor harness connector B-11 terminal No. 1 by backprobing. Compare voltage to expected value. See «ECT SENSOR VOLTAGE»(ref-135484-S38805347632002121600000) table. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 5 . ECT SENSOR VOLTAGE Temperature - °F (°C) Volts -4 (-20) 3.9-4.5 32 (0) 3.2-3.8 68 (20) 2.3-2.9 104 (40) 1.3-1.9 140 (80) 0.7-1.3 176 (80) 0.3-0.9
  3. Disconnect ECT sensor harness connector B-11. Check ECT sensor harness connector B-11 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  4. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is not operating properly, turn ignition switch to LOCK position, replace ECM/PCM, then go to step 14 . If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  5. Disconnect ECT sensor harness connector B-11. Check ECT sensor harness connector B-11 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  6. Turn ignition switch to ON position. Check voltage between ground and ECT sensor harness connector B-11 terminal No. 1. Voltage should be 4.5-4.9 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 8 .
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  8. Measure resistance between ground and ECT sensor harness connector B-11 terminal No. 2. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 11 .
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  10. Check for harness damage between ECT sensor harness connector B-11 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  11. Remove ECT sensor. With the temperature sensing portion of ECT sensor immersed in hot water, check resistance across ECT sensor terminals (component side). See «ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE»(ref-135484-S05976815582002022200000) table. If resistance is as specified, reinstall ECT sensor, then go to next step. If resistance is not as specified, replace ECT sensor, then go to step 14 .
  12. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  13. Check for harness damage between ECT sensor harness connector B-11 terminal No. 1 and ECM harness connector C-58 terminal No. 44 or PCM harness connector C-55 terminal No. 44. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0125 is output, repeat diagnostic procedure. If DTC P0125 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature is 14-171°F (-10-77°C) when engine is started. Engine coolant temperature minus intake air temperature is 41°F (5°C) or less when engine is started. Intake air temperature when engine is started minus intake air temperature is 41°F (5°C) or less. Volume Airflow (VAF) sensor output frequency is 50-100 Hz or less for 300 seconds or less. Judgement criteria is when the time for the engine coolant temperature to rise to 171°F (77°C) takes longer than approximately 14 to 21 minutes.

The most likely causes for this code to be set are

  1. Faulty Thermostat
  2. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

Check the thermostat and cooling system. If problem does not exist, replace the ECM/PCM, then check that the DTC P0128 does not reset. If problem exists, repair it, then check that the DTC P0128 does not reset.

Check condition is when 3 minutes or more have passed since the starting sequence was completed, HO2S 1/1 signal voltage has continued to be 0.2 volt or less, engine coolant temperature is more than 169°F (76°C), engine speed is more than 1200 RPM and volumetric efficiency is more than 25 percent. Monitoring time is 7 seconds. Judgement criteria is when input voltage supplied to the ECM/PCM interface circuit is more than 4.5 volts when 5 volts is applied to the HO2S 1/1 output line through a resistor. Only one monitor is performed during one drive cycle.

The most likely causes for this code to be set are

  1. HO2S 1/1 Deteriorated
  2. Open In HO2S 1/1 Output Circuit
  3. Open In HO2S 1/1 Ground Circuit
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 39: HEATED OXYGEN SENSOR BANK 1, SENSOR 1. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 1/1 output voltage should read 0.6-1.0 volt. When the engine is idling, the output voltage should alternate between 0.4 volt or less and 0.6-1.0 volt. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Start the engine and run at idle. Measure voltage between ground and HO2S 1/1 harness connector B-27 terminal No. 4 by backprobing. With engine speed at 2500 RPM, HO2S 1/1 voltage should alternate between zero volts and 0.8 volt. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 7.
  3. Start the engine and run at idle. Measure voltage between ground and ECM harness connector C-62 terminal No. 72 or PCM harness connector C-59 terminal No. 72 by backprobing. With engine warm and engine speed at 2500 RPM, HO2S 1/1 voltage should alternate between zero volts and 0.8 volt. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 6.
  4. Disconnect HO2S 1/1 harness connector B-27 and ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 1/1 harness connector B-27 and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  5. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 39: HEATED OXYGEN SENSOR BANK 1, SENSOR 1. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 1/1 output voltage should read 0.6-1.0 volt. When engine is idling, voltage should alternate between less than 0.4 volt and more than 0.6 volt. If scan tool readings are not as specified, replace ECM/PCM, then go to step 15. If scan tool readings are as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  6. Disconnect HO2S 1/1 harness connector B-27 and ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 1/1 harness connector B-27 and ECM harness connector C-62 terminal or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 15. If problem does not exist, repair open or harness damage in circuit between HO2S 1/1 harness connector B-27 terminal No. 4 and ECM harness connector C-62 terminal No. 72 or PCM harness connector C-59 terminal No. 72, then go to step 15.
  7. Disconnect HO2S 1/1 harness connector B-27. Check HO2S 1/1 harness connector B-27 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  8. Check for resistance between ground and HO2S 1/1 harness connector B-27 terminal No. 2. Resistance should be less than 2 ohms. If resistance not as specified, go to next step. If is as specified, go to step 11.
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  10. Check for open or harness damage in circuit between HO2S 1/1 harness connector B-27 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem exists, repair it, then go to step 15. If problem does not exist, replace ECM/PCM, then go to step 15.
  11. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  12. Check for open or harness damage in circuit between HO2S 1/1 harness connector B-27 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  13. Check for damage or short to ground in circuit between HO2S 1/1 harness connector B-27 terminal No. 4 and ECM harness connector C-62 terminal No. 72 or PCM harness connector C-59 terminal No. 72. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  14. Connect test harness to the connector on the HO2S 1/1 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 1/1 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, turn ignition switch to LOCK position, replace the ECM/PCM, then go to next step. If the voltage is not as specified, replace the HO2S 1/1, then go to next step.
  15. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor and other monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135484-S15606817862002022200000) and «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0132 is output, repeat diagnostic procedure. If DTC P0132 is not output, this diagnosis is complete.

Scheme 42

Scheme 42
Scheme 42

Check condition is when engine coolant temperature is more than 122°F (50°C). Engine speed is 1250-3000 RPM. Volumetric efficiency is 20-60 percent. Engine is under closed loop air/fuel control and throttle is open. Short-term trim is more than -30, but less than 25 percent. More than 3 seconds have elapsed after the above mentioned conditions have been met. Monitoring time is 12 seconds by 7 times. Judgement criteria is when the HO2S 1/1 lean/rich signals alternate 11 times or less for 12 seconds.

The most likely causes for this code to be set are

  1. HO2S 1/1 Deteriorated
  2. ECM/PCM Failed

If sensor switch time is longer than the judgement criteria due to the scan tool OBD-II test MODE - HO2S TEST RESULTS, it is assumed that the HO2S 1/1 has deteriorated. If it is short, it is assumed that the harness is damaged or has a short circuit. If the HO2S signal voltage has not changed even once (lean/rich) after the DTC was erased, the sensor switch time will display as "0" seconds.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 39: HEATED OXYGEN SENSOR BANK 1, SENSOR 1. Warm engine to normal operating temperature. When engine is held at 2500 RPM, HO2S 1/1 output voltage should alternate between 0.4 volt or less and 0.6-1.0 volt 10 times or more within 10 seconds. If scan tool readings are not as specified, turn ignition switch to LOCK position, replace HO2S 1/1, then go to next step. If scan tool readings are as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0133 is output, repeat diagnostic procedure. If DTC P0133 is not output, this diagnosis is complete.

Check condition is when 30 seconds or more have passed since the starting sequence was completed. Engine coolant temperature is more than 169°F (76°C). Engine speed is more than 1200 RPM. Volumetric efficiency is more than 30 percent. Throttle position sensor voltage is less than 4 volts. DTC set conditions are not monitored when fuel is being shut off. Monitor runs for 30 seconds. Judgement criteria is when HO2S 1/1 voltage does not get across 0.5 volt within about 30 seconds.

The most likely causes for this code to be set are

  1. HO2S 1/1 deteriorated.
  2. Open Circuit In HO2S 1/1 Output Line
  3. Open Circuit In HO2S 1/1 Ground Line
  4. ECM/PCM Failed

When the HO2S 1/1 begins to deteriorate, the HO2S 1/1 output voltage will deviate from the voltage when the sensor was new (normally 0.5 volt at stoichiometric ratio). This deviation will be corrected by the HO2S 1/2. If the HO2S 1/2 responds poorly because it has deteriorated, it will improperly correct the HO2S 1/1. Thus, even when closed loop control is being effected, the fluctuation of the HO2S 1/1 output voltage decreases, without intersecting with 0.5 volt. As a result, there is a possibility of DTC P0134 being stored in memory.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 69: HEATED OXYGEN SENSOR BANK 1, SENSOR 2. Warm engine to normal operating temperature. When engine is revved, HO2S 1/2 output voltage should read 0.6-1.0 volt. When the engine is idling, the output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, refer to «DTC P0137: HEATED OXYGEN SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)»(ref-135484-S33716135282002022200000), «DTC P0138: HEATED OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)»(ref-135484-S37260766902002120400000) and «DTC P0139: HEATED OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2)»(ref-135484-S05214200322002022200000).
  2. Check for exhaust leaks. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  3. Check intake system for vacuum leaks. If problem does not exist, turn ignition switch to LOCK position, then go to next step. If problem exists, repair it, then go to step 14.
  4. Disconnect HO2S 1/1 harness connector B-27. Check HO2S 1/1 harness connector B-27 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  5. Connect test harness to the connector on the HO2S 1/1 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 1/1 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, turn ignition switch to LOCK position, then go to next step. If the voltage is not as specified, turn ignition switch to LOCK position, replace the HO2S 1/1, then go to step 14.
  6. Disconnect intermediate connector B-48. Check intermediate connector B-48 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  7. Measure resistance of fuel injector No. 1 circuit between intermediate connector B-48 terminals No. 1 and 2. Measure resistance of fuel injector No. 3 circuit between intermediate connector B-48 terminals No. 1 and 3. Measure resistance of fuel injector No. 5 circuit between intermediate connector B-48 terminals No. 1 and 4. Resistance of each circuit should be 13-16 ohms at 68°F (20°C). If any resistance is not as specified, go to next step. If all resistances are as specified, go to step 10.
  8. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Check suspect fuel injector harness connector for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  9. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, repair harness damage in circuit between fuel injector and intermediate connector B-48, then go to step 14. If resistance is not as specified, replace fuel injector, then go to step 14.
  10. Disconnect ECM harness connectors C-51 and C-62 or PCM connectors C-52 and C-59. Check ECM harness connectors C-51 and C-62 or PCM harness connectors C-52 and C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  11. Check for harness damage between HO2S 1/1 harness connector B-27 terminal No. 4 and ECM harness connector C-62 terminal No. 72 or PCM harness connector C-59 terminal No. 72. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  12. Check for harness damage between intermediate connector B-48 terminal No. 2 (cylinder No. 1) and ECM harness connector C-51 terminal No. 1 or PCM harness connector C-52 terminal No. 1. Check for harness damage between intermediate connector B-48 terminal No. 3 (cylinder No. 3) and ECM harness connector C-51 terminal No. 24 or PCM harness connector C-52 terminal No. 24. Check for harness damage between intermediate connector B-48 terminal No. 4 (cylinder No. 5) and ECM harness connector C-51 terminal No. 10 or PCM harness connector C-52 terminal No. 10. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14.
  13. Check fuel pressure. See «FUEL SYSTEM»(ref-135483-S30633135832002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Fuel pressure should be 39 psi (270 kPa) at idle with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) at idle with fuel pressure regulator vacuum line disconnected. If fuel pressure is normal, replace ECM/PCM, then go to next step. If fuel pressure is not normal, repair it, then go to next step.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0134 is output, repeat diagnostic procedure. If DTC P0134 is not output, this diagnosis is complete.

Check condition is when 60 seconds have elapsed since the start of the previous monitoring. Engine coolant temperature is more than 68°F (20°C). While HO2S 1/1 heater is on. Battery voltage is 11-16 volts. Judgement criteria is when HO2S 1/1 heater current has continued to be less than 0.16 amp or more than 7.5 amps, for 4 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In HO2S 1/1 Heater Circuit
  2. Open Circuit In HO2S 1/1 Heater
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Disconnect HO2S 1/1 harness connector B-27. Check HO2S 1/1 harness connector B-27 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  2. Connect test harness to the connector on the HO2S 1/1 (component side). Measure resistance between HO2S 1/1 connector terminals No. 1 (Red clip) and No. 3 (Blue clip). (Scheme 42) Resistance should be 4.5-8.0 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace HO2S 1/1, then go to step 12.
  3. Turn ignition switch to ON position. Measure voltage between ground and HO2S 1/1 harness connector B-27 terminal No. 1. Battery voltage should exist. If battery voltage does not as exist, go to next step. If battery voltage exists, go to step 5.
  4. Turn ignition switch to LOCK position. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and HO2S 1/1 harness connector B-27 terminal No. 1, then go to step 12.
  5. Turn ignition switch to LOCK position. Reconnect HO2S 1/1 harness connector B-27. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 4 or PCM harness connector C-52 terminal No. 4 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 8.
  6. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  7. Check for open or short to ground in circuit between HO2S 1/1 harness connector B-27 terminal No. 3 and ECM harness connector C-51 terminal No. 4 or PCM harness connector C-52 terminal No. 4. If problem does not exist, replace ECM/PCM, then go to step 12. If problem exists, repair it, then go to step 12.
  8. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  9. Check for harness damage between MFI relay harness connector A-18X terminal No. 4 and HO2S 1/1 harness connector B-27 terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  10. Check for harness damage between HO2S 1/1 harness connector B-27 terminal No. 3 and ECM harness connector C-51 terminal No. 4 or PCM harness connector C-52 terminal No. 4. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0135 is output, replace ECM/PCM, then go to next step. If DTC P0135 is not output, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0135 is output, repeat diagnostic procedure. If DTC P0135 is not output, this diagnosis is complete.

Check condition is when 3 minutes or more have passed since the starting sequence was completed, HO2S 1/2 signal voltage has continued to be 0.15 volt or less, engine coolant temperature is more than 169°F (76°C), engine speed is more than 1200 RPM and volumetric efficiency is more 25 percent. At least 20 seconds have passed since fuel shut-off control was cancelled. The HO2S 1/1 outputs 0.5 volt or more. After the ignition switch is turned to ON position, the changes in the output voltage of the HO2S 1/2 is less than 0.078 volt. Monitoring time is 10 seconds. Judgement criteria is when making the air/fuel ratio 15 percent richer for 10 seconds does not result in raising the HO2S 1/2 output voltage to more than 0.15 volt. Only one monitor is performed during one drive cycle.

The most likely causes for this code to be set are

  1. HO2S 1/2 Failed
  2. Open Circuit In HO2S 1/2 Output Line
  3. Short Circuit In HO2S 1/2 Output Line
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 69: HEATED OXYGEN SENSOR BANK 1, SENSOR 2. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 1/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect HO2S 1/2 harness connector B-28. Connect test harness to the connector on the HO2S 1/2 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 1/2 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, turn ignition switch to LOCK position, then go to next step. If the voltage is not as specified, replace the HO2S 1/2, then go to step 5.
  3. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 1/2 harness connector B-28 and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 5.
  4. Check for short to ground in circuit between front HO2S 1/2 harness connector B-28 terminal No. 4 and ECM harness connector C-62 terminal No. 74 or PCM harness connector C-59 terminal No. 74. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  5. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0137 is output, repeat diagnostic procedure. If DTC P0137 is not output, this diagnosis is complete.

Check condition is when 3 minutes or more have passed since the starting sequence was completed, HO2S 1/2 signal voltage has continued to be 0.15 volt or less, engine coolant temperature is more than 169°F (76°C), engine speed is more than 1200 RPM and volumetric efficiency is more 25 percent. Monitoring time is 7 seconds. Judgement criteria is when input voltage supplied to the ECM/PCM interface circuit is more than 4.5 volts when 5 volts is applied to the HO2S 1/2 output line through a resistor. Only one monitor is performed during one drive cycle.

The most likely causes for this code to be set are

  1. HO2S 1/2 Failed
  2. Open Circuit In HO2S 1/2 Output Line
  3. Open Circuit In HO2S 1/2 Ground Line
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 69: HEATED OXYGEN SENSOR BANK 1, SENSOR 2. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 1/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Start the engine and run at idle. Measure voltage between ground and HO2S 1/2 harness connector B-28 terminal No. 4 by backprobing. Warm engine to normal operating temperature. When engine is revved, HO2S 1/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to step 7.
  3. Start the engine and run at idle. Measure voltage between ground and ECM harness connector C-62 terminal No. 74 or PCM harness connector C-59 terminal No. 74 by backprobing. Warm engine to normal operating temperature. When engine is held at 2500 RPM, HO2S 1/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to step 6.
  4. Disconnect HO2S 1/2 harness connector B-28. Check HO2S 1/2 harness connector B-28 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  5. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 69: HEATED OXYGEN SENSOR BANK 1, SENSOR 2. Warm engine to normal operating temperature. When engine is revved, HO2S 1/2 output voltage should alternate between about zero volts and 0.6-1.0 volt. If sensor is not operating properly, replace ECM/PCM, then go to step 15. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  6. Disconnect HO2S 1/2 harness connector B-28 and ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 1/2 harness connector B-28 and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 15. If problem does not exist, repair open or harness damage in circuit between HO2S 1/2 harness connector B-28 terminal No. 4 and ECM harness connector C-62 terminal No. 74 or PCM harness connector C-59 terminal No. 74, then go to step 15.
  7. Disconnect HO2S 1/2 harness connector B-28. Check HO2S 2/2 harness connector B-28 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  8. Measure resistance between ground and HO2S 2/2 harness connector B-28 terminal No. 2. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 11.
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  10. Check for open or harness damage in circuit between HO2S 1/2 harness connector C-28 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM then go to step 15. If problem exists, repair it, then go to step 15.
  11. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  12. Check for harness damage between HO2S 1/2 harness connector C-28 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  13. Check for short to ground or harness damage in circuit between HO2S 1/2 harness connector C-28 terminal No. 4 and ECM harness connector C-62 terminal No. 74 or PCM harness connector C-59 terminal No. 74. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  14. Disconnect HO2S 1/2 harness connector B-28. Connect test harness to the connector on the HO2S 1/2 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 1/2 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, replace ECM/PCM then go to next step. If the voltage is not as specified, replace the HO2S 1/2, then go to next step.
  15. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor and other monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135484-S15606817862002022200000) and «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0138 is output, repeat diagnostic procedure. If DTC P0138 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature is more than 169°F (76°C), the HO2S 1/1 is active and the cumulative Volume Airflow (VAF) sensor output frequency is more than 4,000 Hz under the following conditions, repeated 3 or more times: drive 1, stop 2. Drive 1 is when engine speed is more than 1500 RPM, volumetric efficiency is more than 40 percent, vehicle speed is more than 18.7 mph, a total of more than 10 seconds have elapsed with the above mentioned conditions, and more than 2 seconds have elapsed with the fuel shut off. Stop 2 is when vehicle speed must be less than 0.9 mph. Judgement criteria is when change in the output voltage of the HO2S 1/2 is less than 0.078 volt. Monitoring stops after fuel has been shut off for more than 38 seconds.

The most likely causes for this code to be set are

  1. HO2S 1/2 Failed
  2. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 69: HEATED OXYGEN SENSOR BANK 1, SENSOR 2. Warm engine to normal operating temperature. After increasing the output voltage 0.15 volt or more by revving the engine, allow engine to idle. Confirm that the output voltage reduces to 0.15 volts or less within 3 seconds. If sensor is not operating properly, turn ignition switch to LOCK position, replace the HO2S 1/2, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor pattern. See «HEATED OXYGEN SENSOR MONITOR»(ref-135484-S15606817862002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0139 is output, repeat diagnostic procedure. If DTC P0139 is not output, this diagnosis is complete.

Check condition is when 60 seconds have elapsed since the start of the previous monitoring, engine coolant temperature is more than 68°F (20°C), the HO2S 1/1 heater is on and battery positive voltage is 11-16 volts. Judgment criteria is when heater current of the HO2S 1/2 heater is less than 0.16 amp or more than 5.0 amps for 4 seconds.

The most likely causes for this code to be set are

  1. Open or short in HO2S 1/2 heater circuit.
  2. Open circuit in HO2S 1/2 heater.
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Disconnect HO2S 1/2 harness connector B-28. Check HO2S 1/2 harness connector B-28 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  2. Connect test harness to the connector on the HO2S 1/2 (component side). Measure resistance between HO2S 1/2 connector terminals No. 1 (Red clip) and No. 3 (Blue clip). (Scheme 42) Resistance should be 11-18 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace HO2S 1/2 then go to step 12.
  3. Turn ignition switch to ON position. Measure voltage between ground and HO2S 1/2 harness connector B-28 terminal No. 1. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position then go to next step. If battery voltage exists, turn ignition switch to LOCK position then go to step 5.
  4. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and HO2S 1/2 harness connector B-28 terminal No. 1, then go to step 12.
  5. Reconnect HO2S 1/2 harness connector B-28. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 27 or PCM harness connector C-52 terminal No. 27 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 8.
  6. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  7. Check for open or short to ground in circuit between HO2S 1/2 harness connector B-28 terminal No. 3 and ECM harness connector C-51 terminal No. 27 or PCM harness connector C-52 terminal No. 27. If problem does not exist, replace ECM/PCM, then go to step 12. If problem exists, repair it, then go to step 12.
  8. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  9. Check for harness damage in circuit between HO2S 1/2 harness connector B-28 terminal No. 1 and MFI relay harness connector A-18X terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  10. Check for harness damage in circuit between HO2S 1/2 harness connector B-28 terminal No. 3 and ECM harness connector C-51 terminal No. 27 or PCM harness connector C-52 terminal No. 27. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0141 is output, replace ECM/PCM, then go to next step. If DTC P0141 is not output, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0141 is output, repeat diagnostic procedure. If DTC P0141 is not output, this diagnosis is complete.

Check condition is when 3 minutes or more have passed since the starting sequence was completed, HO2S 2/1 signal voltage has continued to be 0.2 volt or less, engine coolant temperature is more than 169°F (76°C), engine speed is more than 1200 RPM and volumetric efficiency is more than 25 percent. Monitoring time is 7 seconds. Judgement criteria is when input voltage supplied to the ECM/PCM interface circuit is more than 4.5 volts when 5 volts is applied to the HO2S 2/1 output line through a resistor. Only one monitor is performed during one drive cycle.

The most likely causes for this code to be set are

  1. HO2S 2/1 Deteriorated
  2. Open in HO2S 2/1 Output Circuit
  3. Open in HO2S 2/1 Ground Circuit
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 11: HEATED OXYGEN SENSOR BANK 2, SENSOR 1. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 1/1 output voltage should read 0.6-1.0 volt. When the engine is idling, the output voltage should alternate between 0.4 volt or less and 0.6-1.0 volt. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Start the engine and run at idle. Measure voltage between ground and HO2S 2/1 harness connector B-24 terminal No. 4 by backprobing. With engine speed at 2500 RPM, HO2S 2/1 voltage should alternate between zero volts and 0.8 volt. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 7.
  3. Measure voltage between ground and ECM harness connector C-62 terminal No. 71 or PCM harness connector C-59 terminal No. 71 by backprobing. With engine warm and engine speed at 2500 RPM, HO2S 2/1 voltage should alternate between zero volts and 0.8 volt. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 6.
  4. Disconnect HO2S 2/1 harness connector B-24 and ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 2/1 harness connector B-24 and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  5. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 11: HEATED OXYGEN SENSOR BANK 2, SENSOR 1. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 2/1 output voltage should read 0.6-1.0 volt. When engine is idling, voltage should alternate between 0.4 volt and 0.6-1.0 volt. If scan tool readings are not as specified, replace ECM/PCM, then go to step 15. If scan tool readings are as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  6. Disconnect HO2S 2/1 harness connector B-24 and ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 2/1 harness connector B-24 and ECM harness connector C-62 terminal or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 15. If problem does not exist, repair open or harness damage in circuit between HO2S 2/1 harness connector B-24 terminal No. 4 and ECM harness connector C-62 terminal No. 71 or PCM harness connector C-59 terminal No. 71, then go to step 15.
  7. Disconnect HO2S 2/1 harness connector B-24. Check HO2S 2/1 harness connector B-24 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  8. Check for resistance between ground and HO2S 2/1 harness connector B-24 terminal No. 2. Resistance should be less than 2 ohms. If resistance not as specified, go to next step. If is as specified, go to step 11.
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  10. Check for open or harness damage in circuit between HO2S 2/1 harness connector B-24 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 15. If problem exists, repair it, then go to step 15.
  11. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step. 15.
  12. Check for open or harness damage in circuit between HO2S 2/1 harness connector B-24 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  13. Check for short to ground or harness damage in circuit between HO2S 2/1 harness connector B-24 terminal No. 4 and ECM harness connector C-62 terminal No. 71 or PCM harness connector C-59 terminal No. 71. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  14. Connect test harness to the connector on the HO2S 2/1 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 1/1 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, turn ignition switch to LOCK position, replace the ECM/PCM, then go to next step. If the voltage is not as specified, replace the HO2S 2/1, then go to next step.
  15. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor and other monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135484-S15606817862002022200000) and «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0152 is output, repeat diagnostic procedure. If DTC P0152 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature is more than 122°F (50°C). Engine speed is 1250-3000 RPM. Volumetric efficiency is 20-60 percent. Engine is under closed loop air/fuel control and throttle is open. Short-term trim is more than -30, but less than 25 percent. More than 3 seconds have elapsed after the above mentioned conditions have been met. Monitoring time is 12 seconds by 7 times. Judgement criteria is when the HO2S 2/1 lean/rich signals alternate 11 times or less for 12 seconds.

The most likely causes for this code to be set are

  1. HO2S 2/1 Deteriorated
  2. ECM/PCM Failed

If sensor switch time is longer than the judgement criteria due to the scan tool OBD-II test MODE - HO2S TEST RESULTS, it is assumed that the HO2S 2/1 has deteriorated. If it is short, it is assumed that the harness is damaged or has a short circuit. If the HO2S signal voltage has not changed even once (lean/rich) after the DTC was erased, the sensor switch time will display as "0" seconds.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 11: HEATED OXYGEN SENSOR BANK 2, SENSOR 1. Warm engine to normal operating temperature. When engine is held at 2500 RPM, HO2S 2/1 output voltage should alternate between 0.4 volt or less and 0.6-1.0 volt 10 times or more within 10 seconds. If scan tool readings are not as specified, turn ignition switch to LOCK position, replace HO2S 2/1, then go to next step. If scan tool readings are as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0153 is output, repeat diagnostic procedure. If DTC P0153 is not output, this diagnosis is complete.

Check condition is when 30 seconds or more have passed since the starting sequence was completed. Engine coolant temperature is more than 169°F (76°C). Engine speed is more than 1200 RPM. Volumetric efficiency is more than 30 percent. Throttle position sensor voltage is less than 4 volts. DTC set conditions are not monitored when fuel is being shut off. Monitor runs for 30 seconds. Judgement criteria is when HO2S 2/1 voltage does not get across 0.5 volt within about 30 seconds.

The most likely causes for this code to be set are

  1. HO2S 2/1 Deteriorated
  2. Open Circuit In HO2S 2/1 Output Line
  3. Open Circuit In HO2S 2/1 Ground Line
  4. ECM/PCM Failed

When the HO2S 2/1 begins to deteriorate, the HO2S 2/1 output voltage will deviate from the voltage when the sensor was new (normally 0.5 volt at stoichiometric ratio). This deviation will be corrected by the HO2S 2/2. If the HO2S 2/2 responds poorly because it has deteriorated, it will improperly correct the HO2S 2/1. Thus, even when closed loop control is being effected, the fluctuation of the HO2S 2/1 output voltage decreases, without intersecting with 0.5 volt. As a result, there is a possibility of DTC P0154 being stored in memory.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 59: HEATED OXYGEN SENSOR BANK 2, SENSOR 2. Warm engine to normal operating temperature. When engine is revved, HO2S 2/2 output voltage should read 0.6-1.0 volt. When the engine is idling, the output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, refer to «DTC P0157: HEATED OXYGEN SENSOR CIRCUIT LOW VOLTAGE (BANK 2 SENSOR 2)»(ref-135484-S15071634322002022200000), «DTC P0158: HEATED OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK 2 SENSOR 2)»(ref-135484-S22940339872002120400000) and «DTC P0159: HEATED OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 2 SENSOR 2)»(ref-135484-S42029536012002022200000).
  2. Check for exhaust leaks. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  3. Check intake system for vacuum leaks. If problem does not exist, turn ignition switch to LOCK position, then go to next step. If problem exists, repair it, then go to step 12.
  4. Disconnect HO2S 2/1 harness connector B-24. Check HO2S 2/1 harness connector B-24 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  5. Connect test harness to the connector on the HO2S 2/1 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 2/1 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, turn ignition switch to LOCK position, then go to next step. If the voltage is not as specified, turn ignition switch to LOCK position, replace the HO2S 2/1, then go to step 12.
  6. Locate suspect fuel injector and disconnect its harness connector. Check suspect fuel injector harness connector for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  7. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector, then go to step 12.
  8. Disconnect ECM harness connectors C-51 and C-62 or PCM harness connectors C-52 and C-59. Check ECM harness connectors C-51 and C-62 or PCM harness connectors C-52 and C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  9. Check for harness damage between HO2S 2/1 harness connector B-24 terminal No. 4 and ECM harness connector C-62 terminal No. 71 or PCM harness connector C-59 terminal No. 71. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  10. Check for harness damage between fuel injector harness connector B-02 terminal No. 2 (cylinder No. 2) and ECM harness connector C-51 terminal No. 9 or PCM harness connector C-52 terminal No. 9. Check for harness damage between fuel injector harness connector B-06 terminal No. 2 (cylinder No. 4) and ECM harness connector C-51 terminal No. 2 or PCM harness connector C-52 terminal No. 2. Check for harness damage between fuel injector harness connector B-25 terminal No. 2 (cylinder No. 6) and ECM harness connector C-51 terminal No. 25 or PCM harness connector C-52 terminal No. 25. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  11. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Fuel pressure should be 39 psi (270 kPa) at idle with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) at idle with fuel pressure regulator vacuum line disconnected. If fuel pressure is normal, replace ECM/PCM, then go to next step. If fuel pressure is not normal, repair it, then go to next step.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0154 is output, repeat diagnostic procedure. If DTC P0154 is not output, this diagnosis is complete.

Check condition is when 60 seconds have elapsed since the start of the previous monitoring. Engine coolant temperature is more than 68°F (20°C). While HO2S 2/1 heater is on. Battery voltage is 11-16 volts. Judgement criteria is when HO2S 2/1 heater current has continued to be less than 0.16 amp or more than 7.5 amps, for 4 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In HO2S 2/1 Heater Circuit
  2. Open Circuit In HO2S 2/1 Heater
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Disconnect HO2S 2/1 harness connector B-24. Check HO2S 2/1 harness connector B-24 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  2. Connect test harness to the connector on the HO2S 2/1 (component side). Measure resistance between HO2S 2/1 connector terminals No. 1 (Red clip) and No. 3 (Blue clip). (Scheme 42) Resistance should be 4.5-8.0 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace HO2S 2/1, then go to step 12.
  3. Turn ignition switch to ON position. Measure voltage between ground and HO2S 2/1 harness connector B-24 terminal No. 1. Battery voltage should exist. If battery voltage does not as exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 5.
  4. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and HO2S 2/1 harness connector B-24 terminal No. 1, then go to step 12.
  5. Reconnect HO2S 2/1 harness connector B-24. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 3 or PCM harness connector C-52 terminal No. 3 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 8.
  6. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  7. Check for open or short to ground in circuit between HO2S 2/1 harness connector B-24 terminal No. 3 and ECM harness connector C-51 terminal No. 3 or PCM harness connector C-52 terminal No. 3. If problem does not exist, replace ECM/PCM, then go to step 12. If problem exists, repair it, then go to step 12.
  8. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12. If problem does not exist, go to next step.
  9. Check for harness damage between MFI relay harness connector A-18X terminal No. 4 and HO2S 2/1 harness connector B-24 terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  10. Check for harness damage between HO2S 2/1 harness connector B-24 terminal No. 3 and ECM harness connector C-51 terminal No. 3 or PCM harness connector C-52 terminal No. 3. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0155 is output, replace ECM/PCM, then go to next step. If DTC P0155 is not output, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0155 is output, repeat diagnostic procedure. If DTC P0155 is not output, this diagnosis is complete.

Check condition is when 3 minutes or more have passed since the starting sequence was completed, HO2S 2/2 signal voltage has continued to be 0.15 volt or less, engine coolant temperature is more than 169°F (76°C), engine speed is more than 1200 RPM and volumetric efficiency is more 25 percent. At least 20 seconds have passed since fuel shut-off control was cancelled. The HO2S 2/1 outputs 0.5 volt or more. After the ignition switch is turned to ON position, the changes in the output voltage of the HO2S 2/2 is less than 0.078 volt. Monitoring time is 10 seconds. Judgement criteria is when making the air/fuel ratio 15 percent richer for 10 seconds does not result in raising the HO2S 2/2 output voltage to more than 0.15 volt. Only one monitor is performed during one drive cycle.

The most likely causes for this code to be set are

  1. HO2S 2/2 Failed
  2. Open Circuit In HO2S 2/2 Output Line
  3. Short Circuit In HO2S 2/2 Output Line
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 59: HEATED OXYGEN SENSOR BANK 2, SENSOR 2. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 2/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect HO2S 2/2 harness connector B-23. Connect test harness to the connector on the HO2S 2/2 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 2/2 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, turn ignition switch to LOCK position, then go to next step. If the voltage is not as specified, replace the HO2S 2/2, then go to step 5.
  3. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 2/2 harness connector B-23 and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 5.
  4. Check for short to ground in circuit between front HO2S 2/2 harness connector B-23 terminal No. 4 and ECM harness connector C-62 terminal No. 73 or PCM harness connector C-59 terminal No. 73. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  5. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0157 is output, repeat diagnostic procedure. If DTC P0157 is not output, this diagnosis is complete.

Check condition is when 3 minutes or more have passed since the starting sequence was completed, HO2S 2/2 signal voltage has continued to be 0.15 volt or less, engine coolant temperature is more than 169°F (76°C), engine speed is more than 1200 RPM and volumetric efficiency is more 25 percent. Monitoring time is 7 seconds. Judgement criteria is when input voltage supplied to the ECM/PCM interface circuit is more than 4.5 volts when 5 volts is applied to the HO2S 2/2 output line through a resistor. Only one monitor is performed during one drive cycle.

The most likely causes for this code to be set are

  1. HO2S 2/2 Failed
  2. Open Circuit In HO2S 2/2 Output Line
  3. Open Circuit In HO2S 2/2 Ground Line
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 59: HEATED OXYGEN SENSOR BANK 2, SENSOR 2. Warm engine to normal operating temperature. When engine is repeatedly revved, HO2S 2/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Start the engine and run at idle. Measure voltage between ground and HO2S 2/2 harness connector B-23 terminal No. 4 by backprobing. Warm engine to normal operating temperature. When engine is revved, HO2S 2/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to step 7.
  3. Measure voltage between ground and ECM harness connector C-62 terminal No. 73 or PCM harness connector C-59 terminal No. 73 by backprobing. Warm engine to normal operating temperature. When engine is held at 2500 RPM, HO2S 2/2 output voltage should alternate between zero volts and 0.6-1.0 volt. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to step 6.
  4. Disconnect HO2S 2/2 harness connector B-23. Check HO2S 2/2 harness connector B-23 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  5. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 59: HEATED OXYGEN SENSOR BANK 2, SENSOR 2. Warm engine to normal operating temperature. When engine is revved, HO2S 2/2 output voltage should alternate between about zero volts and 0.6-1.0 volt. If sensor is not operating properly, replace ECM/PCM, then go to step 15. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  6. Disconnect HO2S 2/2 harness connector B-23 and ECM harness connector C-62 or PCM harness connector C-59. Check HO2S 2/2 harness connector B-23 and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 15. If problem does not exist, repair open or harness damage in circuit between HO2S 2/2 harness connector B-23 terminal No. 4 and ECM harness connector C-62 terminal No. 71 or PCM harness connector C-59 terminal No. 71, then go to step 15.
  7. Disconnect HO2S 2/2 harness connector B-23. Check HO2S 2/2 harness connector B-23 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  8. Measure resistance between ground and HO2S 2/2 harness connector B-23 terminal No. 2. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 11.
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  10. Check for open or harness damage in circuit between HO2S 2/2 harness connector C-23 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM then go to step 15. If problem exists, repair it, then go to step 15.
  11. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  12. Check for harness damage between HO2S 2/2 harness connector C-23 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  13. Check for short to ground or harness damage in circuit between HO2S 2/2 harness connector C-23 terminal No. 4 and ECM harness connector C-62 terminal No. 71 or PCM harness connector C-59 terminal No. 71. If problem does not exist, go to next step. If problem exists, repair it, then go to step 15.
  14. Disconnect HO2S 2/2 harness connector B-23. Connect test harness to the connector on the HO2S 2/2 (component side). Warm up the engine until engine coolant is 176°F (80°C) or more. Use the jumper wires to connect terminal No. 1 (Red clip) to the positive battery terminal and terminal No. 3 (Blue clip) to the negative battery terminal. (Scheme 42) Connect a DVOM between terminal No. 2 (Black clip) and terminal No. 4 (White clip). While repeatedly revving the engine, measure the HO2S 2/2 output voltage. Voltage should be 0.6-1.0 volt. If the voltage is as specified, replace ECM/PCM then go to next step. If the voltage is not as specified, replace the HO2S 2/2, then go to next step.
  15. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor and other monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135484-S15606817862002022200000) and «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0158 is output, repeat diagnostic procedure. If DTC P0158 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature is more than 169°F (76°C), the HO2S 2/1 is active and the cumulative Volume Airflow (VAF) sensor output frequency is more than 4,000 Hz under the following conditions, repeated 3 or more times: drive 1, stop 2. Drive 1 is when engine speed is more than 1500 RPM, volumetric efficiency is more than 40 percent, vehicle speed is more than 18.7 mph, a total of more than 10 seconds have elapsed with the above mentioned conditions, and more than 2 seconds have elapsed with the fuel shut off. Stop 2 is when vehicle speed must be less than 0.9 mph. Judgement criteria is when change in the output voltage of the HO2S 2/2 is less than 0.078 volt. Monitoring stops after fuel has been shut off for more than 38 seconds.

The most likely causes for this code to be set are

  1. HO2S 2/2 Failed
  2. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 59: HEATED OXYGEN SENSOR BANK 2, SENSOR 2. Warm engine to normal operating temperature. After increasing the output voltage 0.15 volt or more by revving the engine, allow engine to idle. Confirm that the output voltage reduces to 0.15 volts or less within 3 seconds. If sensor is not operating properly, turn ignition switch to LOCK position, replace the HO2S 2/2, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor pattern. See «HEATED OXYGEN SENSOR MONITOR»(ref-135484-S15606817862002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0159 is output, repeat diagnostic procedure. If DTC P0159 is not output, this diagnosis is complete.

Check condition is when 60 seconds have elapsed since the start of the previous monitoring, engine coolant temperature is more than 68°F (20°C), the HO2S 2/1 heater is on and battery positive voltage is 11-16 volts. Judgment criteria is when heater current of the HO2S 1/2 heater is less than 0.16 amp or more than 5.0 amps for 4 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In HO2S 2/2 Heater Circuit
  2. Open Circuit In HO2S 2/2 Heater
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Disconnect HO2S 2/2 harness connector B-23. Check HO2S 2/2 harness connector B-23 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  2. Connect test harness to the connector on the HO2S 2/2 (component side). Measure resistance between HO2S 2/2 connector terminals No. 1 (Red clip) and No. 3 (Blue clip). (Scheme 42) Resistance should be 11-18 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace HO2S 2/2 then go to step 12.
  3. Turn ignition switch to ON position. Measure voltage between ground and HO2S 2/2 harness connector B-23 terminal No. 1. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position then go to next step. If battery voltage exists, turn ignition switch to LOCK position then go to step 5.
  4. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and HO2S 2/2 harness connector B-23 terminal No. 1, then go to step 12.
  5. Reconnect HO2S 2/2 harness connector B-23. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 26 or PCM harness connector C-52 terminal No. 26 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 8.
  6. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  7. Check for open or short to ground in circuit between HO2S 2/2 harness connector B-23 terminal No. 3 and ECM harness connector C-51 terminal No. 26 or PCM harness connector C-52 terminal No. 26. If problem does not exist, replace ECM/PCM, then go to step 12. If problem exists, repair it, then go to step 12.
  8. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  9. Check for harness damage in circuit between HO2S 2/2 harness connector B-23 terminal No. 1 and MFI relay harness connector A-18X terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  10. Check for harness damage in circuit between HO2S 2/2 harness connector B-23 terminal No. 3 and ECM harness connector C-51 terminal No. 26 or PCM harness connector C-52 terminal No. 26. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0161 is output, replace ECM/PCM, then go to next step. If DTC P0161 is not output, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0161 is output, repeat diagnostic procedure. If DTC P0161 is not output, this diagnosis is complete.
  1. Check condition is when engine coolant temperature is less than 212°F (100°C) when engine is started. Intake air temperature is less than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Airflow (VAF) sensor output frequency is 75 Hz or more. Judgment criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 7.4 percent for 5 seconds.
  2. Check condition is when engine coolant temperature is less than 212°F (100°C) when engine is started. Intake air temperature is less than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). VAF sensor output frequency is 75 Hz or less. Judgement criteria is when long-term fuel has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 12.5 for 5 seconds.
  3. Check condition is when engine coolant temperature is more than 212°F (100°C) when engine is started. Intake air temperature is more than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). VAF sensor output frequency is 75 Hz or more. Judgement criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 12.5 percent for 5 seconds.
  4. Check condition is when engine coolant temperature is more than 212°F (100°C) when engine is started. Intake air temperature is more than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Airflow (VAF) sensor output frequency is less than 75 Hz or less. Judgement criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 22.3 percent for 5 seconds.
  5. Check condition is when engine coolant temperature is more than 171°F (77°C). Engine is in closed loop air/fuel control. Judgement criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be 25.0 percent for 5 seconds.

The most likely causes for this code to be set are

  1. Exhaust System Leak
  2. VAF Sensor Failed
  3. Fuel Injector No. 1, 3 &/Or 5 Failed
  4. Incorrect Fuel Pressure
  5. Air Drawn In From Gaps In Gasket, Seals, Etc.
  6. Right Bank Heated Oxygen Sensor (HO2S) Failed
  7. Engine Coolant Temperature (ECT) Sensor Failed
  8. Intake Air Temperature (IAT) Sensor Failed
  9. Barometric Pressure (BARO) Sensor Failed
  10. Incorrect Or Contaminated Fuel Used
  11. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Check exhaust system for leaks. If problem does not exist, go to next step. If problem exists, repair it, then go to step 16 .
  2. Check intake system for vacuum leaks. If problem does not exist, go to next step. If problem exists, repair it, then go to step 16 .
  3. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 12: VOLUME AIRFLOW SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). When idling, reading should be 17-46 Hz (2.2-5.7 grams per second). When engine speed is 2500 RPM, reading should be 63-103 Hz (9.0-14.7 grams per second). If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0101: VOLUME AIRFLOW CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S31277963332002022200000) and «DTC P0102: VOLUME AIRFLOW CIRCUIT LOW INPUT»(ref-135484-S41933835872002022200000) .
  4. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. The intake air temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT MALFUNCTION»(ref-135484-S08103887492002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S40282798662002120400000) or «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S19257297252002120400000) .
  5. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S29119954222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S20543585982002022200000) or «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S38870091092002022200000) .
  6. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S04947395752002120400000) and «DTC P0107: BAROMETRIC PRESSURE CIRCUIT LOW INPUT»(ref-135484-S11572049882002022200000) or «DTC P0108: BAROMETRIC PRESSURE CIRCUIT HIGH INPUT»(ref-135484-S24680232042002022200000) .
  7. Disconnect intermediate connector B-48. Check intermediate connector B-48 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 16 .
  8. Measure resistance of fuel injector No. 1 circuit between intermediate connector B-48 terminals No. 1 and 2. Measure resistance of fuel injector No. 3 circuit between intermediate connector B-48 terminals No. 1 and 3. Measure resistance of fuel injector No. 5 circuit between intermediate connector B-48 terminals No. 1 and 4. Resistance of each circuit should be 13-16 ohms at 68°F (20°C). If any resistance is not as specified, go to next step. If all resistances are as specified, go to step 11 .
  9. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Check suspect fuel injector harness connector for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 16 .
  10. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, repair harness damage in circuit between fuel injector and intermediate connector B-48, then go to step 16 . If resistance is not as specified, replace fuel injector, then go to step 16 .
  11. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 16 .
  12. Check for harness damage between fuel injector No. 1 harness connector B-01 terminal No. 2 and ECM harness connector C-51 terminal No. 1 or PCM harness connector C-52 terminal No. 1. Check for harness damage between fuel injector No. 3 harness connector B-05 terminal No. 2 and ECM harness connector C-51 terminal No. 24 or PCM harness connector C-52 terminal No. 24. Check for harness damage between fuel injector No. 5 harness connector B-26 terminal No. 2 and ECM harness connector C-51 terminal No. 10 or PCM harness connector C-52 terminal No. 10. If problem does not exist, go to next step. If problem exists, repair it, then go to step 16 .
  13. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Fuel pressure should be 39 psi (270 kPa) at idle with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) at idle with fuel pressure regulator vacuum line disconnected. If fuel pressure is normal, go to next step. If fuel pressure is not normal, repair it, then go to step 16 .
  14. Check for entry of foreign matter (water, kerosene, etc.) into fuel. If problem does not exist, go to next step. If problem exists, replace the fuel. Then go to step 16 .
  15. Turn ignition switch to LOCK position. Replace suspect right bank fuel injector(s). Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0171 is output, replace ECM/PCM, then go to next step. If DTC P0171 is not output, this diagnosis is complete.
  16. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0171 output, repeat diagnostic procedure. If DTC P0171 not output, this diagnosis is complete.
  1. Check condition is when under the closed loop air/fuel ratio control, the engine coolant temperature is more than 171°F (77°C) and Volume Airflow (VAF) sensor output frequency is 75 Hz or more. Judgment criteria is when long-term fuel trim has continued to be less than -12.5 percent for 5 seconds or short-term fuel trim has continued to be less than -7.4 percent for 5 seconds.
  2. Check condition is when under the closed loop air/fuel ratio control, the engine coolant temperature is more than 171°F (77°C) and VAF sensor output frequency is 75 Hz or less. Judgment criteria is when long-term fuel trim has continued to be less than -12.5 percent for 5 seconds or short-term fuel trim has continued to be less than -12.5 percent for 5 seconds.
  3. Check condition is when under the closed loop air/fuel ratio control, the engine coolant temperature is more than 171°F (77°C). Judgment criteria is when long-term fuel trim has continued to be less than -12.5 percent for 5 seconds or short-term fuel trim has continued to be less than -30 percent for 5 seconds.

The most likely causes for this code to be set are

  1. VAF Sensor Failed
  2. Fuel Injector No. 1, 3 &/Or 5 Failed
  3. Incorrect Fuel Pressure
  4. Right Bank Heated Oxygen Sensor (HO2S) Failed
  5. Engine Coolant Temperature (ECT) Sensor Failed
  6. Intake Air Temperature (IAT) Sensor Failed
  7. Barometric Pressure (BARO) Sensor Failed
  8. Exhaust System Leak
  9. Incorrect Or Contaminated Fuel Used
  10. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 12: VOLUME AIRFLOW SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). When idling, reading should be 17-46 Hz (2.2-5.7 grams per second). When engine speed is 2500 RPM, reading should be 63-103 Hz (9.0-14.7 grams per second). If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0101: VOLUME AIRFLOW CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S31277963332002022200000) and «DTC P0102: VOLUME AIRFLOW CIRCUIT LOW INPUT»(ref-135484-S41933835872002022200000) .
  2. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. The intake air temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT MALFUNCTION»(ref-135484-S08103887492002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S40282798662002120400000) or «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S19257297252002120400000) .
  3. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S29119954222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S20543585982002022200000) or «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S38870091092002022200000) .
  4. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S04947395752002120400000) and «DTC P0107: BAROMETRIC PRESSURE CIRCUIT LOW INPUT»(ref-135484-S11572049882002022200000) or «DTC P0108: BAROMETRIC PRESSURE CIRCUIT HIGH INPUT»(ref-135484-S24680232042002022200000) .
  5. Disconnect intermediate connector B-48. Check intermediate connector B-48 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 10 .
  6. Measure resistance of fuel injector No. 1 circuit between intermediate connector B-48 terminals No. 1 and 2. Measure resistance of fuel injector No. 3 circuit between intermediate connector B-48 terminals No. 1 and 3. Measure resistance of fuel injector No. 5 circuit between intermediate connector B-48 terminals No. 1 and 4. Resistance of each circuit should be 13-16 ohms at 68°F (20°C). If any resistance is not as specified, go to next step. If all resistances are as specified, go to step 8 .
  7. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, repair harness damage in circuit between fuel injector and intermediate connector B-48, then go to step 10 . If resistance is not as specified, replace fuel injector, then go to step 10 .
  8. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Fuel pressure should be 39 psi (270 kPa) at idle with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) at idle with fuel pressure regulator vacuum line disconnected. If fuel pressure is normal, go to next step. If fuel pressure is not normal, repair it, then go to step 10 .
  9. Turn ignition switch to LOCK position. Replace suspect right bank fuel injector(s). Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0172 is output, replace ECM/PCM, then go to next step. If DTC P0172 is not output, this diagnosis is complete.
  10. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0172 output, repeat diagnostic procedure. If DTC P0172 not output, this diagnosis is complete.
  1. Check condition is when engine coolant temperature is less than 212°F (100°C) when engine is started. Intake air temperature is less than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Airflow (VAF) sensor output frequency is 75 Hz or more. Judgment criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 7.4 percent for 5 seconds.
  2. Check condition is when engine coolant temperature is less than 212°F (100°C) when engine is started. Intake air temperature is less than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). VAF sensor output frequency is 75 Hz or less. Judgement criteria is when long-term fuel has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 12.5 for 5 seconds.
  3. Check condition is when engine coolant temperature is more than 212°F (100°C) when engine is started. Intake air temperature is more than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). VAF sensor output frequency is 75 Hz or more. Judgement criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 12.5 percent for 5 seconds.
  4. Check condition is when engine coolant temperature is more than 212°F (100°C) when engine is started. Intake air temperature is more than 140°F (60°C) when engine is started. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). VAF sensor output frequency is less than 75 Hz or less. Judgement criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be more than 22.3 percent for 5 seconds.
  5. Check condition is when engine coolant temperature is more than 171°F (77°C). Engine is in closed loop air/fuel control. Judgement criteria is when long-term fuel trim has continued to be more than 12.5 percent for 5 seconds or short-term fuel trim has continued to be 25.0 percent for 5 seconds.

The most likely causes for this code to be set are

  1. Exhaust system leak.
  2. VAF Sensor Failed
  3. Fuel Injector No. 2, 4 &/Or 6 Failed
  4. Incorrect Fuel Pressure
  5. Air Drawn In From Gaps In Gasket, Seals, Etc.
  6. Left Bank Heated Oxygen Sensor (HO2S) Failed
  7. Engine Coolant Temperature (ECT) Sensor Failed
  8. Intake Air Temperature (IAT) Sensor Failed
  9. Barometric Pressure (BARO) Sensor Failed
  10. Incorrect Or Contaminated Fuel Used
  11. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Check exhaust system for leaks. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  2. Check intake system for vacuum leaks. If problem does not exist, go to next step. If problem exists, repair as necessary, then go to step 14 .
  3. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 12: VOLUME AIRFLOW SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). When idling, reading should be 17-46 Hz (2.2-5.7 grams per second). When engine speed is 2500 RPM, reading should be 63-103 Hz (9.0-14.7 grams per second). If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0101: VOLUME AIRFLOW CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S31277963332002022200000) and «DTC P0102: VOLUME AIRFLOW CIRCUIT LOW INPUT»(ref-135484-S41933835872002022200000) .
  4. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. The intake air temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT MALFUNCTION»(ref-135484-S08103887492002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S40282798662002120400000) or «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S19257297252002120400000) .
  5. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S29119954222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S20543585982002022200000) or «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S38870091092002022200000) .
  6. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S04947395752002120400000) and «DTC P0107: BAROMETRIC PRESSURE CIRCUIT LOW INPUT»(ref-135484-S11572049882002022200000) or «DTC P0108: BAROMETRIC PRESSURE CIRCUIT HIGH INPUT»(ref-135484-S24680232042002022200000) .
  7. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Check suspect fuel injector harness connector for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  8. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector, then go to step 14 .
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  10. Check for harness damage between fuel injector No. 2 harness connector B-02 terminal No. 2 and ECM harness connector C-51 terminal No. 9 or PCM harness connector C-52 terminal No. 9. Check for harness damage between fuel injector No. 4 harness connector B-06 terminal No. 2 and ECM harness connector C-51 terminal No. 2 or PCM harness connector C-52 terminal No. 2. Check for harness damage between fuel injector No. 5 harness connector B-25 terminal No. 2 and ECM harness connector C-51 terminal No. 25 or PCM harness connector C-52 terminal No. 25. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  11. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Fuel pressure should be 39 psi (270 kPa) at idle with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) at idle with fuel pressure regulator vacuum line disconnected. If fuel pressure is normal, go to next step. If fuel pressure is not normal, repair it, then go to step 14 .
  12. Check for entry of foreign matter (water, kerosene, etc.) into fuel. If problem does not exist, go to next step. If problem exists, replace the fuel. Then go to step 14 .
  13. Turn ignition switch to LOCK position. Replace suspect fuel injector(s). Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0174 is output, replace ECM/PCM, then go to next step. If DTC P0174 is not output, this diagnosis is complete.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0174 output, repeat diagnostic procedure. If DTC P0174 not output, this diagnosis is complete.
  1. Check condition is when under the closed loop air/fuel ratio control, the engine coolant temperature is more than 171°F (77°C) and Volume Airflow (VAF) sensor output frequency is 75 Hz or more. Judgment criteria is when long-term fuel trim has continued to be less than -12.5 percent for 5 seconds or short-term fuel trim has continued to be less than -7.4 percent for 5 seconds.
  2. Check condition is when under the closed loop air/fuel ratio control, the engine coolant temperature is more than 171°F (77°C) and VAF sensor output frequency is 75 Hz or less. Judgment criteria is when long-term fuel trim has continued to be less than -12.5 percent for 5 seconds or short-term fuel trim has continued to be less than -12.5 percent for 5 seconds.
  3. Check condition is when under the closed loop air/fuel ratio control, the engine coolant temperature is more than 171°F (77°C). Judgment criteria is when long-term fuel trim has continued to be less than -12.5 percent for 5 seconds or short-term fuel trim has continued to be less than -7.4 percent for 5 seconds.

The most likely causes for this code to be set are

  1. VAF Sensor Failed
  2. Fuel Injector No. 2, 4 &/Or 6 Failed
  3. Incorrect Fuel Pressure
  4. Left Bank Heated Oxygen Sensor (HO2S) Failed
  5. Engine Coolant Temperature (ECT) Sensor Failed
  6. Intake Air Temperature (IAT) Sensor Failed
  7. Barometric Pressure (BARO) Sensor Failed
  8. Exhaust System Leak
  9. Incorrect Or Contaminated Fuel Used
  10. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 12: VOLUME AIRFLOW SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). When idling, reading should be 17-46 Hz (2.2-5.7 grams per second). When engine speed is 2500 RPM, reading should be 63-103 Hz (9.0-14.7 grams per second). If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0101: VOLUME AIRFLOW CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S31277963332002022200000) and «DTC P0102: VOLUME AIRFLOW CIRCUIT LOW INPUT»(ref-135484-S41933835872002022200000) .
  2. Set scan tool to the data reading mode for data list item 13: INTAKE AIR TEMPERATURE SENSOR. The intake air temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT MALFUNCTION»(ref-135484-S08103887492002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S40282798662002120400000) or «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S19257297252002120400000) .
  3. Set scan tool to the data reading mode for data list item 21: ENGINE COOLANT TEMPERATURE SENSOR. The engine coolant temperature and temperature shown with the scan tool should approximately match. If sensor is operating properly, go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S29119954222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135484-S20543585982002022200000) or «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135484-S38870091092002022200000) .
  4. Set scan tool to the data reading mode for data list item 25: BAROMETRIC PRESSURE SENSOR. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135484-S28653548692002022200000) table. If sensor is operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, then go to «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135484-S04947395752002120400000) and «DTC P0107: BAROMETRIC PRESSURE CIRCUIT LOW INPUT»(ref-135484-S11572049882002022200000) or «DTC P0108: BAROMETRIC PRESSURE CIRCUIT HIGH INPUT»(ref-135484-S24680232042002022200000) .
  5. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector, then go to step 8 .
  6. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Fuel pressure should be 39 psi (270 kPa) at idle with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) at idle with fuel pressure regulator vacuum line disconnected. If fuel pressure is normal, go to next step. If fuel pressure is not normal, repair it, then go to step 8 .
  7. Turn ignition switch to LOCK position. Replace suspect fuel injector(s). Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0175 is output, replace ECM/PCM, then go to next step. If DTC P0175 is not output, this diagnosis is complete.
  8. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135484-S06995383792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0175 output, repeat diagnostic procedure. If DTC P0175 not output, this diagnosis is complete.

Check condition is when the difference between engine coolant temperature and intake air temperature is 41°F (5°C) or less when the engine is started, engine coolant temperature is 14-97°F (-10 to 36°C) or more than 140°F (60°C) when engine is started, and maximum vehicle speed is more than 17 mph after the starting sequence has been completed. Judgement criteria is when the difference between fuel temperature and engine coolant temperature is 59°F (15°C) or more when the engine is started.

The most likely causes for this code to be set are

  1. Open Or Shorted Fuel Temperature Sensor Circuit, Or Loose Connector
  2. Fuel Temperature Sensor Failed
  3. ECM/PCM Failed

If the engine and the radiator have been flushed repeatedly when the engine coolant temperature was high (or the fuel temperature was high), a DTC could be output. Because this is not a failure, the DTC must be erased. Ensure vehicle is test driven in accordance with the OBD-II drive cycle other monitor pattern in order to verify that a DTC will not be output. See OTHER MONITOR under OBD-II DRIVE CYCLES under VERIFYING REPAIRS

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 4A: FUEL TEMPERATURE SENSOR. Scan tool reading should be approximately the same as the outside temperature when the engine is cooled. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect fuel temperature sensor harness connector D-17. Check fuel temperature sensor harness connector D-17 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  3. Measure resistance between fuel temperature sensor connector (component side) terminals No. 1 and 3. Resistance should be 0.5-12.0 k/ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel temperature sensor, then go to step 12 .
  4. Check resistance between ground and fuel temperature sensor harness connector D-17 terminal No. 1. Resistance should be less than 2 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open or harness damage in circuit between ground and fuel temperature sensor harness connector D-17, then go to step 12 .
  5. Turn ignition switch to ON position. Measure voltage between ground and fuel temperature sensor harness connector D-17 terminal No. 3. Voltage should be 4.5-4.9 volts. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 10 .
  6. Measure voltage between ground and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal No. 51 by backprobing. Compare voltage against specification. See «FUEL TEMPERATURE SENSOR OUTPUT VOLTAGE»(ref-135484-S10455707012003010600000) table. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 8 . FUEL TEMPERATURE SENSOR OUTPUT VOLTAGE Fuel Temperature - °F (°C) Voltage 32 (0) 2.7-3.1 68 (20) 2.1-2.5 104 (40) 1.6-2.0 176 (80) 0.8-1.2
  7. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, repair open in circuit between fuel temperature sensor harness connector D-17 terminal No. 3 and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal 51, then go to step 12 .
  8. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  9. Check for short to ground in circuit between fuel temperature sensor harness connector D-17 terminal No. 3 and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal No. 51. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  10. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  11. Check intermediate connectors C-28 and C-90 for loose, damaged or corroded terminals. If problem exists, repair it, then go to next step. If problem does not exist, check for harness damage between fuel temperature sensor harness connector D-17 terminal No. 3 and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal 51. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0181 is output, repeat diagnostic procedure. If DTC P0181 is not output, this diagnosis is complete.

Two or more seconds have passed since the starting sequence has been completed. Judgement criteria is when the sensor output voltage has continued to be 0.1 volt or less for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Shorted Fuel Temperature Sensor Circuit, Or Loose Connector
  2. Fuel Temperature Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 4A: FUEL TEMPERATURE SENSOR. Scan tool reading should be approximately the same as the outside temperature when the engine is cooled. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect fuel temperature sensor harness connector D-17. Measure resistance between fuel temperature sensor connector (component side) terminals No. 1 and 3. Resistance should be 0.5-12.0 k/ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel temperature sensor, then go to step 5 .
  3. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check fuel temperature sensor harness connector D-17 and ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 5 .
  4. Check intermediate connectors C-28 and C-90 for loose, damaged or corroded terminals. If problem exists, repair it, then go to next step. If problem does not exist, check for short to ground in circuit between fuel temperature sensor harness connector D-17 terminal No. 3 and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal No. 51. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it , then go to next step.
  5. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0181 is output, repeat diagnostic procedure. If DTC P0181 is not output, this diagnosis is complete.

Two or more seconds have passed since the starting sequence has been completed. Judgement criteria is when the sensor output voltage has continued to be 4.6 volt or more for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Shorted Fuel Temperature Sensor Circuit, Or Loose Connector
  2. Fuel Temperature Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 4A: FUEL TEMPERATURE SENSOR. Scan tool reading should be approximately the same as the outside temperature when the engine is cooled. If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect fuel temperature sensor harness connector D-17. Check fuel temperature sensor harness connector D-17 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  3. Measure resistance between fuel temperature sensor connector (component side) terminals No. 1 and 3. Resistance should be 0.5-12.0 k/ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel temperature sensor, then go to step 11 .
  4. Turn ignition switch to ON position. Measure voltage between ground and fuel temperature sensor harness connector D-17 terminal No. 3. Voltage should be 4.5-4.9 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 8 .
  5. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal No. 51 by backprobing. Voltage should be 4.5-4.9 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 7 .
  6. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 11 . If problem does not exist, check intermediate connectors C-28 and C-90 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 11 . If problem does not exist, repair open in circuit between fuel temperature sensor harness connector D-17 terminal No. 3 and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal 51, then go to step 11 .
  7. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to step 11 . If problem exists, repair it, then go to step 11 .
  8. Check resistance between ground and fuel temperature sensor harness connector D-17 terminal No. 1. Resistance should be less than 2 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open or harness damage in circuit between ground and fuel temperature sensor harness connector D-17, then go to step 11 .
  9. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  10. Check intermediate connectors C-28 and C-90 for loose, damaged or corroded terminals. If problem exists, repair it, then go to next step. If problem does not exist, check for open or harness damage in circuit between fuel temperature sensor harness connector D-17 terminal No. 3 and ECM harness connector C-62 terminal No. 96 or PCM harness connector C-55 terminal No. 51. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0183 is output, repeat diagnostic procedure. If DTC P0183 is not output, this diagnosis is complete.

Check condition is when engine speed is less than 1000 RPM and Throttle Position (TP) sensor output voltage is less than 1.16 volt. Judgement criteria is when fuel injector coil surge voltage (battery voltage plus 2 volts) has not been detected for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In Fuel Injector Circuit Or Loose Connector
  2. Fuel Injector Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the actuator testing mode for data list item 01, 03, 05: INJECTORS. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). Using scan tool, turn each fuel injector off, then on. As each fuel injector is turned off, there should be a change in idle speed and/or smoothness. Idle should improve when fuel injector is turned back on. If fuel injectors do not perform as specified, turn ignition switch to LOCK position, then go to next step. If fuel injectors perform as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect intermediate connector B-48. Check intermediate connector B-48 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  3. Measure resistance of fuel injector No. 1 circuit between intermediate connector B-48 terminals No. 1 and 2. Measure resistance of fuel injector No. 3 circuit between intermediate connector B-48 terminals No. 1 and 3. Measure resistance of fuel injector No. 5 circuit between intermediate connector B-48 terminals No. 1 and 4. Resistance of each circuit should be 13-16 ohms at 68°F (20°C). If any resistance is not as specified, go to next step. If all resistances are as specified, go to step 6.
  4. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Check suspect fuel injector harness connector for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  5. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, repair open or short to ground in circuit between fuel injector and intermediate connector B-48, then go to step 12. If resistance is not as specified, replace fuel injector, then go to step 12.
  6. Turn ignition switch to ON position. Measure voltage between ground and intermediate connector B-48 terminal No. 1. Battery voltage should exist. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 8.
  7. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and suspect fuel injector harness connector terminal No. 1, then go to step 12.
  8. Check for harness damage to circuit between MFI relay harness connector A-18X terminal No. 4 and intermediate connector B-48 terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  10. Check for open, short to ground or harness damage between suspect fuel injector harness connector and ECM harness connector C-51 or PCM harness connector C-52. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12.
  11. Disconnect intermediate connector B-48 and connect Test Harness (MB998464) between connector halves (All terminals should be connected). Connect the oscilloscope probe to the intermediate connector terminal No. 2 Black clip (cylinder No. 1), No. 3 Blue clip (cylinder No. 3) or No. 4 White clip (cylinder No. 5). If connecting at ECM/PCM, see «ECM/PCM BANK 1 FUEL INJECTOR CIRCUIT TERMINAL IDENTIFICATION»(ref-135484-S25062134602002022200000) table for pick-up points. Start the engine and run at idle. Measure the waveform. The waveform should show a normal pattern. (Scheme 43) If waveform is not normal, replace ECM/PCM, then go to next step. If waveform is normal, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM. ECM/PCM BANK 1 FUEL INJECTOR CIRCUIT TERMINAL IDENTIFICATION Injector No. (1) Terminal No. 1 1 3 24 5 10 (1) On vehicles with Manual Transaxle (M/T), test at ECM harness connector C-51. On vehicles with Automatic Transaxle (A/T), test at PCM harness connector C-52.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0201, P0203 and/or P0205 is output, repeat diagnostic procedure. If DTC P0201, P0203 and P0205 are not output, this diagnosis is complete.

Scheme 43

Scheme 43
Scheme 43

Check condition is when engine speed is less than 1000 RPM and Throttle Position (TP) sensor output voltage is less than 1.16 volt. Judgement criteria is when fuel injector coil surge voltage (battery voltage plus 2 volts) has not been detected for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In Fuel Injector Circuit Or Loose Connector
  2. Fuel Injector Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the actuator testing mode for data list item 02, 04, 06: INJECTORS. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). Using scan tool, turn each fuel injector off, then on. As each fuel injector is turned off, there should be a change in idle speed and/or smoothness. Idle should improve when fuel injector is turned back on. If fuel injectors do not perform as specified, turn ignition switch to LOCK position, then go to next step. If fuel injectors perform as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Remove intake manifold. Locate suspect fuel injector and disconnect its harness connector. Check suspect fuel injector harness connector for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 10.
  3. Measure resistance across suspect fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector, then go to step 10.
  4. Turn ignition switch to ON position. Measure voltage between ground and suspect fuel injector harness connector terminal No. 1. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 6.
  5. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 10. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and suspect fuel injector harness connector terminal No. 1, then go to step 10.
  6. Check for harness damage in circuit between MFI relay harness connector A-18X terminal No. 4 and suspect fuel injector harness connector terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 10.
  7. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 10.
  8. Check for open, short to ground or harness damage between suspect fuel injector harness connector and ECM harness connector C-51 or PCM harness connector C-52. If problem does not exist, go to next step. If problem exists, repair it, then go to step 10.
  9. Disconnect bank 2 fuel injector harness connectors and connect Test Harness (MB991348) between bank 2 fuel injectors and harness connector halves terminal No. 2 (All terminals should be connected). Connect the oscilloscope probe to the suspect fuel injector harness connector terminal No. 2. If connecting at ECM/PCM, see «ECM/PCM BANK 2 FUEL INJECTOR CIRCUIT TERMINAL IDENTIFICATION»(ref-135484-S37018397522003010700000) table for pick-up points. Start the engine and run at idle. Measure the waveform. The waveform should show a normal pattern. (Scheme 43) If waveform is not normal, replace ECM/PCM, then go to next step. If waveform is normal, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM. ECM/PCM BANK 2 FUEL INJECTOR CIRCUIT TERMINAL IDENTIFICATION Injector No. (1) Terminal No. 2 9 4 2 6 25 (1) On vehicles with Manual Transaxle (M/T), test at ECM connector C-51. On vehicles with Automatic Transaxle (A/T), test at PCM connector C-52.
  10. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0202, P0204 and/or P0206 is output, repeat diagnostic procedure. If DTC P0202, P0204 and P0206 are not output, this diagnosis is complete.

Check condition is when engine speed is 440-6000 RPM, engine coolant temperature is more than 14°F (-10°C), intake air temperature is more than 14°F (-10°C), barometric pressure is more than 11 psi (76 kPa) and adaptive learning is complete for the vane which generates a Crankshaft Position (CKP) sensor signal. Engine must be running, excluding gear shifting, deceleration, sudden acceleration/deceleration and A/C compressor switching and the throttle deviation is -0.059-0.059 v/10 ms. Judgement criteria is when misfire has occurred more frequently than allowed during the last 200 revolutions when the catalyst temperature is more than 1742°F (950°C), or misfire has occurred in 20 or more of the last 1000 revolutions (corresponding to 1.5 times the limit of emission standard). Change in the angular acceleration of the crankshaft is used for misfire detection.

The most likely causes for this code to be set are

  1. Ignition System-Related Part(s) Failed
  2. Poor Ckp Sensor Signal
  3. Incorrect Air/Fuel Ratio
  4. Low Compression Pressure
  5. Timing Belt Jumped Or Teeth Broken
  6. Egr System Failed
  7. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 22: CRANKSHAFT POSITION SENSOR. Check waveform of CKP sensor pulse width while keeping engine speed constant. The CKP sensor pulse width should be constant. If sensor is operating properly, go to next step. If sensor is not operating properly, check CKP sensor fault. See «DTC P0335: CRANKSHAFT POSITION SENSOR CIRCUIT MALFUNCTION»(ref-135484-S10183163982002022200000) .
  2. Set scan tool to the data reading mode for data list item 81: LONG-TERM FUEL COMPENSATION (TRIM) BANK 1. The fuel trim should be -12.5-12.5 when the load is 2500 RPM (during closed loop) after the engine is at operating temperature. If fuel trim is as specified, go to next step. If fuel trim is not as specified, check fuel trim fault. See «DTC P0171: SYSTEM TOO LEAN (BANK 1)»(ref-135484-S17343407542002022200000) , «DTC P0172: SYSTEM TOO RICH (BANK 1)»(ref-135484-S29652051942002022200000) , «P0174: SYSTEM TOO LEAN (BANK 2)»(ref-135484-S15017938362002122300000) or «P0175: SYSTEM TOO RICH (BANK 2)»(ref-135484-S07111554592002122700000) .
  3. Set scan tool to the data reading mode for data list item 82: SHORT-TERM FUEL COMPENSATION (TRIM) BANK 1. The fuel trim should be -12.5-12.5 when the load is 2500 RPM (during closed loop) after the engine is at operating temperature. If fuel trim is as specified, turn ignition switch to LOCK position, then go to next step. If fuel trim is not as specified, check fuel trim fault. See «DTC P0171: SYSTEM TOO LEAN (BANK 1)»(ref-135484-S17343407542002022200000) , «DTC P0172: SYSTEM TOO RICH (BANK 1)»(ref-135484-S29652051942002022200000) , «P0174: SYSTEM TOO LEAN (BANK 2)»(ref-135484-S15017938362002122300000) or «P0175: SYSTEM TOO RICH (BANK 2)»(ref-135484-S07111554592002122700000) .
  4. Remove the intake manifold. Remove each spark plug cable and spark plug. Connect spark plug to the spark plug cable. Ground the spark plug side electrode securely. Crank engine. When the engine is cranked, the spark plug should spark. If spark does not exist, turn ignition switch to LOCK position, then go to next step. If spark exists, turn ignition switch to LOCK position, then go to step 7 .
  5. Check spark plug gap. Gap standard value is .039-.043" (1.0-1.1 mm), limit is .051" (1.3 mm). If problem does not exist, go to next step. If problem exists, adjust gap or replace plug(s), then go to step 13 .
  6. Remove spark plug cables. Check spark plug cable boot and coating for cracks and measure spark plug cable resistance. Maximum resistance for each spark plug cable is 22 k/ohms. If problem does not exist, check ignition system. See appropriate SYSTEM & COMPONENT TESTING article. If problem exists, replace the faulty spark plug cable, then go to step 13 .
  7. Disconnect fuel injector harness connectors. Measure resistance across fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace suspect fuel injector(s), then go to step 13 .
  8. Check fuel injector harness connectors and intermediate connector B-48 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  10. Check for harness damage between fuel injectors and ECM harness connector C-51 or PCM harness connector C-52. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  11. Check the following items: Check for skipped timing belt teeth. Check for failed EGR valve. Check Compression. See MECHANICAL INSPECTION under PRELIMINARY INSPECTION & ADJUSTMENTS in «BASIC DIAGNOSTIC PROCEDURES»(ref-135483) article. If problem does not exist, go to next step. If problem exists, repair it, then go to step 13 .
  12. Ensure ignition is in LOCK position. Replace suspect fuel injector(s). Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0300 is output, replace ECM/PCM, then go to next step. If DTC P0300 is not output, this diagnosis is complete.
  13. Ensure ignition is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0300 is output, repeat diagnostic procedure. If DTC P0300 is not output, this diagnosis is complete.

Check condition is when engine speed is 440-6000 RPM, engine coolant temperature is more than 14°F (-10°C), intake air temperature is more than 14°F (-10°C), barometric pressure is more than 11 psi (76 kPa) and adaptive learning is complete for the vane which generates a Crankshaft Position (CKP) sensor signal. Engine must be running, excluding gear shifting, deceleration, sudden acceleration/deceleration and A/C compressor switching and the throttle deviation is -0.059-0.059 v/10 ms. Judgement criteria is when misfire has occurred more frequently than allowed during the last 200 revolutions when the catalyst temperature is more than 1742°F (950°C), or misfire has occurred in 20 or more of the last 1000 revolutions (corresponding to 1.5 times the limit of emission standard). Change in the angular acceleration of the crankshaft is used for misfire detection.

The most likely causes for this code to be set are

  1. Ignition Related Part(s) Failed
  2. Low Compression.
  3. Fuel Injector Failed
  4. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

Note. DO NOT adjust gap on platinum plugs. Cleaning of platinum plug may result in damage to platinum tip. If carbon deposits must be removed, use a plug cleaner and complete cleaning process within 20 seconds to protect electrode. DO NOT use a wire brush.

  1. Remove the intake manifold. Remove the spark plugs. Check spark plug gap. Gap standard value is .039-.043" (1.0-1.1 mm), limit is .051" (1.3 mm). If problem does not exist, go to next step. If problem exists, adjust gap or replace plug(s), then go to step 9 .
  2. Remove spark plug cables. Check spark plug cable boot and coating for cracks and measure spark plug cable resistance. Maximum resistance for each spark plug cable is 22 k/ohms. If the resistance is as specified, go to next step. If the resistance is not as specified, replace the faulty spark plug cable, then go to step 9 .
  3. Disconnect fuel injector harness connectors. Measure resistance across fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace suspect fuel injector(s), then go to step 9 .
  4. Check fuel injector harness connectors and intermediate connector B-48 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  5. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  6. Check for harness damage between fuel injectors and ECM harness connector C-51 or PCM harness connector C-52. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  7. Check compression. See MECHANICAL INSPECTION under PRELIMINARY INSPECTION & ADJUSTMENTS in «BASIC DIAGNOSTIC PROCEDURES»(ref-135483) article. If problem does not exist, go to next step. If problem exists, repair it, then go to step 9 .
  8. Ensure ignition is in LOCK position. Replace suspect fuel injector(s). Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0301-P0306 is output, replace ECM/PCM, then go to next step. If DTC P0301-P0306 is not output, this diagnosis is complete.
  9. Ensure ignition is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0301-P0306 is output, repeat diagnostic procedure. If DTC P0301-P0306 is not output, this diagnosis is complete.

Check condition is when 2 seconds or more have passed since the starting sequence was completed and engine speed is more than 2500 RPM. Judgment criteria is when KS output voltage (KS peak voltage in each 1/2 turn of the crankshaft) has not changed more than 0.06 volt in the last consecutive 200 periods.

The most likely causes for this code to be set are

  1. Open Or Short In KS Circuit Or Loose Connector
  2. KS Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Disconnect KS harness connector B35. Check KS harness connector B-35 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  2. Check resistance between ground and KS harness connector B-35 terminal No. 2. Resistance should be less than 2 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open or harness damage in circuit between KS harness connector B-35 terminal No. 2 and ground, then go to step 6 .
  3. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  4. Check for open or short to ground in circuit between KS harness connector B-35 terminal No. 1 and ECM harness connector C-62 terminal No. 91 or PCM harness connector C-59 terminal No. 90. If problem does not exist, go to next step. If problem exists, repair it, then go to step 6 .
  5. Ensure ignition is in LOCK position. Replace KS. Reinstall any removed components. Reconnect any disconnected connectors. Connect scan tool to DLC. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0325 is output, replace ECM/PCM, then go to next step. If DTC P0325 is not output, this diagnosis is complete.
  6. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 44: IGNITION COILS & IGNITION POWER TRANSISTOR. Check ignition timing with KS harness connector B-35 connected and disconnected. Ignition timing should retard more with KS harness connector B-35 disconnected than with KS harness connector B-35 connected. If ignition timing does not retard as specified, repeat diagnostic procedure. If ignition timing retards as specified, this diagnosis is complete.
  1. Check condition is when engine is being cranked. Judgment criteria is when CKP sensor output voltage has not changed (no pulse signal is input) for 2 seconds.
  2. Check condition is when engine is running. Judgement criteria is when normal signal identification pattern has not been input for cylinder identification from CKP sensor and Camshaft Position (CMP) sensor for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In Ckp Sensor Circuit Or Loose Connector
  2. CKP Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 22: CRANKSHAFT POSITION SENSOR. The tachometer and engine speed indicated on the scan tool should match. If sensor is not operating properly, turn the ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Connect lab scope pick-up at CKP sensor harness connector B-20 terminal No. 2, ECM harness connector C-58 terminal No. 43 or PCM harness connector C-55 terminal No. 45. Start the engine and run at idle. Compare waveform to normal pattern. (Scheme 44) If waveform is normal, turn ignition switch to LOCK position, then go to next step. If waveform is not normal, turn ignition switch to LOCK position, then go to step 5.
  3. Disconnect CKP sensor harness connector B-20. Check CKP sensor harness connector B-20 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  4. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 22: CRANKSHAFT POSITION SENSOR. The tachometer and engine speed indicated on the scan tool should match. If sensor is not operating properly, replace ECM/PCM, then go to step 21. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  5. Disconnect CKP sensor harness connector B-20. Check CKP sensor harness connector B-20 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  6. Turn ignition switch to ON position. Measure voltage between ground and CKP sensor harness connector B-20 terminal No. 2. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 11.
  7. Measure voltage between ground and ECM harness connector C-58 terminal No. 43 or PCM harness connector C-55 terminal No. 45 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 9.
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 21. If problem does not exist, repair open in circuit between CKP sensor harness connector B-20 terminal No. 2 and ECM harness connector C-58 terminal No. 43 or PCM harness connector C-55 terminal No. 45, then go to step 21.
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  10. Check for short to ground in circuit between CKP sensor harness connector B-20 terminal No. 2 and ECM harness connector C-58 terminal No. 43 or PCM harness connector C-55 terminal No. 45. If problem does not exist, replace ECM/PCM, then go to step 21. If problem exists, repair it, then go to step 21.
  11. Measure voltage between ground and CKP sensor harness connector B-20 terminal No. 3. Battery voltage should exist. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 13.
  12. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 21. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and CKP sensor harness connector B-20 terminal No. 3, then go to step 21.
  13. Check resistance between ground and CKP sensor harness connector B20 terminal No. 1. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 16.
  14. Check CKP sensor harness connector B-20 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  15. Check for open or harness damage in circuit between CKP sensor harness connector B-20 terminal No. 1 and ECM harness connector C-52 terminal No. 34 or PCM harness connector C-52 terminal No. 16. If problem does not exist, replace ECM/PCM, then go to step 21. If problem exists, repair it, then go to step 21.
  16. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  17. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  18. Check for harness damage between MFI relay harness connector A-18X terminal No. 4 and CKP sensor harness connector B-20 terminal No. 3. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  19. Check for harness damage between CKP sensor harness connector B-20 terminal No. 2 and ECM harness connector C-58 terminal No. 43 or PCM harness connector C-55 terminal No. 45. If problem does not exist, go to next step. If problem exists, repair it, then go to step 21.
  20. Visually check CKP sensor vane. If problem exists, repair it, then go to next step. If problem does not exist, replace CKP sensor, then go to next step.
  21. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0335 is output, repeat diagnostic procedure. If DTC P0335 is not output, this diagnosis is complete.
  1. Check condition is when engine speed is more than 50 RPM. Judgement criteria is when CMP sensor output voltage has not changed (no pulse signal is input) for 2 seconds.
  2. Check condition is when engine speed is more than 50 RPM. Judgement criteria is when normal cylinder identification signal pattern from CMP sensor and Crankshaft Position (CKP) sensor has not been input for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In CMP Sensor Circuit Or Loose Connector
  2. CMP Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Connect lab scope pick-up at test harness terminal No. 5, ECM harness connector C-58 terminal No. 50 or PCM harness connector C-55 terminal No. 56. Start the engine and run at idle. Compare waveform to a normal pattern. (Scheme 45) If waveform is normal, turn ignition switch to LOCK position, then go to next step. If waveform is not normal, turn ignition switch to LOCK position, then go to step 4.
  2. Disconnect distributor assembly harness connector B-22. Check distributor assembly harness connector B-22 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  3. Reconnect distributor assembly harness connector. Connect scan tool to DLC. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0340 is output, replace ECM/PCM, then go to step 20. If DTC P0340 is not output, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  4. Disconnect distributor assembly harness connector B-22. Check distributor assembly harness connector B-22 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  5. Turn ignition switch to ON position. Measure voltage between ground and distributor assembly harness connector terminal No. 5. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, go to step 10.
  6. Disconnect distributor assembly harness connector B-22. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-58 terminal No. 50 or PCM harness connector C-55 terminal No. 56 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 8.
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 20. If problem does not exist, repair open in circuit between distributor assembly harness connector B-22 terminal No. 5 and ECM harness connector C-58 terminal No. 50 or PCM harness connector C-55 terminal No. 56, then go to step 20.
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  9. Check for short to ground in circuit between distributor assembly harness connector B-22 terminal No. 5 and ECM harness connector C-58 terminal No. 50 or PCM harness connector C-55 terminal No. 56. If problem does not exist, replace ECM/PCM, then go to step 20. If problem exists, repair it, then go to step 20.
  10. Measure voltage between ground and distributor assembly harness connector B-22 terminal No. 6. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 12.
  11. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 20. If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and distributor assembly harness connector B-22 terminal No. 6, then go to step 20.
  12. Check resistance between ground and distributor assembly harness connector B-22 terminal No. 7. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 15.
  13. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  14. Check for open circuit or harness damage between distributor assembly harness connector B-22 terminal No. 7 and ECM harness connector C-51 terminal No. 34 or PCM harness connector C-52 terminal 16. If problem does not exist, replace ECM/PCM, then go to step 20. If problem exists, repair it, then go to step 20.
  15. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  16. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  17. Check for harness damage between MFI relay harness connector A-18X terminal No. 4 and distributor assembly harness connector B-22 terminal No. 6. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  18. Check for harness damage between distributor assembly harness connector B-22 terminal No. 5 and ECM harness connector C-58 terminal No. 50 or PCM harness connector C-55 terminal No. 56. If problem does not exist, go to next step. If problem exists, repair it, then go to step 20.
  19. Visually check CMP sensor vane. If problem exists, repair it, then go to next step. If problem does not exist, replace CMP sensor, then go to next step.
  20. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0340 is output, repeat diagnostic procedure. If DTC P0340 is not output, this diagnosis is complete.

Check condition is when at least 20 seconds have passed since the last monitor was complete, engine coolant temperature is more than 169°F (76°C), engine speed is 910-1650 RPM (A/T) or 1000-1650 RPM (M/T), intake air temperature is more than 32°F (0°C), barometric pressure is more than 11 psi (76 kPa), vehicle speed is 18.7 MPH or more (A/T) or 0.9 MPH or more (M/T), and at least 90 seconds have passed since Manifold Differential Pressure (MDP) sensor output voltage fluctuated 1.5 volts or more. The throttle valve must be closed, volumetric efficiency is less than 28 percent (A/T) or less than 18 percent (M/T), and 20 seconds have elapsed from the start of the previous monitoring. Monitoring time is 2 seconds by 3 times. Judgement criteria is when intake manifold pressure fluctuations width is less than 0.37 psi (2.6 kPa) when the EGR solenoid is turned on.

The most likely causes for this code to be set are

  1. Open Or Short In EGR Solenoid Circuit Or Loose Connector
  2. EGR Valve Does Not Open
  3. EGR Control Vacuum Is Too Low
  4. EGR Solenoid Failed
  5. MDP Sensor Failed
  6. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Check EGR system. See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in appropriate SYSTEM & COMPONENT TESTING article. If problem does not exist, go to next step. If problem exists, repair it, then go to step 3 .
  2. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 95: MANIFOLD DIFFERENTIAL PRESSURE SENSOR. Warm up the engine to normal operating temperature of 176-205°F (80-96°C). With engine idling, pressure should read 9.0-11.0 psi (62-76 kPa). If sensor is operating properly, turn ignition switch to LOCK position, clean EGR valve and EGR passage, then go to next step. If sensor is not operating properly, turn ignition switch to LOCK position, check MDP sensor circuit. See «DTC P1400: MANIFOLD DIFFERENTIAL PRESSURE SENSOR CIRCUIT MALFUNCTION»(ref-135484-S25464943902002022200000) .
  3. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EGR monitor pattern. See «EXHAUST GAS RECIRCULATION MONITOR»(ref-135484-S32355179932002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0401 is output, repeat diagnostic procedure. If DTC P0401 is not output, this diagnosis is complete.
  1. Check condition is when engine is being cranked and battery positive voltage is 10-16 volts. Judgment criteria is when the EGR solenoid coil surge voltage (battery positive voltage plus 2 volts) is not detected for 0.2 second. Only one monitor is performed during one drive cycle.
  2. Check condition is when battery positive voltage is 10-16 volts, on duty cycle of the EGR solenoid is 10-90 percent, on duty cycle of the evaporative emission purge solenoid is zero percent, evaporative emission ventilation solenoid is off and more than one second has elapsed after the conditions have been met. Judgment criteria is when the EGR solenoid coil surge voltage (battery positive voltage plus 2 volts) is not detected for one second.

The most likely causes for this code to be set are

  1. Open Or Short In EGR Solenoid Circuit Or Loose Connector
  2. EGR Solenoid Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the actuator test mode for item 10: EGR SOLENOID. EGR solenoid should make a clicking sound and vibrate when actuated. If EGR solenoid is not operating properly, exit actuator test, turn ignition switch to LOCK position, then go to next step. If EGR solenoid is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect EGR solenoid harness connector B-31. Check EGR solenoid harness connector B-31 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  3. Measure resistance across EGR solenoid terminals (component side). Resistance should be 29-35 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace EGR solenoid, then go to step 12 .
  4. Turn ignition switch to ON position. Measure voltage between ground and EGR solenoid harness connector B31 terminal No. 1. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 6 .
  5. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and EGR solenoid harness connector B-31 terminal No. 1, then go to step 12 .
  6. Reconnect EGR solenoid harness connector B-31. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 6 or PCM harness connector C-52 terminal No. 6 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 9 .
  7. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  8. Check for open or short to ground in circuit between EGR solenoid harness connector B-31 terminal No. 2 and ECM harness connector C-51 terminal No. 6 or PCM harness connector C-52 terminal No. 6. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  10. Check for harness damage between MFI relay harness connector A-18X terminal No. 1 and EGR solenoid harness connector B-31 terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  11. Check for harness damage between EGR solenoid harness connector B-31 terminal No. 2 and ECM harness connector C-51 terminal No. 6 or PCM harness connector C-52 terminal No. 6. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0403 is output, repeat diagnostic procedure. If DTC P0403 is not output, this diagnosis is complete.

Check condition is when engine speed is less than 3000 RPM, Volume Airflow (VAF) sensor output frequency is 69-169 Hz, intake air temperature is more than 14°F (-10°C), barometric pressure is more than 11 psi (76 kPa), the throttle valve is open, vehicle is under closed loop air/fuel ratio control and vehicle speed is 0.93 MPH or more. Monitoring time is 12 seconds by 7 times, short-term fuel trim is more than -30 percent and less than 25 percent, and the cumulative VAF sensor output frequency is more than 4000 Hz. Judgment criteria is when the rear HO2S signal frequency divided by front HO2S signal frequency equals 0.8 or more.

The most likely causes for this code to be set are

  1. Catalytic Converter Deteriorated
  2. HO2S Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Check exhaust system for leaks. If problem does not exist, turn ignition switch to LOCK position, then go to next step. If problem exists, repair it, then go to step 7 .
  2. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 69: HEATED OXYGEN SENSOR BANK 1, SENSOR 2 (right rear). When engine is revved, HO2S Bank 1, Sensor 2 (HO2S 1/2) output voltage should alternate between about zero volts and 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, check HO2S 1/2 circuit. See «DTC P0137: HEATED OXYGEN SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)»(ref-135484-S33716135282002022200000) , «DTC P0138: HEATED OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)»(ref-135484-S37260766902002120400000) and «DTC P0139: HEATED OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2)»(ref-135484-S05214200322002022200000) .
  3. Set scan tool to the data reading mode for data list item 39: HEATED OXYGEN SENSOR BANK 1, SENSOR 1 (right front). When engine is revved, front HO2S Bank 1 , sensor 1 (HO2S 1/1) output voltage should be 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, check right front HO2S 1/1 circuit. See «DTC P0132: HEATED OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 1)»(ref-135484-S05640480582002022200000) , «DTC P0133: HEATED OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1)»(ref-135484-S41353341142002022200000) and «DTC P0134: HEATED OXYGEN SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 1)»(ref-135484-S14288625392002022200000) .
  4. With scan tool set to the data reading mode for data list item 39: HEATED OXYGEN SENSOR BANK 1, SENSOR 1, hold engine speed at 2000 RPM. Scan tool reading should alternate between 0.4 volt or less and 0.6-1.0 volt at least 15 times within 10 seconds. If sensor is operating properly, go to next step. If sensor is not operating properly, replace HO2S 1/1, then go to step 7 .
  5. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135484-S22499384332002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0421 is output, replace right bank catalytic converter, then go to next step. If DTC P0421 is not output, this diagnosis is complete.
  6. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135484-S22499384332002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0421 output, replace ECM/PCM, then go to next step. If DTC P0421 is not output, this diagnosis is complete.
  7. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135484-S22499384332002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0421 is output, repeat diagnostic procedure. If DTC P0421 is not output, this diagnosis is complete.

Check condition is when engine speed is less than 3000 RPM, Volume Airflow (VAF) sensor output frequency is 69-169 Hz, intake air temperature is more than 14°F (-10°C) barometric pressure is more than 11 psi (76 kPa), the throttle valve is open, vehicle is under closed loop air/fuel ratio control and vehicle speed is 0.93 MPH or more. Monitoring time is 12 seconds by 7 times, short-term fuel trim is more than -30 percent and less than 25 percent, and the cumulative VAF sensor output frequency is more than 4000 Hz. Judgment criteria is when the rear HO2S signal frequency divided by front HO2S signal frequency equals 0.8 or more.

The most likely causes for this code to be set are

  1. Catalytic Converter Deteriorated
  2. HO2S Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Check exhaust system for leaks. If problem does not exist, turn ignition switch to LOCK position, then go to next step. If problem exists, repair it, then go to step 7 .
  2. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 59: HEATED OXYGEN SENSOR BANK 2, SENSOR 2 (left rear). When engine is revved, rear HO2S Bank 2, Sensor 2 (HO2S 2/2) output voltage should alternate between about zero volts and 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, check HO2S 2/2 circuit. See «DTC P0157: HEATED OXYGEN SENSOR CIRCUIT LOW VOLTAGE (BANK 2 SENSOR 2)»(ref-135484-S15071634322002022200000) , «DTC P0158: HEATED OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK 2 SENSOR 2)»(ref-135484-S22940339872002120400000) and «DTC P0159: HEATED OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 2 SENSOR 2)»(ref-135484-S42029536012002022200000) .
  3. Set scan tool to the data reading mode for data list item 11: HEATED OXYGEN SENSOR BANK 2, SENSOR 1 (left front). When engine is revved, front HO2S Bank 2, Sensor 1 (HO2S 2/1) output voltage should be 0.6-1.0 volt. If sensor is operating properly, go to next step. If sensor is not operating properly, check HO2S 2/1 circuit. See «DTC P0152: HEATED OXYGEN SENSOR CIRCUIT HIGH VOLTAGE (BANK 2 SENSOR 1)»(ref-135484-S18056632172002022200000) , «DTC P0153: HEATED OXYGEN SENSOR CIRCUIT SLOW RESPONSE (BANK 2 SENSOR 1)»(ref-135484-S06752617592002022200000) and «DTC P0154: HEATED OXYGEN SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 2 SENSOR 1)»(ref-135484-S42926851592002022200000) .
  4. With scan tool set to the data reading mode for data list item 11: HEATED OXYGEN SENSOR BANK 2, SENSOR 1, hold engine speed at 2000 RPM. Scan tool reading should alternate between 0.4 volt or less and 0.6-1.0 volt at least 15 times within 10 seconds. If sensor is operating properly, go to next step. If sensor is not operating properly, replace HO2S 2/1, then go to step 7 .
  5. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135484-S22499384332002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0431 is output, replace left bank catalytic converter, then go to next step. If DTC P0431 is not output, this diagnosis is complete.
  6. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135484-S22499384332002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0431 output, replace ECM/PCM, then go to next step. If DTC P0431 is not output, this diagnosis is complete.
  7. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135484-S22499384332002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0431 is output, repeat diagnostic procedure. If DTC P0431 is not output, this diagnosis is complete.

Check condition is when on duty cycle of the EVAP purge solenoid is zero percent and 20 seconds have elapsed from the time the duty cycle of the EVAP purge solenoid has turned to zero percent. Judgment criteria is when the pressure in the fuel tank is -0.29 psi (-2 kPa) or less.

The most likely causes for this code to be set are

  1. EVAP Purge Solenoid Failed
  2. EVAP VENT Solenoid Failed
  3. Clogged Hose Between EVAP Canister & EVAP VENT Solenoid
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Check for DTCs. If DTC P0441 is not output, turn ignition switch to ON position, then go to next step. If DTC P0441 is output, see «DTC P0451: EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE SENSOR RANGE/PERFORMANCE»(ref-135484-S08904611632002022200000) .
  2. Turn ignition switch to LOCK position. Remove the fuel cap. Turn ignition switch to ON position. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. Fuel tank differential pressure should be -0.94-094 in. Hg. (-3.3-3.3 kPa). If pressure is as specified, go to next step. If pressure is not as specified, see «DTC P0451: EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE SENSOR RANGE/PERFORMANCE»(ref-135484-S08904611632002022200000) .
  3. Set scan tool to the data reading mode for data list item actuator test mode for item 08: EVAPORATIVE EMISSION PURGE SOLENOID. EVAP purge solenoid should make a clicking sound and vibrate when actuated. If EVAP purge solenoid is operating properly, exit actuator test, turn ignition switch to LOCK position, then go to next step. If EVAP purge solenoid is not operating properly, replace EVAP purge solenoid, then go to step 5 .
  4. Turn ignition switch to ON position. Set scan tool to the actuator test mode for item 29: EVAPORATIVE EMISSION VENTILATION SOLENOID. EVAP VENT solenoid should make a clicking sound and vibrate when actuated. If EVAP VENT solenoid is operating properly, exit actuator test, turn ignition switch to LOCK position, then go to next step. If EVAP VENT solenoid is not operating properly, replace EVAP VENT solenoid, then go to next step.
  5. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP control system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0441 is output, repeat diagnostic procedure. If DTC P0441 is not output, this diagnosis is complete.

Scheme 44

Scheme 44
Scheme 44

DTC Set Conditions - 1

Note. Check conditions require remaining fuel amount to be 15-40 percent (fuel level sensor output voltage is 1.4-2.4 volts). The monitoring time depends on the fuel level and the temperature in the fuel tank (75-125 seconds).

  1. Test Conditions A: At Start Up Intake air temperature is 97°F (36°C) or less and engine coolant temperature 97°F (36°C) or less when the engine is started
  2. Test Conditions B: For Test To Run Fuel temperature is 97°F (36°C) or less, within 16 minutes after the engine is started, engine coolant temperature is more than 140°F (60°C), power steering pressure switch is OFF, barometric pressure is more than 11 psi (76 kPa), volumetric efficiency is 20-80 percent, Fuel Tank Differential Pressure (FTDP) sensor output voltage is 1-4 volts and vehicle speed is 12.4 mph or more.
  3. Test Conditions C: For Test To Stop Intake air temperature must be less than 41°F (5°C). When the EVAP purge solenoid and EVAP VENT solenoid are closed, the pressure rises more than 0.065 psi (451 kPa). The pressure fluctuation width is more than 0.094 psi (647 kPa). Judgment criteria is when internal pressure of the fuel tank has changed more than 0.122 psi (0.841 kPa) in 20 seconds after the tank and vapor line were closed.

DTC Set Conditions - 2

Note. Check conditions require remaining fuel amount to be 40-75 percent (fuel level sensor output voltage is 2.4-3.7 volts). The monitoring time depends on the fuel level and the temperature in the fuel tank (10-14 minutes).

  1. Test Conditions A: At Start Up Intake air temperature is 97°F (36°C) or less when the engine is started. The engine coolant temperature 97°F (36°C) or less when the engine is started.
  2. Test Conditions B: For Test To Run Fuel temperature is 97°F (36°C) or less. Barometric pressure is more than 11 psi (76 kPa). Volumetric efficiency is 20-80 percent. FTDP sensor output voltage is 1-4 volts.
  3. Test Conditions C: For Test To Stop Intake air temperature is less than 14°F (-10°C). Engine coolant temperature is less than 68°F (20°C). When the EVAP purge solenoid and EVAP VENT solenoid are closed, the pressure rises to more than 0.047 psi (324 kPa). Judgment criteria is when internal pressure of the fuel tank has changed more than 0.29 psi (2 kPa) in 128 seconds after the tank and vapor line were closed.

The most likely causes for this code to be set are

  1. Loose Fuel Cap
  2. Fuel Cap Relief Pressure Is Incorrect
  3. EVAP Canister Seat Is Faulty
  4. Fuel Tank, Purge Line Or Vapor Line Seal Failed
  5. EVAP VENT Solenoid Failed

To determine the cause of DTC P0442, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool set on the FTDP sensor (TANK PRES SNER 73). The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines the problem in the system. Prior to doing the performance test, several simple inspections are needed to exclude some possibilities of the symptom.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

Note. With this monitor, the ECM/PCM automatically increases the engine speed to 1600 RPM or more.

  1. Ensure fuel cap is securely tightened (tighten until 3 clicks are heard). Ensure transaxle is in Park (A/T) or Neutral (M/T). Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Using scan tool, select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. During monitor, keep accelerator pedal in idle position. If the engine speed does not reach 2000 RPM during the monitor test, adjustment of the speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW under IDLE SPEED & MIXTURE in «ON-VEHICLE ADJUSTMENTS»(ref-135481) article. Keep the engine speed and engine load within the specified range. When the monitor test starts, the IN PROGRESS item on scan tool will change from NO to YES. Note message displayed on scan tool. Turn the ignition switch to LOCK position. If EVAP LEAK MON. COMPLETED TEST PASSED was displayed on the scan tool, the EVAP system is working properly at this time. Explain to customer that an improperly tightened fuel cap can cause MIL to turn on, and return the vehicle. If EVAP LEAK MON. COMPLETED. TEST FAILED AND DTCS SET was displayed on the scan tool, a malfunction has been detected during the monitor test, go to next step. If EVAP LEAD MON. DISCONTINUED. RETEST AGAIN FROM THE FIRST is displayed on the scan tool, the monitor was discontinued for a certain reason (vehicle speed input from computer, engine speed and engine load deviating from specified range). Repeat this step.
  2. Remove the battery. Remove the air intake hose. Disconnect hose "C" from the EVAP purge solenoid side, and connect a hand vacuum pump to the nipple of the EVAP purge solenoid. Apply pressure on hand vacuum pump, and confirm that air is maintained. Disconnect the hand vacuum pump, and reconnect hose "C". If the EVAP purge solenoid is in good condition, go to next step. If the EVAP purge solenoid is not in good condition, replace the EVAP purge solenoid, then go to step 17.
  3. Using hand vacuum pump, check for leaks in the evaporator line from hose "A" to hose "E". If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), then go to step 17.
  4. Connect scan tool to DLC. Disconnect hose "G" from EVAP VENT solenoid side. Connect hand vacuum pump to the nipple of the EVAP VENT solenoid from which the hose has been disconnected. Turn ignition switch to ON position. Set scan tool to actuator test mode for item actuator test item 29: EVAPORATIVE EMISSION VENTILATION SOLENOID. When the EVAP VENT solenoid is operated, apply pressure on the hand vacuum pump and confirm that air is maintained. Turn ignition switch to LOCK position. Disconnect the hand vacuum pump, and reconnect hose "G". If the EVAP VENT solenoid is in good condition, go to next step. If the EVAP VENT solenoid is not in good condition, replace the EVAP VENT solenoid, then go to step 17.
  5. Remove module bracket mounting bolts. Disconnect hose "G" from EVAP VENT solenoid and plug the hose. Confirm EVAP system pressure pump is operating properly. Perform self-test as described in manufacturer's instructions. Connect EVAP system pressure pump to fuel filler neck. Pressure test system to determine if any leak exists in hoses "F"-"P". If hoses are not in good condition, replace the faulty hose(s), reconnect hose "G", then go to next step. If hoses are in good condition, reconnect hose "G", then go to step 16.
  6. Disconnect hose "I" from EVAP VENT canister and plug the hose. Pressure test system to determine if any leak exists in hoses "I"-"P". If hoses are in good condition, reconnect hose "I", then go to next step. If hoses are not in good condition, replace the faulty hose(s), reconnect hose "I", then go to step 9.
  7. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Using hand vacuum pump, check hoses "F"-"H" for leaks. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank, then go to step 17.
  8. Connect hand vacuum pump to vent nipple of the EVAP canister where hose "G" was removed from. Plug other 2 EVAP canister ports. Apply vacuum to EVAP canister and confirm that vacuum does not fluctuate. If EVAP canister is in good condition, go to step 17. If EVAP canister is not in good condition, replace EVAP canister, reinstall fuel tank, then go to step 17.
  9. Remove fuel filler neck assembly. Disconnect hose "J" from liquid separator, and then connect a hand vacuum pump to the hose. Disconnect hose "K" at the fuel tank side, and then plug the hose. Using hand vacuum pump, apply vacuum, and confirm that vacuum does not fluctuate. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel filler neck assembly, then go to step 17.
  10. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Using hand vacuum pump, check hoses "I", and "L"-"O" for leaks. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank and fuel filler assembly, then go to step 17.
  11. Remove check valve "A". Blow on check valve "A" in both directions. Check valve "A" should leak air only in direction shown in illustration. (Scheme 47) If check valve "A" is in good condition, reinstall check valve "A", then go to next step. If check valve "A" is not in good condition, replace check valve "A", install fuel tank and fuel filler neck assembly, then go to step 17.
  12. Remove check valve "B". Blow on check valve "B" in both directions. Check valve "B" should pass more air in one direction than the other as shown in illustration. see scheme 88 If check valve "B" is in good condition, reinstall check valve "B", then go to next step. If check valve "B" is not in good condition, replace check valve "B", install fuel tank and fuel filler neck, then go to step 17.
  13. Disconnect hose "P" and connect hand vacuum pump to hose "P". Using hand vacuum pump, apply vacuum and check for leaks in hose "P". If hose is in good condition, go to next step. If hose is not in good condition, replace hose, reinstall fuel tank and fuel filler neck assembly, then go to step 17.
  14. Visually check for cracks in the fuel filler neck assembly. If the fuel filler neck assembly is in good condition, go to next step. If the fuel filler neck assembly is not in good condition, replace the fuel filler neck assembly, reinstall the fuel tank, then go to step 17.
  15. Visually check for cracks and leaks in the fuel tank. Carefully check the fuel pump assembly and the inner pressure sensor installation section in the fuel tank. Connect EVAP system pressure pump to the leveling valve nipple. Plug the filler hose, feed pipe, return pipe and rollover valve nipple connected to the fuel tank. Apply pressure with the EVAP system pressure pump. In the pressurized state, check for a leak by applying soapy water to each section. If the fuel tank is in good condition, go to next step. If the fuel tank is not in good condition, replace the fuel tank, reinstall the fuel filler neck assembly, then go to step 17.
  16. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Ensure fuel cap is securely tightened (tighten until 3 clicks are heard). Ensure transaxle is in Park (A/T) or Neutral (M/T). Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Using scan tool, select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. During monitor, keep accelerator pedal in idle position. If the engine speed does not reach 2000 RPM during the monitor test, adjustment of the speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW under IDLE SPEED & MIXTURE in «ON-VEHICLE ADJUSTMENTS»(ref-135481) article. Keep the engine speed and engine load within the specified range. When the monitor test starts, the IN PROGRESS item on scan tool will change from NO to YES. Note message displayed on scan tool. Turn the ignition switch to LOCK position. If EVAP LEAK MON. COMPLETED TEST PASSED was displayed on the scan tool, the EVAP system is working properly at this time, go to next step. If EVAP LEAK MON. COMPLETED. TEST FAILED AND DTCS SET was displayed on the scan tool, a malfunction has been detected during the monitor test. Replace ECM/PCM, then go to next step. If EVAP LEAD MON. DISCONTINUED. RETEST AGAIN FROM THE FIRST is displayed on the scan tool, the monitor was discontinued for a certain reason (vehicle speed input from computer, engine speed and engine load deviating from specified range). Repeat diagnostic procedure.
  17. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP control system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0442 is output, repeat diagnostic procedure. If DTC P0442 is not output, this diagnosis is complete.

Scheme 45

Scheme 45
Scheme 45

Scheme 46

Scheme 46
Scheme 46
  1. Check condition is when battery voltage is 10-16 volts. Judgement criteria is when EVAP purge solenoid coil surge voltage (battery positive voltage plus 2 volts) is not detected for 0.2 second. Only one monitor during drive cycle.
  2. Check condition is when battery voltage is 10-16 volts, on duty cycle of the EVAP purge solenoid is 10-90 percent, on duty cycle of the EGR solenoid is zero percent and EVAP VENT solenoid is off. More than one second has elapsed after the above mentioned conditions have been met. Judgment criteria is when the EVAP purge solenoid coil surge voltage (battery positive voltage plus 2 volts) is not detected for one second.

The most likely causes for this code to be set are

  1. Open Or Short In EVAP Purge Solenoid Circuit Or Loose Connector
  2. EVAP Purge Solenoid Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the actuator test mode for item 08: EVAPORATIVE EMISSION PURGE SOLENOID. EVAP purge solenoid should make a clicking sound and vibrate when actuated. If EVAP purge solenoid is not operating properly, exit actuator test, turn ignition switch to LOCK position, then go to next step. If EVAP purge solenoid is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect EVAP purge solenoid harness connector B-33. Check EVAP purge solenoid harness connector B-33 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  3. Measure resistance across EVAP purge solenoid connector terminals (component side). Resistance should be 30-34 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace EVAP purge solenoid, then go to step 12 .
  4. Turn ignition switch to ON position. Measure voltage between ground and EVAP purge solenoid harness connector B-33 terminal No. 2. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 6 .
  5. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and EVAP purge solenoid harness connector B-33 terminal No. 2, then go to step 12 .
  6. Reconnect EVAP purge solenoid harness connector B-33. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 16 or PCM harness connector C-52 terminal No. 34 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 9 .
  7. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  8. Check for open or short to ground in circuit between EVAP purge solenoid harness connector B-33 terminal No. 1 and ECM harness connector C-51 terminal No. 16 or PCM harness connector C-52 terminal No. 34. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  10. Check for harness damage between MFI relay harness connector A-18X terminal No. 1 and EVAP purge solenoid harness connector B-33 terminal No. 2. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  11. Check for harness damage between EVAP purge solenoid harness connector B-33 terminal No. 1 and ECM harness connector C-51 terminal No. 16 or PCM harness connector C-52 terminal No. 34. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0443 is output, repeat diagnostic procedure. If DTC P0443 is not output, this diagnosis is complete.
  1. Check condition is when battery voltage is 10-16 volts. Judgement criteria is when EVAP VENT solenoid coil surge voltage (battery positive voltage plus 2 volts) is not detected for 0.2 second. Only one monitor during drive cycle.
  2. Check condition is when battery voltage is 10-16 volts, on duty cycle of the EVAP purge solenoid is 10-90 percent, on duty cycle of the EGR solenoid is zero percent and EVAP VENT solenoid is on. More than one second has elapsed after the above mentioned conditions have been met. Judgment criteria is when the EVAP VENT solenoid coil surge voltage (battery positive voltage plus 2 volts) is not detected for one second.

The most likely causes for this code to be set are

  1. Open Or Short In EVAP VENT Solenoid Circuit Or Loose Connector
  2. EVAP VENT Solenoid Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Set scan tool to the actuator test mode for item 29: EVAPORATIVE EMISSION VENTILATION SOLENOID. EVAP VENT solenoid should make a clicking sound and vibrate when actuated. If EVAP VENT solenoid is not operating properly, exit actuator test, turn ignition switch to LOCK position, then go to next step. If EVAP VENT solenoid is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect EVAP VENT solenoid harness connector D-10. Check EVAP VENT solenoid harness connector D-10 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  3. Measure resistance across EVAP VENT solenoid connector terminals (component side). Resistance should be 17-21 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace EVAP VENT solenoid, then go to step 12 .
  4. Turn ignition switch to ON position. Measure voltage between ground and EVAP VENT solenoid harness connector D-10 terminal No. 2. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 6 .
  5. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and EVAP VENT solenoid harness connector D-10 terminal No. 2, then go to step 12 .
  6. Reconnect EVAP VENT solenoid connector. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-51 terminal No. 35 or PCM harness connector C-52 terminal No. 35 by backprobing. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 9 .
  7. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  8. Check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, check for open or short to ground in circuit between EVAP VENT solenoid harness connector D-10 terminal No. 1 and ECM harness connector C-51 terminal No. 35 or PCM harness connector C-52 terminal No. 35. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  9. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  10. Check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, check for harness damage between MFI relay harness connector A-18X terminal No. 4 and EVAP VENT solenoid harness connector D-10 terminal No. 2. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  11. Check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, check for harness damage between EVAP VENT solenoid harness connector D-10 terminal No. 1 and ECM harness connector C-51 terminal No. 35 or PCM harness connector C-52 terminal No. 35. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0446 is output, repeat diagnostic procedure. If DTC P0446 is not output, this diagnosis is complete.

Note. If the number of the sudden pressure fluctuations does not reach twenty during one engine idling, the counter will be reset to zero. If the ignition switch is turned off, it will be also reset to zero. The conditions for deviating from idling are engine speed more than 2500 RPM, vehicle speed 9.3 MPH or more and volumetric efficiency is 55 percent or more.

Check condition is when idle switch is on, throttle valve is closed and vehicle speed is 0.93 MPH or less. Judgment criteria is when the event that the output voltage from the FTDP sensor changes by 0.2 volts or more (i.e. sudden pressure fluctuation) is counted at least twenty times during one engine idling, and then consecutively 8 times during normal driving conditions.

The most likely causes for this code to be set are

  1. Damaged Harness In The FTDP Sensor Circuit
  2. FTDP Sensor Failed
  3. ECM/PCM Failed

DTC P0451 can be set by faulty FTDP sensor, related circuit, or ECM/PCM. To check a system blockage, do a performance test using a mechanical vacuum gauge and scan tool set on the FTDP sensor (TANK PRS SNSR73.) The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines a problem in the system.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Disconnect hose "I" from the EVAP canister side, and plug the hose from which the pipe has been disconnected. Turn ignition switch to ON position. Remove the fuel cap. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. The fuel tank pressures should be -0.97-.97 in. Hg. (-3.3-3.3 kPa). Connect Miller EVAP System Pressure Pump (6872A) to the fuel filler neck, and apply pressure. The scan tool reading should increase. Turn the ignition switch to LOCK position. If the scan tool reading is not within the specified value, leave fuel cap off and go to next step. If the scan tool reading is within the specified value, reinstall fuel cap, then go to step 28 .
  2. Remove rear seat cushion. Remove the protector and locate intermediate connector D-16. Disconnect intermediate connector D-16. Using Special Tools (MB991658 and MB991709) or jumper wires, connect terminals No. 5, 6 and 8 on harness side of intermediate connector D-16 to respective terminals on component side of intermediate connector D-16. Turn ignition switch to ON position. Measure voltage between ground and intermediate connector D-16 terminal No. 5. Voltage should be 2-3 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6 .
  3. Measure voltage between ground and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92 by backprobing. Voltage should be 2-3 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 27 .
  4. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  5. Check for harness damage between intermediate connector D-16 terminal No. 5 and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  6. Measure voltage between ground and intermediate connector D-16 terminal No. 8. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 11 .
  7. Measure voltage between ground and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 9 .
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to step 27 . If problem exists, repair it, then go to step 28 .
  9. Disconnect intermediate connectors C-28, C-90 and D-16. Check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  10. Check for harness damage between intermediate connector D-16 terminal No. 8 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  11. Measure voltage between ground and intermediate connector D-16 terminal No. 6. Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 15 .
  12. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 28 .
  13. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  14. Check for harness damage between intermediate connector D-16 terminal No. 6 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to step 27 . If problem exists, repair it, then go to step 28 .
  15. Remove center exhaust pipe. Support fuel tank. Remove fuel tank band assembly. Tilt the fuel tank. Disconnect FTDP sensor harness connector D-18. Using Special Tool (MB991658) or jumper wires, connect terminals No. 1, 2 and 3 on harness side of FTDP sensor harness connector D-18 to respective terminals on component side of FTDP sensor connector D-18. Turn ignition switch to ON position. Measure voltage between ground and FTDP connector D-18 terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, go to step 18 .
  16. Disconnect intermediate connector D-16. Check intermediate connector D-16 and FTDP harness connector D-18 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  17. Check for harness damage between intermediate connector D-16 terminal No. 8 and FTDP sensor harness connector D-18 terminal No. 3. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  18. Measure voltage between ground and FTDP connector D-18 terminal No. 2. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, turn ignition switch to LOCK position, replace FTDP sensor, then go to step 28
  19. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 28 .
  20. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  21. Check for harness damage between FTDP sensor harness connector D-18 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  22. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 27 .
  23. Remove the fuel cap. Measure voltage between ground and FTDP sensor harness connector D-18 terminal No. 1. Voltage should be 2-3 volts. If voltage is as specified, go to next step. If voltage is not as specified, replace FTDP sensor, then go to step 28 .
  24. Measure voltage between ground and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92 by backprobing. Voltage should be 2-3 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 27 .
  25. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  26. Check for harness damage between FTDP harness connector D-18 terminal No. 1 and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  27. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Disconnect hose "I" from the evaporative emission canister side, and plug the hose from which the pipe has been disconnected. Turn ignition switch to ON position. Remove the fuel cap. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. The fuel tank pressures should be -0.97-.97 in. Hg. (-3.3-3.3 kPa). Connect EVAP system pressure pump to the fuel filler neck, and apply pressure. The scan tool reading should increase. Turn the ignition switch to LOCK position. If the scan tool reading is not within the specified value, replace ECM/PCM, then go to next step. If the scan tool reading is within the specified value, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  28. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0451 is output, repeat diagnostic procedure. If DTC P0451 is not output, this diagnosis is complete.

Check condition is when intake air temperature is more than 41°F (5°C), engine speed is 1600 RPM or more and volumetric efficiency is 20-80 percent. Judgment criteria is when the EVAP purge solenoid is off and the FTDP sensor output voltage remains 1.0 volt or less for 10 seconds.

The most likely causes for this code to be set are

  1. Open FTDP Sensor Circuit Or Loose Connector
  2. FTDP Sensor Failed
  3. ECM/PCM Failed

DTC P0452 can be set by faulty FTDP sensor, related circuit, or ECM/PCM. To check a system blockage, do a performance test using a mechanical vacuum gauge and scan tool set on the FTDP sensor (TANK PRS SNSR73.) The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines a problem in the system.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Disconnect hose "I" from the EVAP canister side, and plug the hose from which the pipe has been disconnected. Turn ignition switch to ON position. Remove the fuel cap. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. The fuel tank pressures should be -0.97-.97 in. Hg. (-3.3-3.3 kPa). Connect Miller EVAP System Pressure Pump (6872A) to the fuel filler neck, and apply pressure. The scan tool reading should increase. Turn the ignition switch to LOCK position. If the scan tool reading is not within the specified value, leave fuel cap off and go to next step. If the scan tool reading is within the specified value, reinstall fuel cap, then go to step 28 .
  2. Remove rear seat cushion. Remove the protector and locate intermediate connector D-16. Disconnect intermediate connector D-16. Using Special Tools (MB991658 and MB991709) or jumper wires, connect terminals No. 5, 6 and 8 on harness side of intermediate connector D-16 to respective terminals on component side of intermediate connector D-16. Turn ignition switch to ON position. Measure voltage between ground and intermediate connector D-16 terminal No. 5. Voltage should be 2-3 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6 .
  3. Measure voltage between ground and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92 by backprobing. Voltage should be 2-3 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 27 .
  4. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  5. Check for harness damage between intermediate connector D-16 terminal No. 5 and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  6. Measure voltage between ground and intermediate connector D-16 terminal No. 8. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 11 .
  7. Measure voltage between ground and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 9 .
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to step 27 . If problem exists, repair it, then go to step 28 28 .
  9. Disconnect intermediate connectors C-28, C-90 and D-16. Check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  10. Check for harness damage between intermediate connector D-16 terminal No. 8 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  11. Measure voltage between ground and intermediate connector D-16 terminal No. 6. Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 15 .
  12. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 28 .
  13. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  14. Check for harness damage between intermediate connector D-16 terminal No. 6 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to step 27 . If problem exists, repair it, then go to step 28 .
  15. Remove center exhaust pipe. Support fuel tank. Remove fuel tank band assembly. Tilt the fuel tank. Disconnect FTDP sensor harness connector D-18. Using Special Tool (MB991658) or jumper wires, connect terminals No. 1, 2 and 3 on harness side of FTDP sensor harness connector D-18 to respective terminals on component side of FTDP sensor connector D-18. Turn ignition switch to ON position. Measure voltage between ground and FTDP connector D-18 terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, go to step 18 .
  16. Disconnect intermediate connector D-16. Check intermediate connector D-16 and FTDP harness connector D-18 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  17. Check for harness damage between intermediate connector D-16 terminal No. 8 and FTDP sensor harness connector D-18 terminal No. 3. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  18. Measure voltage between ground and FTDP connector D-18 terminal No. 2. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, replace FTDP sensor, then go to step 28 .
  19. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 28 .
  20. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  21. Check for harness damage between FTDP sensor harness connector D-18 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  22. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 27 .
  23. Remove the fuel cap. Measure voltage between ground and FTDP sensor harness connector D-18 terminal No. 1. Voltage should be 2-3 volts. If voltage is as specified, go to next step. If voltage is not as specified, replace FTDP sensor, then go to step 28 .
  24. Measure voltage between ground and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92 by backprobing. Voltage should be 2-3 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 27 .
  25. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  26. Check for harness damage between FTDP harness connector D-18 terminal No. 1 and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  27. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Disconnect hose "I" from the evaporative emission canister side, and plug the hose from which the pipe has been disconnected. Turn ignition switch to ON position. Remove the fuel cap. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. The fuel tank pressures should be -0.97-.97 in. Hg. (-3.3-3.3 kPa). Connect Miller EVAP system pressure pump (6872A) to the fuel filler neck, and apply pressure. The scan tool reading should increase. Turn the ignition switch to LOCK position. If the scan tool reading is not within the specified value, replace ECM/PCM, then go to next step. If the scan tool reading is within the specified value, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  28. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0452 is output, repeat diagnostic procedure. If DTC P0452 is not output, this diagnosis is complete.

Check condition is when intake air temperature is more than 41°F (5°C), engine speed is 1600 RPM or more and volumetric efficiency is 20-80 percent. Judgment criteria is when the EVAP purge solenoid is activating at 100 percent ratio, the FTDP sensor output voltage remains 4 volts or more for 10 seconds.

The most likely causes for this code to be set are

  1. Open FTDP Sensor Circuit Or Loose Connector
  2. FTDP Sensor Failed
  3. ECM/PCM Failed

DTC P0453 can be set by faulty FTDP sensor, related circuit, or ECM/PCM. To check a system blockage, do a performance test using a mechanical vacuum gauge and scan tool set on the FTDP sensor (TANK PRS SNSR73.) The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines the problem in the system.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Disconnect hose "I" from the EVAP canister side, and plug the hose from which the pipe has been disconnected. Turn ignition switch to ON position. Remove the fuel cap. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. The fuel tank pressures should be -0.97-.97 in. Hg. (-3.3-3.3 kPa). Connect Miller EVAP System Pressure Pump (6872A) to the fuel filler neck, and apply pressure. The scan tool reading should increase. Turn the ignition switch to LOCK position. If the scan tool reading is not within the specified value, leave fuel cap off and go to next step. If the scan tool reading is within the specified value, reinstall fuel cap, then go to step 28 .
  2. Remove rear seat cushion. Remove the protector and locate intermediate connector D-16. Disconnect intermediate connector D-16. Using Special Tools (MB991658 and MB991709) or jumper wires, connect terminals No. 5, 6 and 8 on harness side of intermediate connector D-16 to respective terminals on component side of intermediate connector D-16. Turn ignition switch to ON position. Measure voltage between ground and intermediate connector D-16 terminal No. 5. Voltage should be 2-3 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6 .
  3. Measure voltage between ground and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92 by backprobing. Voltage should be 2-3 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 27 .
  4. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  5. Check for harness damage between intermediate connector D-16 terminal No. 5 and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  6. Measure voltage between ground and intermediate connector D-16 terminal No. 8. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 11 .
  7. Measure voltage between ground and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 9 .
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to step 27 . If problem exists, repair it, then go to step 28 .
  9. Disconnect intermediate connectors C-28, C-90 and D-16. Check intermediate connectors C-28, C-90 and D-16 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  10. Check for harness damage between intermediate connector D-16 terminal No. 8 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  11. Measure voltage between ground and intermediate connector D-16 terminal No. 6. Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 15 .
  12. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 28 .
  13. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  14. Check for harness damage between intermediate connector D-16 terminal No. 6 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to step 27 . If problem exists, repair it, then go to step 28 .
  15. Remove center exhaust pipe. Support fuel tank. Remove fuel tank band assembly. Tilt the fuel tank. Disconnect FTDP sensor harness connector D-18. Using Special Tool (MB991658) or jumper wires, connect terminals No. 1, 2 and 3 on harness side of FTDP sensor harness connector D-18 to respective terminals on component side of FTDP sensor connector D-18. Turn ignition switch to ON position. Measure voltage between ground and FTDP connector D-18 terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, go to step 28 .
  16. Disconnect intermediate connector D-16. Check intermediate connector D-16 and FTDP harness connector D-18 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  17. Check for harness damage between intermediate connector D-16 terminal No. 8 and FTDP sensor harness connector D-18 terminal No. 3. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  18. Measure voltage between ground and FTDP connector D-18 terminal No. 2. Voltage should be 4.8-5.2 volts. If voltage is not as specified, go to next step. If voltage is as specified, replace FTDP sensor, then go to step 28
  19. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 28 .
  20. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  21. Check for harness damage between FTDP sensor harness connector D-18 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  22. Measure voltage between ground and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57 by backprobing. Voltage should be 0.5 volt or less. If voltage is as specified, go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 27 .
  23. Remove the fuel cap. Measure voltage between ground and FTDP sensor harness connector D-18 terminal No. 1. Voltage should be 2-3 volts. If voltage is as specified, go to next step. If voltage is not as specified, replace FTDP sensor, then go to step 28 .
  24. Measure voltage between ground and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92 by backprobing. Voltage should be 2-3 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 27 .
  25. Disconnect intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59. Check intermediate connectors C-28, C-90 and D-16, and ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 28 .
  26. Check for harness damage between FTDP harness connector D-18 terminal No. 1 and ECM harness connector C-62 terminal No. 93 or PCM harness connector C-59 terminal No. 92. If problem does not exist, go to step 28 . If problem exists, repair it, then go to step 28 .
  27. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Disconnect hose "I" from the evaporative emission canister side, and plug the hose from which the pipe has been disconnected. Turn ignition switch to ON position. Remove the fuel cap. Set scan tool to the data reading mode for data list item 73: FUEL TANK DIFFERENTIAL PRESSURE SENSOR. The fuel tank pressures should be -0.97-.97 in. Hg. (-3.3-3.3 kPa). Connect EVAP system pressure pump to the fuel filler neck, and apply pressure. The scan tool reading should increase. Turn the ignition switch to LOCK position. If the scan tool reading is not within the specified value, replace ECM/PCM, then go to next step. If the scan tool reading is within the specified value, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  28. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0453 is output, repeat diagnostic procedure. If DTC P0453 is not output, this diagnosis is complete.

Note. Check conditions require remaining fuel amount to be 15-40 percent (fuel level sensor output voltage is 1.4-2.4 volts). The monitoring time depends on the fuel level and the temperature in the fuel tank (75-125 seconds).

  1. Test Conditions A: At Start Up Intake air temperature is 97°F (36°C) or less and engine coolant temperature 97°F (36°C) or less when the engine is started.
  2. Test Conditions B: For Test To Run Engine coolant temperature is 136°F (58°C) or more with fuel level of 15-40 percent or the engine coolant temperature 68°F (20°C) or more with fuel level of 40-80 percent, engine speed is 1600 RPM or more, barometric pressure is more than 76 kPa (11 psi), volumetric efficiency is 20-80 percent, the fuel temperature is 97°F (36°C) or less, and Fuel Tank Differential Pressure (FTDP) sensor output voltage 1-4 volts.
  3. Test Conditions C: For Test To Stop Intake air temperature must be less than 41°F (5°C). When the EVAP purge solenoid and EVAP VENT solenoid are closed, the pressure rises more than 0.065 psi (0.448 kPa) when the amount of fuel remaining is 15-40 percent or more than 0.047 psi (0.324 kPa) when the amount of fuel remaining is 40-85 percent. Judgment criteria is when internal pressure of the fuel tank has changed more than 0.29 psi (0.841 kPa) in 20 seconds after the tank and vapor line were closed.

The most likely causes for this code to be set are

  1. Loose Fuel Cap
  2. Fuel Cap Relief Pressure Is Incorrect
  3. Fuel Overflow Limiter Valve Failed
  4. Purge Line Or Vapor Line Is Clogged
  5. Fuel tank, purge line or vapor line seal Failed
  6. EVAP Purge solenoid Failed
  7. EVAP VENT solenoid Failed
  8. FTDP sensor Failed
  9. EVAP canister seal is faulty.
  10. EVAP canister is clogged.

To determine the cause of DTC P0455, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool set on the FTDP sensor (TANK PRES SNER 73). The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines a problem in the system. Prior to doing the performance test, several simple inspections are needed to exclude some possibilities of the symptom.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

Note. With this monitor, the ECM/PCM automatically increases the engine speed to 1600 RPM or more.

  1. Ensure fuel cap is securely tightened (tighten until 3 clicks are heard). Ensure transaxle is in Park (A/T) or Neutral (M/T). Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Using scan tool, select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. During monitor, keep accelerator pedal in idle position. If the engine speed does not reach 2000 RPM during the monitor test, adjustment of the speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW under IDLE SPEED & MIXTURE in «ON-VEHICLE ADJUSTMENTS»(ref-135481) article. Keep the engine speed and engine load within the specified range. When the monitor test starts, the IN PROGRESS item on scan tool will change from NO to YES. Note message displayed on scan tool. Turn the ignition switch to LOCK position. If EVAP LEAK MON. COMPLETED TEST PASSED was displayed on the scan tool, the EVAP system is working properly at this time. Explain to customer that an improperly tightened fuel cap can cause MIL to turn on, and return the vehicle. If EVAP LEAK MON. COMPLETED. TEST FAILED AND DTCS SET was displayed on the scan tool, a malfunction has been detected during the monitor test. Go to next step. If EVAP LEAD MON. DISCONTINUED. RETEST AGAIN FROM THE FIRST is displayed on the scan tool, the monitor was discontinued for a certain reason (vehicle speed input from computer, engine speed and engine load deviating from specified range). Repeat this step.
  2. Disconnect hoses "B" and "C" from the evaporative emission purge solenoid side, and connect the hand vacuum pump to the evaporative emission purge solenoid instead of hose "C". Turn the ignition switch to ON position. Set scan tool to actuator test mode item 08: EVAPORATIVE EMISSION PURGE SOLENOID. When the EVAP purge solenoid is operated, apply a pressure on the hand vacuum pump and confirm that air is blown from the other side nipple. Turn the ignition switch to LOCK position. Disconnect the hand vacuum pump, and connect hoses "B" and "C" to the EVAP purge solenoid. If the EVAP solenoid is in good condition, go to next step. If the EVAP solenoid is not in good condition, replace the EVAP purge solenoid, then go to step 26.
  3. Check for leaks and clogging in the evaporator line from hoses "A"-"E". If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), then go to step 26
  4. Disconnect hose "G" from the EVAP VENT solenoid side, and connect hand vacuum pump to the nipple of the EVAP VENT solenoid from which the hose has been disconnected. Turn ignition switch to ON position. Set scan tool to actuator test mode for item actuator test item 29: EVAPORATIVE EMISSION VENTILATION SOLENOID. When the EVAP VENT solenoid is operated, apply a pressure on the hand vacuum pump and confirm that air is maintained. Turn ignition switch to LOCK position. Disconnect the hand vacuum pump. If the EVAP VENT solenoid is in good condition, leave hose "G" disconnected and go to next step. If the EVAP VENT solenoid is not in good condition, reconnect hose "G" and replace the EVAP VENT solenoid, then go to step 26.
  5. Plug hose "G". Remove the fuel cap. Confirm EVAP system pressure pump is operating properly. Perform self-test as described in manufacturer's instructions. Connect EVAP system pressure pump to fuel filler neck. Apply a pressure on the EVAP system pressure pump, and confirm that air is maintained. If air is not maintained, reconnect hose "G", reinstall fuel cap, then go to next step. If air is maintained, reconnect hose "G", reinstall fuel cap, then go to step 16.
  6. Disconnect hose "I" from EVAP VENT canister and plug the hose. Pressure test system to determine if any leak exists in hoses "I"-"P". If hoses are not in good condition, replace the faulty hose(s), reconnect hose "I", then go to next step. If hoses are in good condition, reconnect hose "I", then go to step 9.
  7. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Using hand vacuum pump, check hoses "F"-"H" for leaks. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank, then go to step 26.
  8. Connect hand vacuum pump to vent nipple of the EVAP canister where hose "G" was removed from. Plug other 2 EVAP canister ports. Apply vacuum to EVAP canister and confirm that vacuum is maintained. If EVAP canister is in good condition, go to step 26. If EVAP canister is not in good condition, replace EVAP canister, reinstall fuel tank, then go to step 26.
  9. Disconnect hose "J" from liquid separator, and then connect a hand vacuum pump to the hose. Disconnect hose "K" at the fuel tank side, and then plug the hose. Using hand vacuum pump, apply vacuum, and confirm that vacuum is maintained. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank, then go to step 26.
  10. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Remove fuel filler neck assembly. Using hand vacuum pump, check hoses "I", and "L"-"O" for leaks. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank and fuel filler neck assembly, then go to step 26.
  11. Remove check valve "A". Blow on check valve "A" in both directions. Check valve "A" should leak air only in direction shown in illustration. (Scheme 47) If check valve "A" is in good condition, reinstall check valve "A", then go to next step. If check valve "A" is not in good condition, replace check valve "A", install fuel tank and fuel filler neck assembly, then go to step 26.
  12. Remove check valve "B". Blow on check valve "B" in both directions. Check valve "B" should pass more air in one direction than the other as shown in illustration. see scheme 88 If check valve "B" is in good condition, reinstall check valve "B", then go to next step. If check valve "B" is not in good condition, replace check valve "B", reinstall fuel tank and fuel filler neck assembly, then go to step 26.
  13. Disconnect hose "P" and connect hand vacuum pump to hose "P". Using hand vacuum pump, apply vacuum and check for leaks in hose "P". If hose is in good condition, reinstall hose, then go to next step. If hose is not in good condition, replace hose, reinstall fuel tank and fuel filler neck assembly, then go to step 26.
  14. Visually check for cracks and leaks in the fuel tank. Carefully check the fuel pump assembly and the inner pressure sensor installation section in the fuel tank. Connect EVAP system pressure pump to the leveling valve nipple. Plug the filler hose, feed pipe, return pipe and rollover valve nipple connected to the fuel tank. Apply pressure with the EVAP system pressure pump. In the pressurized state, check for a leak by applying soapy water to each section. If the fuel tank is in good condition, reinstall fuel tank, then go to next step. If the fuel tank is not in good condition, repair or replace the fuel tank, reinstall the fuel filler neck assembly, then go to step 26.
  15. Visually check for cracks in the fuel filler neck assembly. If the fuel filler neck assembly is in good condition, replace the fuel filler neck assembly, reinstall the fuel tank, then go to step 26. If the fuel filler neck assembly is not in good condition, replace the fuel filler neck assembly, reinstall the fuel tank, then go to step 26.
  16. Disconnect hose "I" from EVAP VENT canister and leave the hose unplugged. On the EVAP system pressure pump, set the pressure/hold valve to OPEN, and set the vent valve to CLOSED. Turn the pump timer to ON. You can reset the timer as required. These settings are listed under LEAK TEST in the pump instructions. Reset the timer as required. Air should pass through hose "I". If air passes through hose "1", reconnect hose "I", then go to next step. If air does not pass through hose "I", reconnect hose "I", then go to step 21.
  17. Disconnect hose "G" from EVAP VENT canister and leave the hose unplugged. On the EVAP system pressure pump, set the pressure/hold valve to OPEN, and set the vent valve to CLOSED. Turn the pump timer to ON. Reset the timer as required. Air should pass through hose "G". If air passes through hose "G", reconnect hose "G", then go to next step. If air does not pass through hose "G", go to step 19.
  18. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Ensure fuel cap is securely tightened (tighten until 3 clicks are heard). Ensure transaxle is in Park (A/T) or Neutral (M/T). Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Using scan tool, select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. During monitor, keep accelerator pedal in idle position. If the engine speed does not reach 2000 RPM during the monitor test, adjustment of the speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW under IDLE SPEED & MIXTURE in «ON-VEHICLE ADJUSTMENTS»(ref-135481) article. Keep the engine speed and engine load within the specified range. When the monitor test starts, the IN PROGRESS item on scan tool will change from NO to YES. Note message displayed on scan tool. Turn the ignition switch to LOCK position. If EVAP LEAK MON. COMPLETED TEST PASSED was displayed on the scan tool, the EVAP system is working properly at this time. Go to step 26. If EVAP LEAK MON. COMPLETED. TEST FAILED AND DTCS SET was displayed on the scan tool, a malfunction has been detected during the monitor test. Replace ECM/PCM, then go to step 26. If EVAP LEAD MON. DISCONTINUED. RETEST AGAIN FROM THE FIRST is displayed on the scan tool, the monitor was discontinued for a certain reason (vehicle speed input from computer, engine speed and engine load deviating from specified range). Repeat diagnostic procedure.
  19. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Using hand vacuum pump, check hoses "F"-"H" for clogs. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank, then go to step 26.
  20. Connect hand vacuum pump to vent nipple of the EVAP canister where hose "G" was removed from. Plug other 2 EVAP canister ports. Apply vacuum to EVAP canister. When each nipple is unplugged, air should pass through the unplugged nipple. If the EVAP canister is in good condition, reinstall fuel tank, then go to step 26. If EVAP canister is not in good condition, replace EVAP canister, reinstall fuel tank, then go to step 26.
  21. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Disconnect hose "J" at the liquid separator side, and then connect a hand vacuum pump to the hose. Unplug the hose "K" at the fuel tank side. Apply a pressure on the vacuum pump, air should pass through the hose "K". If the hoses are in good condition, go to next step. If the hoses are not in good condition, replace the faulty hose(s), reinstall the fuel tank, then go to step 26.
  22. Remove the fuel filler neck assembly. Using hand vacuum pump, check hoses "I" and "L"-"O" for clogs. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel filler neck assembly, then go to step 26.
  23. Remove check valve "A". Blow on check valve "A" in both directions. Check valve "A" should leak air only in direction shown in illustration. (Scheme 47) If check valve "A" is in good condition, reinstall check valve "A", then go to next step. If check valve "A" is not in good condition, replace check valve "A", install fuel filler neck assembly, then go to step 26.
  24. Remove check valve "B". Blow on check valve "B" in both directions. Check valve "B" should pass more air in one direction than the other as shown in illustration. see scheme 88 If check valve "B" is in good condition, reinstall check valve "B", then go to next step. If check valve "B" is not in good condition, replace check valve "B", reinstall fuel filler neck assembly, then go to step 26.
  25. Disconnect hose "J" at fuel tank. Using hand vacuum pump, check hose "J" for clogs. If hose is in good condition, go to next step. If hose is not in good condition, replace the faulty hose, reinstall fuel filler neck assembly, then go to next step.
  26. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0455 is output, repeat diagnostic procedure. If DTC P0455 is not output, this diagnosis is complete.

Note. The monitoring time depends on the fuel level and the temperature in the fuel tank (10-14 minutes).

  1. Test Conditions A: At Start Up The fuel level sensor output voltage is 2.4-3.7 volts when the engine starts (i.e., the amount of remaining fuel is 40-85 percent), intake air temperature is 91°F (33°C) or less and the engine coolant temperature is 91°F (33°C) or less.
  2. Test Conditions B: For Test To Run Barometric pressure is more than 11 psi (76 kPa), volumetric efficiency is 20-80 percent, fuel temperature is 91°F (33°C) or less, and Fuel Tank Differential Pressure (FTDP) sensor output voltage is 1-4 volts.
  3. Test Conditions C: For Test To Stop Engine coolant temperature is less than 68°F (20°C) and intake air temperature is less than 14°F (-10°C). When the EVAP purge solenoid and EVAP VENT solenoid are closed, the pressure rises more 0.047 psi (.324 kPa). Judgment criteria is when internal pressure of the fuel tank fluctuates 0.177-0.199 psi (1.22-1.37 kPa) or more in 10 seconds after the tank and vapor line were closed.

The most likely causes for this code to be set are

  1. Loose Fuel Cap
  2. Fuel Cap Relief Pressure Is Incorrect
  3. EVAP Canister Seal Is Faulty
  4. Fuel Tank, Purge Line Or Vapor Line Seal Failed
  5. EVAP VENT Solenoid Failed

To determine the cause of DTC P0456, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool set on the FTDP sensor (TANK PRES SNER 73.) The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines a problem in the system. Prior to doing the performance test, several simple inspections are needed to exclude some possibilities of the symptom.

CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

Note. With this monitor, the ECM/PCM automatically increases the engine speed to 1600 RPM or more.

  1. Ensure fuel cap is securely tightened (tighten until 3 clicks are heard). Ensure transaxle is in Park (A/T) or Neutral (M/T). Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Using scan tool, select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. During monitor, keep accelerator pedal in idle position. If the engine speed does not reach 2000 RPM during the monitor test, adjustment of the speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW under IDLE SPEED & MIXTURE in «ON-VEHICLE ADJUSTMENTS»(ref-135481) article. Keep the engine speed and engine load within the specified range. When the monitor test starts, the IN PROGRESS item on scan tool will change from NO to YES. Note message displayed on scan tool. Turn the ignition switch to LOCK position. If EVAP LEAK MON. COMPLETED TEST PASSED was displayed on the scan tool, the EVAP system is working properly at this time. Explain to customer that an improperly tightened fuel cap can cause MIL to turn on, and return the vehicle. If EVAP LEAK MON. COMPLETED. TEST FAILED AND DTCS SET was displayed on the scan tool, a malfunction has been detected during the monitor test. Go to next step. If EVAP LEAD MON. DISCONTINUED. RETEST AGAIN FROM THE FIRST is displayed on the scan tool, the monitor was discontinued for a certain reason (vehicle speed input from computer, engine speed and engine load deviating from specified range). Repeat this step.
  2. Remove the battery. Remove the air intake hose. Disconnect hose "C" from the EVAP purge solenoid side, and connect a hand vacuum pump to the nipple of the EVAP purge solenoid. Apply pressure on hand vacuum pump, and confirm that air is maintained. Disconnect the hand vacuum pump, and reconnect hose "C". If the EVAP purge solenoid is in good condition, go to next step. If the EVAP purge solenoid is not in good condition, replace the EVAP purge solenoid, then go to step 17.
  3. Using hand vacuum pump, check for leaks in the evaporator line from hose "A" to hose "E". If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), then go to step 17.
  4. Disconnect hose "G" from EVAP VENT solenoid side. Connect hand vacuum pump to the nipple of the EVAP VENT solenoid from which the hose has been disconnected. Turn ignition switch to ON position. Set scan tool to actuator test mode for item actuator test item 29: EVAPORATIVE EMISSION VENTILATION SOLENOID. When the EVAP VENT solenoid is operated, apply pressure on the hand vacuum pump and confirm that air is maintained. Turn ignition switch to LOCK position. Disconnect the hand vacuum pump, and reconnect hose "G". If the EVAP VENT solenoid is in good condition, go to next step. If the EVAP VENT solenoid is not in good condition, replace the EVAP VENT solenoid, then go to step 17.
  5. Remove module bracket mounting bolts. Disconnect hose "G" from EVAP VENT solenoid and plug the hose. Confirm EVAP system pressure pump is operating properly. Perform self-test as described in manufacturer's instructions. Connect EVAP system pressure pump to fuel filler neck. Pressure test system to determine if any leak exists in hoses "F"-"P". If hoses are not in good condition, replace the faulty hose(s), reconnect hose "G", then go to next step. If hoses are in good condition, reconnect hose "G", then go to step 16.
  6. Disconnect hose "I" from EVAP VENT canister and plug the hose. Pressure test system to determine if any leak exists in hoses "I"-"P". If hoses are in good condition, reconnect hose "I", then go to next step. If hoses are not in good condition, replace the faulty hose(s), reconnect hose "I", then go to step 9.
  7. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Using hand vacuum pump, check hoses "F"-"H" for leaks. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank, then go to step 17.
  8. Connect hand vacuum pump to vent nipple of the EVAP canister where hose "G" was removed from. Plug other 2 EVAP canister ports. Apply vacuum to EVAP canister and confirm that vacuum does not fluctuate. If EVAP canister is in good condition, reinstall fuel tank, then go to step 17. If EVAP canister is not in good condition, replace EVAP canister, reinstall fuel tank, then go to step 17.
  9. Remove fuel filler neck assembly. Disconnect hose "J" from liquid separator, and then connect a hand vacuum pump to the hose. Disconnect hose "K" at the fuel tank side, and then plug the hose. Using hand vacuum pump, apply vacuum, and confirm that vacuum does not fluctuate. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel filler neck assembly, then go to step 17.
  10. Remove fuel tank. See FUEL TANK under FUEL SYSTEMS in «REMOVAL, OVERHAUL & INSTALLATION»(ref-135497) article. Using hand vacuum pump, check hoses "I", and "L"-"O" for leaks. If hoses are in good condition, go to next step. If hoses are not in good condition, replace the faulty hose(s), reinstall fuel tank and fuel filler assembly, then go to step 17.
  11. Remove check valve "A". Blow on check valve "A" in both directions. Check valve "A" should leak air only in direction shown in illustration. (Scheme 47) If check valve "A" is in good condition, reinstall check valve "A", then go to next step. If check valve "A" is not in good condition, replace check valve "A", reinstall fuel tank and fuel filler assembly, then go to step 17.
  12. Remove check valve "B". Blow on check valve "B" in both directions. Check valve "B" should pass more air in one direction than the other as shown in illustration. see scheme 88 If check valve "B" is in good condition, reinstall check valve "B", then go to next step. If check valve "B" is not in good condition, replace check valve "B", reinstall fuel tank and fuel filler assembly, then go to step 17.
  13. Disconnect hose "P" and connect hand vacuum pump to hose "P". Using hand vacuum pump, apply vacuum and check for leaks in hose "P". If hose is in good condition, go to next step. If hose is not in good condition, replace hose, reinstall fuel tank and fuel filler neck assembly, then go to step then go to step 17.
  14. Visually check for cracks in the fuel filler neck assembly. If the fuel filler neck assembly is in good condition, go to next step. If the fuel filler neck assembly is not in good condition, replace the fuel filler neck assembly, reinstall the fuel tank, then go to step 17.
  15. Visually check for cracks and leaks in the fuel tank. Carefully check the fuel pump assembly and the inner pressure sensor installation section in the fuel tank. Connect EVAP system pressure pump to the leveling valve nipple. Plug the filler hose, feed pipe, return pipe and rollover valve nipple connected to the fuel tank. Apply pressure with the EVAP system pressure pump. In the pressurized state, check for a leak by applying soapy water to each section. If the fuel tank is in good condition, reinstall fuel tank and fuel filler assembly, then go to next step. If the fuel tank is not in good condition, replace the fuel tank, reinstall the fuel filler neck assembly, then go to step 17.
  16. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Ensure fuel cap is securely tightened (tighten until 3 clicks are heard). Ensure transaxle is in Park (A/T) or Neutral (M/T). Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Using scan tool, select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. During monitor, keep accelerator pedal in idle position. If the engine speed does not reach 2000 RPM during the monitor test, adjustment of the speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW under IDLE SPEED & MIXTURE in «ON-VEHICLE ADJUSTMENTS»(ref-135481) article. Keep the engine speed and engine load within the specified range. When the monitor test starts, the IN PROGRESS item on scan tool will change from NO to YES. Note message displayed on scan tool. Turn the ignition switch to LOCK position. If EVAP LEAK MON. COMPLETED TEST PASSED was displayed on the scan tool, the EVAP system is working properly at this time. Go to next step. If EVAP LEAK MON. COMPLETED. TEST FAILED AND DTCS SET was displayed on the scan tool, a malfunction has been detected during the monitor test. Replace ECM/PCM, then go to next step. If EVAP LEAD MON. DISCONTINUED. RETEST AGAIN FROM THE FIRST is displayed on the scan tool, the monitor was discontinued for a certain reason (vehicle speed input from computer, engine speed and engine load deviating from specified range). Repeat diagnostic procedure.
  17. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle EVAP control system leak monitor pattern. See «EVAPORATIVE EMISSION CONTROL SYSTEM LEAK MONITOR»(ref-135484-S17250566142002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0456 is output, repeat diagnostic procedure. If DTC P0456 is not output, this diagnosis is complete.

Check conditions and judgement criteria are when the fuel consumption calculated from the operation time of the injector amounts to 21.1 Qts. (20 L), but the change in amount of fuel in tank calculated from the fuel level sensor is 2.1 Qts. (2 L) or less.

The most likely causes for this code to be set are

  1. Open Or Shorted Fuel Level Unit Circuit, Or Loose Connector
  2. Fuel Level Unit Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Set scan tool to the data reading mode for data list item 4B: FUEL LEVEL SENSOR. When the fuel gauge is near FULL, voltage should be 100-3600 mV. When the fuel gauge is near EMPTY, voltage should be 2700-6200 mV. If voltage is not as specified, turn the ignition switch to LOCK position, then go to next step. If voltage is as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect fuel level sensor harness connector D-17. Check fuel level sensor harness connector D-17 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  3. Check resistance between ground and fuel level sensor harness connector D-17 terminal No. 1. Resistance should be less than 2 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open or harness damage in circuit between fuel level sensor harness connector D-17 terminal No. 1 and ground, then go to step 12 .
  4. Remove instrument cluster. For removal and installation procedures, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Disconnect combination meter (instrument cluster) harness connector C-41. Turn ignition switch to ON position. Measure voltage between ground and fuel level sensor harness connector D-17 terminal No. 2. Battery voltage should exist. If battery voltage does not exist, turn ignition switch to LOCK position, reconnect fuel level sensor harness connector D-17, then go to next step. If battery voltage exists, turn ignition switch to LOCK position, reconnect fuel level sensor harness connector D-17, then go to step 9 .
  5. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-62 terminal No. 97 or PCM harness connector C-55 terminal No. 60 by backprobing. When the fuel gauge is near EMPTY, voltage should be 2.7-6.2 volts. If voltage is not as specified, turn the ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 7 .
  6. Disconnect intermediate connectors C-28 and C-90, and ECM harness connector C-62 or PCM harness connector C-55. Check intermediate connectors C-28 and C-90, and ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, repair open or harness damage in circuit between fuel level sensor harness connector D-17 terminal No. 2 and ECM harness connector C-62 terminal No. 97 or PCM harness connector C-55 terminal No. 60, then go to step 12 .
  7. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12
  8. Check for short to ground in circuit between fuel level sensor harness connector D-17 terminal No. 2 and ECM harness connector C-62 terminal No. 97 or PCM harness connector C-55 terminal No. 60. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  9. Check fuel gauge unit operation. See FUEL GAUGE TESTS under COMPONENT TESTS in appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. If fuel gauge unit is operating properly, reconnect combination meter harness connector C-41, then go to next step. If fuel gauge unit is not operating properly, replace fuel gauge unit, reconnect combination meter harness connector C-41, then go to step 12 .
  10. Disconnect ECM harness connector C-62 or PCM harness connector C-55. Check ECM harness connector C-62 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12
  11. Check for harness damage between fuel level sensor harness connector D-17 terminal No. 2 and ECM harness connector C-62 terminal No. 97 or PCM harness connector C-55 terminal No. 60. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0461 is output, repeat diagnostic procedure. If DTC P0461 is not output, inspection procedure is complete.

Check condition is when 2 seconds have passed since engine starting sequence was completed. Engine speed is 2100-4000 RPM. Volumetric efficiency is 40-70 percent. Judgement criteria is when VSS output voltage has not changed (no pulse signal is input) for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In VSS Circuit Or Loose Connector
  2. VSS Failed
  3. ECM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 24: VEHICLE SPEED SENSOR. Drive vehicle at 25 MPH. Check that speedometer and scan tool display speed matches. If VSS is not operating properly, turn ignition switch to LOCK position, then go to next step. If VSS is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Check speedometer. If speedometer is functioning, turn ignition switch to LOCK position, then go to next step. If speedometer is not functioning, turn ignition switch to LOCK position, then go to step 8.
  3. Remove instrument cluster. For removal and installation procedures, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Disconnect combination meter harness connectors and auto-cruise control ECU harness connector C-20. Connect lab scope pick-up lead to ECM harness connector C-62 terminal No. 80 by backprobing. Start the engine and move or drive vehicle. Compare VSS waveform on lab scope to normal VSS waveform. see scheme 89 If VSS waveform is normal, turn ignition switch to LOCK position, then go to next step. If VSS waveform is not normal, turn ignition switch to LOCK position, then go to step 6.
  4. Disconnect ECM harness connector C-62. Check ECM harness connector C-62 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 17.
  5. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Set scan tool to the data reading mode for data list item 24: VEHICLE SPEED SENSOR. Drive vehicle at 25 MPH. Check that speedometer and scan tool display speed matches. If VSS is not operating properly, replace ECM, then go to step 17. If VSS is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  6. Disconnect VSS harness connector B-39. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector C-62 terminal No. 80 by backprobing. Voltage should be 4.8-5.2 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, replace ECM, then go to step 17.
  7. Disconnect ECM harness connector C-62 and VSS intermediate connector B-36. Check VSS harness connector C-39, ECM harness connector C-62 and intermediate connector C-36 and for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, repair open in circuit between VSS harness connector B-39 terminal No. 3 and ECM harness connector C-62 terminal No. 80, then go to step 17.
  8. Disconnect VSS harness connector B-39. Check VSS harness connector B-39 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 17.
  9. Turn ignition switch to ON position. Measure voltage between ground and VSS harness connector B-39 terminal No. 1. Battery voltage should exist. If battery voltage exists, turn ignition switch to LOCK position, then go to next step. If battery voltage does not exist, check fuse block connectors C-111 and C-112, and intermediate connectors B-36, C-28 and C-78 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, repair open or short to ground in circuit between ignition switch harness connector C-87 terminal No. 2 and VSS harness connector B-39 terminal No. 1, then go to step 17.
  10. Check resistance between ground and VSS harness connector B-39 terminal No. 2. Resistance should be less than 2 ohms. If resistance is as specified, go to next step. If resistance is not as specified, check intermediate connector B-36 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, repair open in circuit between VSS harness connector B-39 terminal No. 2 and ground, then go to step 17.
  11. Ensure VSS harness connector B-39 is disconnected. Disconnect combination meter harness connectors and auto-cruise control ECU harness connector C-20. Turn ignition switch to ON position. Measure voltage between ground and VSS harness connector B-39 terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, check intermediate connector B-36 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, repair short to ground in circuit between VSS harness connector B-39 terminal No. 3 and ECM harness connector C-62 terminal No. 80, then go to step 17.
  12. Remove VSS. Connect battery, resistor (3-10 ohms), and voltmeter to indicated terminals. see scheme 90 Spin VSS shaft. Ensure voltage pulses 4 times per shaft revolution. If voltage pulses as specified, reinstall VSS, then go to next step. If voltage does not pulse as specified, replace VSS, then go to step 17.
  13. Disconnect ECM harness connector C-62. Check ECM harness connector C-62 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 17.
  14. Check fuse block connectors C-111 and C-112, and intermediate connectors B-36, C-28 and C-78 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, check for harness damage between ignition switch harness connector C-87 terminal No. 2 and VSS harness connector B-39 terminal No. 1. If problem does not exist, go to next step. If problem exists, repair it, then go to step 17.
  15. Check VSS harness connector C-39 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, check for harness damage between ECM harness connector C-62 terminal No. 80 and VSS harness connector B-39 terminal No. 3. If problem does not exist, go to next step. If problem exists, repair it, then go to step 17.
  16. Check intermediate connector C-36 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 17. If problem does not exist, check for harness damage between VSS harness connector B-39 terminal No. 2 and ground. If problem does not exist, go to next step. If problem exists, repair it, then go to next step.
  17. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 24: VEHICLE SPEED SENSOR. Drive vehicle at 25 MPH. Check that speedometer and scan tool display speed matches. If VSS is not operating properly, repeat diagnostic procedure. If VSS is operating properly, inspection procedure is complete

Scheme 47

Scheme 47
Scheme 47

Check condition is when vehicle is under closed loop idle speed control, engine coolant temperature is more than approximately 171°F (77°C), battery positive voltage is more than 10 volts, power steering pressure switch is off, volumetric efficiency is less than 40 percent, barometric pressure is more than 11 psi (76 kPa), intake air temperature is more than 14°F (-10°C), 60 seconds have elapsed from the start of the previous monitoring and target IAC motor position is more than 100 steps. Judgement criteria is when actual idle speed is more than 100 RPM less than target idle speed for 12 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In IAC Motor Circuit Or Loose Connector
  2. IAC Motor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Using scan tool, check for DTCs. If only P0506 is present, go to next step. If any DTC other than P0506 is present, diagnose other DTCs first. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-135484-S06660038382002022200000) .
  2. Check throttle body for deposits. If problem does not exist, go to next step. If problem exists, clean or repair as necessary, then go to step 14 .
  3. Disconnect IAC motor harness connector B-34. Check IAC motor harness connector B-34 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  4. Measure resistance between IAC motor terminal No. 2 and either terminal No. 1 or 3 (component side). Measure resistance between IAC motor terminal No. 5 and either terminal No. 4 or 6 (component side). Resistance should be 28-33 ohms at 68°F (20°C). If each resistance is as specified, go to next step. If either resistance is not as specified, replace IAC motor, then go to step 14 .
  5. Turn ignition switch to ON position. Measure voltage between ground and IAC motor harness connector B-34 terminal No. 2. Measure voltage between ground and IAC motor harness connector B-34 terminal No. 5. Battery voltage should exist. If battery voltage does not exist at one or both terminals, turn ignition switch to LOCK position, then go to next step. If battery voltage exists at both terminals, turn ignition switch to LOCK position then go to step 7 .
  6. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 14 . If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and IAC motor harness connector B-34 terminals No. 2 and 5, then go to step 14 .
  7. Reconnect IAC motor harness connector B-34. While turning ignition switch from LOCK position to ON position, measure voltage between ground and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 14 by backprobing. Repeat procedure at ECM harness connector C-51 or PCM harness connector C-52 terminals No. 15, 28 and 29. When ignition switch is turned from LOCK position to ON position, voltage should be one volt or less for about 3 seconds, then change to battery voltage. If voltage at any terminal is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage at all terminals is as specified, turn ignition switch to LOCK position, then go to step 10 .
  8. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  9. Check for open or short to ground in circuit between IAC motor harness connector B-34 terminal No. 1 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 14. Check for open or short to ground in circuit between IAC motor harness connector B-34 terminal No. 3 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 28. Check for open or short to ground in circuit between IAC motor harness connector B-34 terminal No. 4 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 15. Check for open or short to ground in circuit between IAC motor harness connector terminal No. 6 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 29. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  10. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  11. Remove IAC motor. Check for IAC motor operation (vibration) when battery positive terminal is jumpered to IAC motor terminal No. 2 (component side) and battery negative terminal is jumpered to IAC motor terminals No. 1 and 3 (component side). Check for IAC motor operation (vibration) when battery positive terminal is jumpered to IAC motor terminal No. 5 (component side) and battery negative terminal is jumpered to IAC motor terminals No. 4 and 6 (component side). IAC motor should operate at voltage application to each listed terminal combination. If IAC motor performs as specified, reinstall IAC motor, then go to next step. If IAC motor does not perform as specified, replace IAC motor, then go to step 14 .
  12. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  13. Check for harness damage between IAC motor harness connector B-34 terminal No. 1 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 14. Check for harness damage between IAC motor harness connector B-34 terminal No. 3 and ECM harness connector C-51 PCM harness connector C-52 terminal No. 28. Check for harness damage between IAC motor harness connector B-34 terminal No. 4 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 15. Check for harness damage between IAC motor harness connector B-34 terminal No. 6 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 29. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0506 is output, repeat diagnostic procedure. If DTC P0506 is not output, this diagnosis is complete.

Check condition is when vehicle speed has reached 0.93 MPH or more at least once, vehicle is under closed loop idle speed control, engine coolant temperature is more than approximately 171°F (77°C), battery positive voltage is more than 10 volts, barometric pressure is more than 11 psi (76 kPa), intake air temperature is more than 14°F (-10°C), 60 seconds have elapsed from the start of the previous monitoring and target IAC motor position is more zero steps. Judgement criteria is when actual idle speed has continued to be more than target idle speed by 200 RPM for 12 seconds or more than 300 RPM for 12 seconds if air temperature during previous operation was more than 113°F (45°C).

The most likely causes for this code to be set are

  1. Open Or Short In IAC Motor Circuit Or Loose Connector
  2. IAC Motor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, check for DTCs. If only P0507 is present, turn ignition switch to LOCK position, then go to next step. If any DTC other than P0507 is present, diagnose other DTCs first. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-135484-S06660038382002022200000) .
  2. Start the engine and run at idle. Check for intake system vacuum leak. If problem does not exist, turn ignition switch to LOCK position, then go to next step. If problem exists, repair it, then go to step 14 .
  3. Disconnect IAC motor harness connector B-34. Check IAC motor harness connector B-34 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  4. Measure resistance between IAC motor terminal No. 2 and either terminal No. 1 or 3 (component side). Measure resistance between IAC motor terminal No. 5 and either terminal No. 4 or 6 (component side). Resistance should be 28-33 ohms at 68°F (20°C). If each resistance is as specified, go to next step. If either resistance is not as specified, replace IAC motor, then go to step 14 .
  5. Turn ignition switch to ON position. Measure voltage between ground and IAC motor harness connector B-34 terminal No. 2. Measure voltage between ground and IAC motor harness connector B-34 terminal No. 5. Battery voltage should exist. If battery voltage does not exist at one or both terminals, turn ignition switch to LOCK position, then go to next step. If battery voltage exists at both terminals, turn ignition switch to LOCK position then go to step 7 .
  6. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 14 . If problem does not exist, repair open or short to ground in circuit between MFI relay harness connector A-18X terminal No. 4 and IAC motor harness connector B-34 terminals No. 2 and 5, then go to step 14 .
  7. Reconnect IAC motor harness connector B-34. While turning ignition switch from LOCK position to ON position, measure voltage between ground and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 14 by backprobing. Repeat procedure at ECM harness connector C-51 or PCM harness connector C-52 terminals No. 15, 28 and 29. When ignition switch is turned from LOCK position to ON position, voltage should be one volt or less for about 3 seconds, then change to battery voltage. If voltage at any terminal is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage at all terminals is as specified, turn ignition switch to LOCK position, then go to step 10 .
  8. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  9. Check for open or short to ground in circuit between IAC motor harness connector B-34 terminal No. 1 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 14. Check for open or short to ground in circuit between IAC motor harness connector B-34 terminal No. 3 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 28. Check for open or short to ground in circuit between IAC motor harness connector B-34 terminal No. 4 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 15. Check for open or short to ground in circuit between IAC motor harness connector terminal No. 6 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 29. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  10. Disconnect ECM harness connector C-51 or PCM harness connector C-52. Check ECM harness connector C-51 or PCM harness connector C-52 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step . 14 .
  11. Remove IAC motor. Check for IAC motor operation (vibration) when battery positive terminal is jumpered to IAC motor terminal No. 2 (component side) and battery negative terminal is jumpered to IAC motor terminals No. 1 and 3 (component side). Check for IAC motor operation (vibration) when battery positive terminal is jumpered to IAC motor terminal No. 5 (component side) and battery negative terminal is jumpered to IAC motor terminals No. 4 and 6 (component side). IAC motor should operate at voltage application to each listed terminal combination. If IAC motor performs as specified, reinstall IAC motor, then go to next step. If IAC motor does not perform as specified, replace IAC motor, then go to step 14 .
  12. Remove MFI relay from engine compartment relay box. Check MFI relay harness connector A-18X for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  13. Check for harness damage between IAC motor harness connector B-34 terminal No. 1 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 14. Check for harness damage between IAC motor harness connector B-34 terminal No. 3 and ECM harness connector C-51 PCM harness connector C-52 terminal No. 28. Check for harness damage between IAC motor harness connector B-34 terminal No. 4 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 15. Check for harness damage between IAC motor harness connector B-34 terminal No. 6 and ECM harness connector C-51 or PCM harness connector C-52 terminal No. 29. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0507 is output, repeat diagnostic procedure. If DTC P0507 is not output, this diagnosis is complete.

Check condition is when engine coolant temperature is more than 86°F (30°C). Drive for 4 seconds or more with the vehicle speed 31 MPH or more. Stop the vehicle (vehicle speed is 0.93 MPH or less). Repeat drive and stop 10 times or more. Judgment criteria is when PSP continues to be on.

The most likely causes for this code to be set are

  1. Open Or Short In PSP Switch Circuit Or Loose Connector
  2. PSP Switch Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 27: POWER STEERING PRESSURE SWITCH. Observe scan tool display when steering wheel is stopped and when steering wheel is being turned. With engine at idle, scan tool should display OFF when steering wheel is stopped and ON when steering wheel is being turned. If scan tool does not display as specified, turn ignition switch to LOCK position, then go to next step. If scan tool displays as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Measure voltage between ground and PSP switch harness connector B-19 terminal No. 1 by backprobing. Start the engine and run at idle. With engine at idle and steering wheel stationary, battery voltage should exist. With engine at idle and steering wheel being turned, voltage should be one volt or less. If voltage is as specified, turn ignition switch to LOCK position, then go to next step. If voltage is not as specified, turn ignition switch to LOCK position, then go to step 5 .
  3. Disconnect PSP switch harness connector B-19. Check PSP switch harness connector B-19 for loose, damaged or corroded terminal. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  4. Reconnect PSP switch harness connector B-19. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 27: POWER STEERING PRESSURE SWITCH. Observe scan tool display when steering wheel is stopped and when steering wheel is being turned. With engine at idle, scan tool should display off when steering wheel is stopped and on when steering wheel is being turned. If scan tool does not display as specified, replace ECM/PCM, then go to step 14 . If scan tool displays as specified, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  5. Disconnect PSP switch harness connector B-19. Check PSP switch harness connector B-19 for loose, damaged or corroded terminal. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  6. Turn ignition switch to ON position. Check voltage between ground and PSP switch harness connector B-19 terminal No. 1. Battery voltage should exist. If battery voltage does not exist, go to next step. If battery voltage exists, turn ignition switch to LOCK position, then go to step 11 .
  7. Measure voltage between ground and ECM harness connector C-58 terminal No. 54 or PCM harness connector C-55 terminal No. 52 by backprobing. Battery voltage should exist. If battery voltage exists, turn ignition switch to LOCK position, then go to next step. If battery voltage does not exist, turn ignition switch to LOCK position, then go to step 9 .
  8. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 14 . If problem does not exist, repair open in circuit between PSP switch harness connector B-19 terminal No. 1 and ECM harness connector C-58 terminal No. 54 or PCM harness connector C-55 terminal No. 52, then go to step 14 .
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  10. Disconnect intermediate connector B-47. Check intermediate connector B-47 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 14 . If problem does not exist, check for short to ground in circuit between PSP switch harness connector B-19 and ECM harness connector C-58 terminal No. 54 or PCM harness connector C-55 terminal No. 52. If problem does not exist, replace ECM/PCM, then go to step 14 . If problem exists, repair it, then go to step 14 .
  11. Replace PSP switch. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle. Check for DTCs. If DTC P0551 is output, turn ignition switch to LOCK position, then go to next step. If DTC P0551 is not output, turn ignition switch to LOCK position, then go to step 14 .
  12. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 14 .
  13. Disconnect intermediate connector B-47. Check intermediate connector B-47 for loose, damaged or corroded terminals. If problem exists, repair it, then go to next step. If problem does not exist, check for harness damage between PSP switch harness connector B-19 terminal No. 1 and ECM harness connector C-58 terminal No. 54 or PCM harness connector C-55 terminal No. 52. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  14. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 27: POWER STEERING PRESSURE SWITCH. Observe scan tool display when steering wheel is stopped and when steering wheel is being turned. With engine at idle, scan tool should display OFF when steering wheel is stopped and ON when steering wheel is being turned. If scan tool does not display as specified, repeat diagnostic procedure. If scan tool displays as specified, this diagnosis is complete.
  1. Check condition is when 8 minutes or more have passed after starting the engine if the engine coolant temperature is less than 32°F (0°C) when starting. Engine coolant temperature is more than 113°F (45°C). Intake air temperature is more than 32°F (0°C) and volumetric efficiency is 30-45 percent. Judgment criteria is when MDP sensor output voltage has continued to be more than 4.6 volts, corresponding to an absolute pressure of 17 psi (118 kPa) or more for 2 seconds or MDP sensor output voltage has continued to be less than 0.1 volt, corresponding to an absolute pressure of 0.3 psi (2.4 kPa) or less for 2 seconds.
  2. Check condition is when 8 minutes or more have passed after starting the engine if the engine coolant temperature is less than 32°F (0°C) when starting. Intake air temperature is more than 32°F (0°C) and volumetric efficiency is less than 30 percent. Judgment criteria is when MDP sensor output voltage has continued to be more than 4.2 volts, corresponding to an absolute pressure of 16 psi (108 kPa) or more for 2 seconds .
  3. Check condition is when 8 minutes or more have passed after starting the engine if the engine coolant temperature is less than 32°F (0°C) when starting. Intake air temperature is more than 32°F (0°C) and volumetric efficiency is more than 70 percent. Judgment criteria is when MDP sensor output voltage has continued to be less than 1.8 volts, corresponding to an absolute pressure of 4.6 psi (46 kPa) or less for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In MDP Sensor Circuit Or Loose Connector
  2. MDP Sensor Failed
  3. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Start the engine and run at idle. Set scan tool to the data reading mode for data list item 95: MANIFOLD DIFFERENTIAL PRESSURE SENSOR. While engine is idling, pressure should be 9.0-11.0 psi (62-76 kPa). If sensor is not operating properly, turn ignition switch to LOCK position, then go to next step. If sensor is operating properly, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  2. Disconnect MDP sensor harness connector B-04. Check MDP sensor harness connector B-04 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  3. Turn ignition switch to ON position. Measure voltage between ground and MDP sensor harness connector B-04 terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 6 .
  4. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  5. Check for open or short to ground in circuit between MDP sensor harness connector B-04 terminal No. 3 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  6. Check resistance between ground and MDP sensor harness connector B-04 terminal No. 2. Resistance should be less than 2 ohms. If resistance is not as specified, go to next step. If resistance is as specified, go to step 9 .
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  8. Check for open or harness damage in circuit between MDP sensor harness connector B-04 terminal No. 2 and ECM harness connector C-58 terminal No. 49 or PCM harness connector C-55 terminal No. 57. If problem does not exist, replace ECM/PCM, then go to step 12 . If problem exists, repair it, then go to step 12 .
  9. Disconnect ECM harness connector C-62 or PCM harness connector C-59. Check ECM harness connector C-62 or PCM harness connector C-59 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 12 . If problem does not exist, go to next step.
  10. Check for harness damage between MDP sensor harness connector B-04 terminal No. 3 and ECM harness connector C-58 terminal No. 42 or PCM harness connector C-55 terminal No. 46. If problem does not exist, go to next step. If problem exists, repair it, then go to step 12 .
  11. Check for open, short to ground or harness damage between MDP sensor harness connector B-04 terminal No. 1 and ECM harness connector C-62 terminal No. 92 or PCM harness connector C-59 terminal No. 91. If problem exists, repair it, then go to next step. If problem does not exist, replace MDP sensor, then go to next step.
  12. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC 1400 is output, repeat diagnostic procedure. If DTC P1400 is not output, this diagnosis is complete.

Check condition is when engine speed is more than 50 RPM. Judgement criteria is when input voltage from generator FR terminal has continued to be approximately battery voltage for 20 seconds.

The most likely causes for this code to be set are

  1. Open In Generator FR Terminal Circuit
  2. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Start the engine and run at idle. Measure voltage between ground and intermediate connector B-13 terminal No. 3 by backprobing. While engine is warming up and radiator fan is off, observe voltage drops while performing the following: Turn headlight switch from OFF position to ON position. Turn rear defogger switch from OFF position to ON position. Turn stoplight switch from OFF position to ON position by pressing on brake pedal. If voltage drops as specified, turn ignition switch to LOCK position, then go to next step. If voltage does not drop as specified, turn ignition switch to LOCK position, then go to step 4 .
  2. Disconnect intermediate connector B-13. Check intermediate connector B-13 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  3. Reconnect intermediate connector B-13. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P1500 is output, replace ECM/PCM, then go to step 11 . If DTC P1500 is not output, it can be assumed that this malfunction is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135484-S19188728872002022200000) under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.
  4. Disconnect intermediate connector B-13. Check intermediate connector B-13 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  5. Disconnect generator harness connector B-45. Check generator harness connector B-45 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  6. Turn ignition switch to ON position. Measure voltage between ground and generator harness connector B-45 terminal No. 4. Voltage should be 4.8-5.2 volts. If voltage is not as specified, turn ignition switch to LOCK position, then go to next step. If voltage is as specified, turn ignition switch to LOCK position, then go to step 9 .
  7. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  8. Check for open or short to ground in circuit between generator harness connector B-45 terminal No. 4 and ECM harness connector C-58 terminal No. 52 or PCM harness connector C-55 terminal No. 54. If problem does not exist, replace ECM/PCM, then go to step 11 . If problem exists, repair it, then go to step 11 .
  9. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, go to next step. If problem exists, repair it, then go to step 11 .
  10. Check for harness damage between generator harness connector B-45 terminal No. 4 and ECM harness connector C-58 terminal No. 52 or PCM harness connector C-55 terminal No. 54. If problem exists, repair it, then go to next step. If problem does not exist, replace generator, then go to next step.
  11. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle other monitor pattern. See «OTHER MONITOR»(ref-135484-S33802843322002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P1500 is output, repeat diagnostic procedure. If DTC P1500 is not output, this diagnosis is complete.

Check condition is when starting sequence was completed and battery voltage is more than 10 volts. Judgement criteria is when battery backup line voltage has continued to be 6 volts or less for 2 seconds.

The most likely causes for this code to be set are

  1. Open Or Short In Battery Backup Line Or Loose Connector
  2. ECM/PCM Failed
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

  1. Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, clear DTCs. Start the engine and run at idle. Check for DTCs. If DTC 1603 is output, turn ignition switch to LOCK position, then go to next step. If DTC P1603 is not output, this diagnosis is complete.
  2. Measure voltage between ground and ECM harness connector C-58 terminal No. 60 or PCM harness connector C-55 terminal No. 66 by backprobing. Battery voltage should exist. If battery voltage does not exist, go to next step. If battery voltage exists, go to step 5 .
  3. Disconnect ECM harness connector C-58 or PCM harness connector C-55. Measure voltage between ground and ECM harness connector C-58 terminal No. 60 or PCM harness connector C-55 terminal No. 66. Battery voltage should exist. If battery voltage exists, go to next step. If battery voltage does not exist, check intermediate connector C-07 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 6 . If problem does not exist, repair open or short to ground between battery and ECM harness connector C-58 terminal No. 60 or PCM harness connector C-55 terminal No. 66, then go to step 6 .
  4. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 6 . If problem does not exist, check intermediate connector C-07 for loose, damaged or corroded terminals. If problem exists, repair it, then go to step 6 . If problem does not exist, repair open or short to ground between battery and ECM harness connector C-58 terminal No. 60 or PCM harness connector C-55 terminal No. 66, then go to step 6 .
  5. Check ECM harness connector C-58 or PCM harness connector C-55 for loose, damaged or corroded terminals. If problem does not exist, replace ECM/PCM, then go to next step. If problem exists, repair it, then go to next step.
  6. Ensure ignition switch is in LOCK position. Reinstall any removed components. Reconnect any disconnected connectors. Using scan tool, clear DTCs. Turn ignition switch to ON position. Check for DTCs. If DTC P1603 is present, repeat diagnostic procedure. If DTC P1603 is not present, this diagnosis is complete.

Check condition is when Ignition switch is in ON position. Judgement criteria is when communication error between ECM/PCM and immobilizer ECU continues for 2 seconds or more.

The most likely causes for this code to be set are

  1. Harness Or Connector Malfunction
  2. Immobilizer ECU Malfunction
  3. ECM/PCM Malfunction
CAUTIONTo prevent damage to scan tool, always turn ignition switch to LOCK position before connecting or disconnecting scan tool.

Note. If ECM/PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

Turn ignition switch to LOCK position. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, check for immobilizer system DTCs (DTC 11 or 12). If immobilizer system DTC is present, diagnose immobilizer system concern. See IMMOBILIZER SYSTEMS - ECLIPSE article in ACCESSORIES & EQUIPMENT. If no immobilizer system DTCs are present, check for MFI DTC's. If DTC P1610 is output, replace ECM/PCM. If DTC P1610 is not output, this diagnosis is complete.

More articles — Engine Controls - Self-Diagnostics - 3.0L