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Home/Mitsubishi/Montero/Mitsubishi Montero III (1999-2006)/Repair manual/Testing & Diagnostics/Engine Controls - Self-Diagnostics: Diagnosis
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Engine Controls - Self-Diagnostics: Diagnosis Mitsubishi Montero III

Testing & Diagnostics 8 illustrations ~43489 words

SYSTEM DIAGNOSIS

CAUTIONIf radio has anti-theft feature, obtain radio anti-theft code before disconnecting battery. If Powertrain Control Module (PCM) is replaced, the immobilizer ECU should be replaced with it. PCM has specific individual information that must be registered in immobilizer ECU.

Note. Multiport Fuel Injection (MFI) system is controlled by a PCM. PCM diagnostic memory is retained by direct power supply from battery. Memory is not erased by turning off ignition, but it will be erased if battery or PCM is disconnected.

PCM includes On Board Diagnostics II (OBD-II) software designed to monitor emissions control system over the life of the vehicle. On OBD-II, the MIL will illuminate only for emissions 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 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 emissions system related. DTCs may be retrieved using the manufacturer's MUT-II Scan Tool (MB991502), or a compatible generic scan tool. See ENTERING ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.

PCM monitors several different engine control system circuits. If an abnormal input signal occurs, the 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 that cause of failure is necessarily within 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, PCM will enter fail-safe function (limp home mode). In fail-safe mode, PCM will substitute default values for the faulty component or system.

Each circuit or system monitored by PCM has particular engine and driving conditions that must be met before PCM will monitor it. These conditions are the code set criteria. 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 PCM monitors and runs tests on various inputs, outputs and system functions. There are 6 monitors. One monitor (Other Monitor) passively monitors for opens, 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. A system related Diagnostic Trouble Code (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. If vehicle is normal, readiness test status will complete by carrying out OBD-II drive cycle once. MUT-II scan tool will then read COMPLETE. Generic scan tool will read READY. If 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, PCM can be checked for DTCs.

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-135490-S07405084492002022200000) . Locate OBD-II Data Link Connector (OBD-II DLC) under instrument panel, near steering column.
  2. Turn ignition switch to OFF 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-135490-S24068601682002022200000) . If scan tool will not communicate with PCM, diagnose communication concern. See «SCAN TOOL WILL NOT COMMUNICATE»(ref-135490-S34379088062002022200000) under DIAGNOSTIC CIRCUIT CHECK. Turn ignition switch to OFF position before disconnecting scan tool.

CLEARING DIAGNOSTIC TROUBLE CODES

CAUTIONIf vehicle has anti-theft radio, 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.
CAUTIONAll data will be lost when DTCs are cleared. Record data that may be needed later, such as freeze frame data, before erasing DTCs.

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 PCM for a few minutes. Reconnect negative battery cable. Start and warm up engine. Run vehicle through appropriate drive cycle(s). Check for DTCs to confirm repair.

DTCs will be automatically erased by PCM under certain conditions

  1. If non-emission related fault does not reoccur within 51 engine starts.
  2. If emission related fault, except misfire and fuel system lean/rich, does not reoccur in 40 drives.
  3. If misfire or fuel system lean/rich fault does not reoccur in 80 drives.

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.

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 recorder function of scan tool. The following additional checks may assist in identifying a possible intermittent problem

  1. Check all pertinent Technical Service Bulletins (TSBs).
  2. Visually inspect related wiring connectors for broken, bent, pushed out or corroded terminals.
  3. Visually inspect related wiring 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.

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
P0106 (4)Barometric Pressure Circuit Range/Performance Problem
P0107Barometric Pressure Circuit Low Input
P0108Barometric Pressure Circuit High Input
P0111Intake Air Temperature Circuit Range/Performance Problem
P0112Intake Air Temperature Circuit Low Input
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
P0125 (2)Insufficient Coolant Temperature For Closed Loop Fuel Control
P0128Coolant Thermostat Malfunction
P0132Right Front HO2S Circuit High Voltage (Bank 1 Sensor 1)
P0133Right Front HO2S Circuit Slow Response (Bank 1 Sensor 1)
P0134 (4)Right Front HO2S Circuit No Activity Detected (Bank 1 Sensor 1)
P0135Right Front HO2S Heater Circuit Malfunction (Bank 1 Sensor 1)
P0137Right Rear HO2S Circuit Low Voltage (Bank 1 Sensor 2)
P0138Right Rear HO2S Circuit High Voltage (Bank 1 Sensor 2)
P0139Right Rear HO2S Circuit Slow Response (Bank 1 Sensor 2)
P0141Right Rear HO2S Heater Circuit Malfunction (Bank 1 Sensor 2)
P0152Left Front HO2S Circuit High Voltage (Bank 2 Sensor 1)
P0153Left Front HO2S Circuit Slow Response (Bank 2 Sensor 1)
P0154 (4)Left Front HO2S Circuit No Activity Detected (Bank 2 Sensor 1)
P0155Left Front HO2S Heater Circuit Malfunction (Bank 2 Sensor 1)
P0157Left Rear HO2S Circuit Low Voltage (Bank 2 Sensor 2)
P0158Left Rear HO2S Circuit High Voltage (Bank 2 Sensor 2)
P0159Left Rear HO2S Circuit Slow Response (Bank 2 Sensor 2)
P0161Left Rear HO2S Heater Circuit Malfunction (Bank 2 Sensor 2)
P0171Right Bank System Too Lean (Bank 1)
P0172Right Bank System Too Rich (Bank 1)
P0174Left Bank System Too Lean (Bank 2)
P0175Left Bank System Too Rich (Bank 2)
P0181Fuel Temperature Sensor Circuit Range/Performance Problem
P0182Fuel Temperature Sensor Circuit Low Input
P0183Fuel Temperature Sensor Circuit High Input
P0201Fuel Injector No. 1 Circuit Malfunction
P0202Fuel Injector No. 2 Circuit Malfunction
P0203Fuel Injector No. 3 Circuit Malfunction
P0204Fuel Injector No. 4 Circuit Malfunction
P0205Fuel Injector No. 5 Circuit Malfunction
P0206Fuel Injector No. 6 Circuit Malfunction
P0300Random/Multiple Cylinder Misfire Detected
P0301Cylinder No. 1 Misfire Detected
P0302Cylinder No. 2 Misfire Detected
P0303Cylinder No. 3 Misfire Detected
P0304Cylinder No. 4 Misfire Detected
P0305Cylinder No. 5 Misfire Detected
P0306Cylinder No. 6 Misfire Detected
P0325Knock Sensor Circuit Malfunction
P0335Crankshaft Position Sensor Circuit Malfunction
P0340Camshaft Position Sensor Circuit Malfunction
P0401EGR Insufficient Flow Detected
P0403EGR Solenoid Circuit Problem
P0421Right Warm Up Catalyst Efficiency Below Threshold (Bank 1)
P0431Left Warm Up Catalyst Efficiency Below Threshold (Bank 2)
P0441EVAP Emission Control System Incorrect Purge Flow
P0442EVAP Emission Control System Small Leak Detected (1mm)
P0443EVAP Emission Control System Purge Control Valve Circuit Problem
P0446EVAP Emission Control System Vent Control Malfunction
P0451EVAP Emission Control System Pressure Sensor Range/Performance Problem
P0452EVAP Emission Control System Pressure Sensor Low Input
P0453EVAP Emission Control System Pressure Sensor High Input
P0455EVAP Emission Control System Large Leak Detected
P0456EVAP Emission Control System Small Leak Detected (0.5mm)
P0461Fuel Level Sensor Circuit Range/Performance Problem
P0500 (3)Vehicle Speed Sensor Signal Malfunction
P0506Idle Control System RPM Lower Than Expected
P0507Idle Control System RPM Higher Than Expected
P0551Power Steering Pressure Sensor Circuit Range/Performance Problem
P0705 (3)Transmission Range Sensor Circuit Malfunction (PRNDL Input)
P0712 (3)Transmission Fluid Temperature Sensor Low Input
P0713 (3)Transmission Fluid Temperature Sensor High Input
P0715 (3)Input/Turbine Speed Sensor Circuit Malfunction
P0720 (3)Output Speed Sensor Circuit Malfunction
P0731 (3)Gear 1 Incorrect
P0732 (3)Gear 2 Incorrect
P0733 (3)Gear 3 Incorrect
P0734 (3)Gear 4 Incorrect
P0735 (3)Gear 5 Incorrect (5 A/T Only)
P0736 (3)Gear R Incorrect
P0741 (3)Torque Converter Clutch Circuit Performance Or Stuck Off
P0742 (3)Torque Converter Clutch Circuit Performance Or Stuck On
P0743 (3)Torque Converter Clutch Circuit Electrical Problem
P0753 (2) (3)Shift Solenoid "A" Malfunction
P0758 (2) (3)Shift Solenoid "B" Malfunction
P0763 (2) (3)Shift Solenoid "C" Malfunction
P0768 (2) (3)Shift Solenoid "D" Malfunction
P0773 (2) (3)Shift Solenoid "E" Malfunction (5 A/T Only)
P1400Manifold Differential Pressure Sensor Circuit Malfunction
P1603 (4)Battery Backup Circuit Malfunction
P1610Immobilizer Malfunction
P1751 (3)A/T Control Relay Malfunction
(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 on first trip fault is detected. (3) For diagnostic procedures, see appropriate DIAGNOSTICS article in AUTOMATIC TRANSMISSIONS. (4) The MIL illuminates only on the first detection of the malfunction.
(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 on first trip fault is detected.
(3)For diagnostic procedures, see appropriate DIAGNOSTICS article in AUTOMATIC TRANSMISSIONS.
(4)The MIL illuminates only on the first detection of the malfunction.

DIAGNOSTIC TROUBLE CODE INDEX

DIAGNOSTIC CIRCUIT CHECK

CAUTIONIf radio has anti-theft feature, obtain radio anti-theft code before disconnecting battery. If PCM is replaced, the immobilizer ECU should be replaced with it. PCM has specific individual information that must be registered in immobilizer ECU.

Note. For terminal identification, see appropriate illustration under TERMINAL IDENTIFICATION . For circuit and wire color identification, see ENGINE PERFORMANCE under MONTERO SYSTEM WIRING DIAGRAMS in ELECTRICAL.

DIAGNOSTIC TESTS

CAUTIONIf radio has anti-theft feature, obtain radio anti-theft code before disconnecting battery. If PCM is replaced, the immobilizer ECU should be replaced with it. PCM has specific individual information that must be registered in immobilizer ECU.

Note. For terminal identification, see appropriate illustration under TERMINAL IDENTIFICATION . For circuit and wire color identification, see ENGINE PERFORMANCE under MONTERO SYSTEM WIRING DIAGRAMS in ELECTRICAL.

DTC Set Criteria

  1. Throttle Position (TP) sensor voltage is 2 volts or less. Engine speed is less than 2000 RPM. Code will set when VAF sensor output frequency is 800 Hz or more for 2 seconds.
  2. TP sensor voltage is 1.5 volts or more. Engine speed is more than 2000 RPM. Code will set when VAF sensor output frequency if 60 Hz or less for 2 seconds.

Test Procedure

  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 12 (volume airflow sensor). Scan tool should read 10 Hz or more at idle. When engine is raced, frequency should increase in relation to increase in engine speed. If scan tool reads as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool does not read as specified, turn engine off and go to next step.
  2. Turn ignition on. Measure voltage between ground and VAF sensor connector terminal No. 7 (Green wire) by backprobing. see scheme 34 If 6.0 to 9.0 volts exists, go to next step. If 6.0 to 9.0 volts does not exist, go to step 5.
  3. Turn ignition off. Disconnect connectors at volume airflow (VAF) sensor and PCM D-107 harness connector for damage. see scheme 28 If connectors are in good condition, go to next step. If connectors are damaged, repair or replace as necessary. Go to step 9.
  4. Check continuity between VAF sensor connector terminal No. 7 and ground. If there is continuity, repair short to ground in Green wire between VAF sensor connector terminal No. 7 and PCM D-107 harness connector terminal No. 19. Go to step 9. If there is no continuity, replace VAF sensor. Go to step 9.
  5. Start engine and let idle. Backprobing, measure voltage between ground and terminal No. 7 (Green wire). With engine idling, voltage should be 1.0 volt or less. Rev engine to 3000 RPM and voltage should be 6.0 to 9.0 volts. If voltage is as specified, go to step 8. If voltage is not as specified, go to next step.
  6. Turn ignition off. Disconnect connectors at volume airflow (VAF) sensor and PCM D-107 harness connector for damage. If connectors are in good condition, go to next step. If connectors are damaged, repair or replace as necessary. Go to step 9.
  7. Check continuity between VAF sensor connector terminal No. 7 and PCM D-107 harness connector terminal No. 19. If there is continuity, replace PCM. Go to step 9. If there is no continuity, repair open in Green wire between VAF sensor connector terminal No. 7 and PCM D-107 harness connector terminal No. 19. Go to step 9.
  8. Replace VAF sensor. Test Drive vehicle following procedure in Other Monitor. See «OTHER MONITOR»(ref-135490-S39720580962002022200000). Return to shop and check for DTCs. If DTC P0101 is set, replace ECM/PCM. Then go to next step. If no DTC is set, inspection is complete.
  9. Test Drive vehicle following procedure in Other Monitor. See «OTHER MONITOR»(ref-135490-S39720580962002022200000). Return to shop and check for DTCs. If DTC P0101 is set, go to step 1 and recheck. If no DTC is set, inspection is complete.
  1. Engine speed is higher than 500 RPM.
  2. Volume airflow sensor output frequency has continued to be 3.3 Hz or lower for 2 seconds.
  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 12 (volume airflow sensor). Scan tool should read 10 Hz or more at idle. When engine is raced, frequency should increase in relation to increase in engine speed. If scan tool reads as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool does not read as specified, turn engine off and go to next step.
  2. Turn ignition on. Measure voltage between ground and VAF sensor connector terminal No. 4 (Red wire) by backprobing. see scheme 34 If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
  3. Turn ignition off. Disconnect VAF sensor connector. Turn ignition on. Measure voltage between ground and VAF sensor connector terminal No. 4 (Red wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair Red wire between VAF sensor and MFI relay. Go to step 13.
  4. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, repair Red wire between VAF sensor and MFI relay. Go to step 13.
  5. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  6. Disconnect VAF sensor harness connector. Measure voltage between ground and VAF sensor connector terminal No. 3 (White/Black wire). Voltage should be 4.8 and 5.2 volts. If voltage is as specified, go to step 9. If voltage is not as specified, go to next step.
  7. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair appropriate connector(s). Go to step 13. If problem does not exist, go to next step.
  8. Check for short to ground in White/Black wire between VAF sensor connector terminal No. 3 and PCM connector D-108 terminal No. 65. If problem exists, repair White/Black wire. Go to step 13. If problem does not exist, replace PCM. Go to step 13.
  9. Disconnect VAF sensor connector. Check continuity between ground and VAF sensor connector terminal No. 5 (Black wire). If continuity exists, go to next step. If continuity does not exist, repair or replace open circuit between ground and VAF sensor connector terminal No. 5 (Black wire). Then go to step 12.
  10. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace appropriate connector. Go to step 13. If problem does not exist, go to next step.
  11. Check for damage or open in Black wire between VAF sensor connector terminal No. 5 and PCM connector D-108 terminal No. 57. If problem exists, repair Black wire. Go to step 13. If problem does not exist, replace PCM. Go to step 13.
  12. Turn ignition off. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace appropriate connector. Go to next step. If problem does not exist, replace VAF sensor. Go to next step.
  13. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0102 is output, go to step 1 and retry diagnostic procedure. If DTC P0102 is not output, inspection is complete.
  1. Barometric pressure is lower than 11 psi (76 kPa).
  2. During 15 times of driving, the changes in sensor output voltage should be 0.015 volt (equivalent to 0.06 psi (0.4 kPa).

Note. BARO sensor is located in Volume Air Flow (VAF) sensor.

  1. Turn ignition on. Using scan tool, check if DTC P0107 is also set. If DTC P0107 is also set, troubleshoot «DTC P0107: BAROMETRIC PRESSURE SENSOR CIRCUIT LOW INPUT»(ref-135490-S26298383172003050100000) first, then recheck for DTC P0106. If DTC P0106 is the only code set, go to next step.
  2. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  3. Disconnect VAF sensor connector. see scheme 34 Check continuity between ground and VAF sensor connector terminal No. 5 (Black wire). If continuity exists, go to step 6. If continuity does not exist, go to next step.
  4. Check PCM connector D-108 connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  5. Check for continuity between PCM connector D-108 terminal No. 57 and VAF sensor connector terminal No. 5 (Black wire). If there is continuity, replace PCM and go to step 9. If there is no continuity, repair open circuit in Black wire between PCM connector D-108 terminal No. 57 and VAF sensor connector terminal No. 5. Then go to step 9.
  6. Turn ignition off. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  7. Check VAF sensor and PCM connector D-108 connectors for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 9. If problem does not exist, go to next step.
  8. Replace BARO sensor. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0106 is output, replace PCM. Go to next step. If DTC P0106 is not output, inspection is complete.
  9. Using scan tool, clear DTCs. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0106 is output, go to step 1 and retry diagnostic procedure. If DTC P0106 is not output, inspection is complete.
  1. At least 2 seconds have passed since engine started. Battery voltage is more than 8 volts. Code will set if BARO sensor output voltage is 4.5 volts or more, or 1.95 volts or less, for 10 seconds.
  2. BARO sensor output signal has continued to be approximately 7.2 psi (50 kPa) or lower (approximately 15,000 feet above sea level) for 10 seconds.
  1. Turn ignition on. Using scan tool, check data list item No. 25 (barometric pressure sensor). Compare reading against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool value is within specification, problem is intermittent. For troubleshooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value is not within specification, go to next step. BAROMETRIC PRESSURE SENSOR SPECIFICATIONS Altitude - Ft. (m) kPa 0 (0) 101 1969 (600) 95 3937 (1200) 88 5906 (1800) 81
  2. Measure voltage between ground and VAF sensor connector terminal No. 2 (Green/White wire) by backprobing. see scheme 34 Compare voltage against specification. See «BAROMETRIC PRESSURE SENSOR VOLTAGES»(ref-135490-S23382970252002022200000). If voltage is as specified, go to next step. If voltage is not as specified, go to step 7. BAROMETRIC PRESSURE SENSOR VOLTAGES 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 PCM 26-pin connector D-108 terminal No. 55 (Green/White wire) by backprobing. see scheme 28 Compare voltage against specification. See «BAROMETRIC PRESSURE SENSOR VOLTAGES»(ref-135490-S23382970252002022200000). If voltage is as specified, go to next step. If voltage is not as specified, go to step 6.
  4. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, go to next step.
  5. Using scan tool, check data list item No. 25 (barometric pressure sensor). Compare against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool value is within specification, problem is intermittent. For troubleshooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value is not within specification, replace PCM. Go to step 18.
  6. Turn ignition off. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, repair open in Green/White wire between VAF sensor connector terminal No. 2 and PCM connector D-108 terminal No. 55. Go to step 18.
  7. Backprobing wire, measure voltage between ground and VAF sensor connector terminal No. 1 (Green/Yellow wire). see scheme 34 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 12. If voltage is not as specified, go to next step.
  8. Measure voltage between ground and PCM connector D-108 terminal No. 46 (Green/Yellow wire) by backprobing. see scheme 28 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 10.
  9. Turn ignition off. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, repair open in Green/Yellow wire between VAF sensor connector terminal No. 1 and PCM connector D-108 terminal No. 46. Go to step 18.
  10. Turn ignition off. Disconnect VAF sensor connector and PCM connector D-108. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, go to next step.
  11. Check for continuity between ground and VAF sensor connector terminal No. 1 (Green/Yellow wire). If continuity exists, repair short to ground in Green/Yellow wire between VAF sensor and PCM. Go to step 18. If continuity does not exist, replace PCM. Go to step 18.
  12. Measure voltage between ground and VAF sensor connector terminal No. 5 (Black wire) by backprobing. Voltage should be 0.5 volt or less. If voltage is as specified, go to step 15. If voltage is not as specified, go to next step.
  13. Turn ignition off. Disconnect VAF sensor connector and PCM connector D-108. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, go to next step.
  14. Turn ignition off. Check VAF sensor connector terminal No. 5 (Black wire) and PCM connector D-108 terminal No. 57 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, replace PCM. Go to step 18.
  15. Turn ignition off. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, go to next step.
  16. Turn ignition off. Check PCM connector D-108 connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 18. If problem does not exist, go to next step.
  17. Check for damage or short to ground in Green/White wire between VAF sensor connector terminal No. 2 and PCM connector D-108 terminal No. 55. If problem exists, repair Green/White wire. Go to next step. If problem does not exist, replace VAF sensor. Go to next step.
  18. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0107 is output, go to step 1 and retry diagnostic procedure. If DTC P0107 is not output, inspection is complete.
  1. 2 seconds or more have passed since the starting sequence was completed.
  2. Battery positive voltage is higher than 8 volts.
  3. Barometric pressure sensor output signal has continued to be approximately 16 psi (113 kPa) or higher (approximately 4000 feet below sea level) for 10 seconds.
  1. Turn ignition on. Using scan tool, check data list item No. 25 (barometric pressure sensor). Compare reading against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool value is within specification, problem is intermittent. For troubleshooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value is not within specification, go to next step.
  2. Measure voltage between ground and VAF sensor connector terminal No. 2 (Green/White wire) by backprobing. see scheme 34 Compare voltage against specification. See «BAROMETRIC PRESSURE SENSOR VOLTAGES»(ref-135490-S23382970252002022200000). If voltage is as specified, go to next step. If voltage is not as specified, go to step 5.
  3. Turn ignition off. Disconnect VAF sensor connector and PCM connector D-108. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 12. If problem does not exist, go to next step.
  4. Turn ignition on. Using scan tool, check data list item No. 25 (barometric pressure sensor). Compare reading against specified value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool value is within specification, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value is not within specification, replace PCM. Go to step 12.
  5. Backprobing wire, measure voltage between ground and VAF sensor connector terminal No. 1 (Green/Yellow wire). see scheme 34 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 7. If voltage is not as specified, go to next step.
  6. Turn ignition off. Disconnect PCM connector D-108. Check PCM connector D-108 for loose, damaged, or corroded terminals. see scheme 28 If problem exists, repair or replace connector. Go to step 12. If problem does not exist, replace PCM. Go to step 12.
  7. Measure voltage between ground and VAF sensor connector terminal No. 5 (Black wire) by backprobing. Voltage should be 0.5 volt or less. If voltage is as specified, go to step 10. If voltage is not as specified, go to next step.
  8. Turn ignition off. Disconnect VAF sensor connector and PCM connector D-108. Check VAF sensor connector and PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 12. If problem does not exist, go to next step.
  9. Check for continuity between PCM connector D-108 terminal No. 57 and VAF sensor connector terminal No. 5 (Black wire). If there is continuity, replace PCM and go to step 12. If there is no continuity, repair open circuit in Black wire between PCM connector D-108 terminal No. 57 and VAF sensor connector terminal No. 5. Then go to step 12.
  10. Turn ignition off. Disconnect VAF sensor connector. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  11. Turn ignition off. Disconnect PCM connector D-108. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to next step. If problem does not exist, replace VAF sensor. Go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0108 is output, go to step 1 and retry diagnostic procedure. If DTC P0108 is not output, inspection is complete.
  1. Engine coolant temperature is higher than 169°F (76°C).
  2. Repeat steps 1 and 2, 5 or more times: Drive vehicle at speed higher than 31 MPH for longer than 60 seconds. Stop vehicle to a speed lower than 1 MPH for longer than 30 seconds.

Changes in IAT sensor output signal is lower than 1.8°F (1°C).

Note. IAT sensor is located in Volume Air Flow (VAF) sensor.

  1. Turn ignition on. Using scan tool, check data list item No. 13 (intake air temperature sensor). Remove the air intake hose from the VAF sensor. Turn ignition on. With a hot air gun heat the IAT sensor. See if the indicated temperature increases. NOTE: DO NOT allow temperature to increase over 176°F (80°C). Turn ignition off. Reattach air intake hose. If scan tool shows IAT sensor is working properly, problem is intermittent. For troubleshooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool shows IAT sensor is not working properly, go to next step.
  2. Measure resistance between VAF sensor connector terminals No. 5 and 6 (component side). see scheme 34 Compare resistance with expected value. See «INTAKE AIR TEMPERATURE SENSOR RESISTANCES»(ref-135490-S27518660602002022200000). Heat IAT sensor (in VAF sensor) with hot air gun. Resistance should decrease as IAT sensor temperature increases. If resistance values are as specified, go to next step. If resistance values are not as specified, replace VAF sensor. Go to step 9. INTAKE AIR TEMPERATURE SENSOR RESISTANCES Temperature - °F (°C) k/ohms 32 (0) 5.3-6.7 68 (20) 2.3-3.0 104 (40) 1.0-1.5 176 (80).30-.42
  3. Turn ignition off. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  4. Turn ignition off. Check for continuity between ground and VAF sensor connector terminal No. 5 (Black wire). If continuity exists, go to step 2. If continuity does not exist, go to next step.
  5. Turn ignition off. Check PCM D-108 connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  6. Disconnect VAF sensor connector and PCM D-108 connector. Measure continuity between VAF sensor connector terminal No. 6 (Red/Blue wire) and PCM D-108 connector terminal No. 64. If there is continuity, replace PCM and go to step 9. If there is no continuity, repair open Red/Blue wire between VAF sensor connector terminal No. 6 and PCM D-108 connector terminal No. 64. Then go to step 9.
  7. Turn ignition off. Check PCM D-108 connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  8. Disconnect VAF sensor connector and PCM D-108 connector. Measure continuity between VAF sensor connector terminal No. 6 (Red/Blue wire) and PCM D-108 connector terminal No. 64. If there is continuity, replace PCM and go to step 9. If there is no continuity, Repair open Red/Blue wire between VAF sensor connector terminal No. 6 and PCM D-108 connector terminal No. 64. Then go to step 9.
  9. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0111 is output, 1 and retry diagnostic procedure. If DTC P0111 is not output, inspection is complete.

At least 2 seconds have passed since starting sequence was completed. Intake air temperature sensor output voltage has continued to be 0.2 volt or lower (corresponding to an intake air temperature of 239°F (115°C) or higher) for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 13 (intake air temperature sensor). If scan tool value approximately matches air temperature, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value does not match air temperature, go to next step.
  2. Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 6. If problem does not exist, go to next step.
  3. Disconnect VAF sensor connector. see scheme 34 Measure resistance between IAT sensor terminals No. 5 and 6 (component side). Resistance should be 0.30-1.0 K 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 PCM connector D-108. Check continuity between ground and VAF sensor connector terminal No. 6 (Red/Blue wire). If there is no continuity, go to next step. If continuity exists, repair short to ground in Red/Blue wire between VAF sensor connector terminal No. 6 and PCM connector D-108 terminal No. 64. see scheme 28 Then go to step 6.
  5. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to next step. If problem does not exist, replace PCM. Go to next step.
  6. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0112 is output, go to step 1 and retry diagnostic procedure. If DTC P0112 is not output, inspection is complete.

At least 2 seconds have passed since starting sequence was completed. Intake air temperature sensor output voltage has continued to be 4.5 volts or higher (corresponding to an intake air temperature of -40°F (-40°C) or lower) for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 13 (intake air temperature sensor). If scan tool value approximately matches air temperature, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value does not match air temperature, go to next step.
  2. Disconnect VAF sensor connector. see scheme 34 Check VAF sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  3. Measure resistance between IAT sensor terminals No. 5 and 6 (component side). Resistance should be 0.30-1.0 K 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 on. Measure voltage between connector terminal No. 6 (Red/Blue wire) and ground. Voltage should be between 4.5-4.9 volts. If voltage is as specified, go to step 8. If voltage is not as specified, go to next step.
  5. Backprobing wire, measure voltage at PCM connector D-108 terminal No. 64 (Red/Blue wire). see scheme 28 Voltage should be between 4.5-4.9 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  6. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, repair Red/Blue wire between PCM connector D-108 terminal No. 64 and VAF sensor connector terminal No. 6. Then go to step 11.
  7. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, replace PCM. Then go to step 11.
  8. Disconnect VAF sensor connector. Check continuity between ground and VAF sensor connector terminal No. 5 (Black wire). If continuity exists, replace PCM. Then go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  10. Check continuity between VAF sensor connector terminal No. 6 (Red/Blue wire) and PCM connector D-108 terminal No. 64. If there is continuity, replace PCM and go to next step. If there is no continuity, repair Red/Blue wire between VAF sensor connector terminal No. 6 (Red/Blue wire) and PCM connector D-108 terminal No. 64. Then go to next step.
  11. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0113 is output, go to step 1 and retry diagnostic procedure. If DTC P0113 is not output, inspection is complete.
  1. Engine coolant temperature was 44.6°F (7°C) or more immediately before engine was stopped at last drive.
  2. Engine coolant temperature was 44.6°F (7°C) or more when engine started.
  3. Engine coolant temperature fluctuates 1.8°F (1°C) after 5 minutes have passed since engine started. PCM will not count time when Volume Air Flow (VAF) sensor average output frequency is 70 Hz or less, or fuel is shut off.
  4. Engine coolant temperature fluctuates 1.8°F (1°C) after 5 minutes have passed since engine started. Time is not counted if intake air temperature is 140°F (60°C) or more, engine speed is less than 1500 RPM, volumetric efficiency is less than 25 percent, or fuel is being shut off. PCM runs monitor only once during drive cycle.
  5. Engine coolant temperature fluctuates 1.8°F (1°C) after 5 minutes have passed since engine started. Time is not counted during fuel shut-off operation.
  6. There is only 1 monitor during 1 drive cycle.
  1. Turn ignition on. Using scan tool, check data list item No. 21 (engine coolant temperature sensor). If scan tool value approximately matches engine coolant temperature, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value does not match engine coolant temperature, go to next step.
  2. Measure voltage between ground and ECT sensor connector terminal No. 1 (Yellow/Green wire) by backprobing. see scheme 17 Compare voltage to expected value. See «ECT SENSOR VOLTAGES»(ref-135490-S25241441492002022200000). If voltage is as specified, go to next step. If voltage is not as specified, go to step 5. ECT SENSOR VOLTAGES 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 (60) 0.7-0.9 176 (80) 0.3-0.9
  3. Turn ignition off. Disconnect ECT sensor connector. Check ECT sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  4. Reconnect ECT sensor connector. Turn ignition on. Using scan tool, check data list item No. 21 (engine coolant temperature sensor). If scan tool value approximately matches engine coolant temperature, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value does not match engine coolant temperature, replace PCM. Go to step 14.
  5. Turn ignition off. Disconnect ECT sensor connector. Check ECT sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  6. Turn ignition on. Measure voltage between ground and ECT sensor connector terminal No. 1 (Yellow/Green wire). Voltage should be 4.8-4.9 volts. If voltage is as specified, go to step 8. If voltage is not as specified, go to next step.
  7. Turn ignition off. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, replace PCM. Go to step 14.
  8. Turn ignition off. Check for continuity between ground and ECT sensor connector terminal No. 2 (Black wire). If continuity exists, go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  10. Check for damage or open in Black wire between ECT sensor connector terminal No. 2 and PCM connector D-108 terminal No. 57. If problem exists, repair Black wire. Go to step 14. If problem does not exist, replace PCM. Go to step 14.
  11. Remove ECT sensor. Immerse sensor portion of ECT sensor in hot water and check resistance between ECT sensor connector terminals. Compare resistance with expected value. See «ECT SENSOR RESISTANCES»(ref-135490-S01960450622002022200000). If resistance is as specified, go to next step. If resistance is not as specified, replace ECT sensor. Go to step 14. ECT SENSOR RESISTANCES 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 NOTE: To install ECT sensor, apply thread sealer to ECT sensor threads and tighten ECT sensor to 15-29 ft. lbs. (19-39 N.m).
  12. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  13. With PCM D-108 connector and ECT connector disconnected, check Yellow/Green wire for continuity between ECT sensor connector terminal No. 1 and PCM connector D-108 terminal No. 44. If there is no continuity, repair open in Yellow/Green wire. Go to next step. If problem does not exist, replace PCM. Go to next step.
  14. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0116 is output, go to 1 and retry diagnostic procedure. If DTC P0116 is not output, inspection is complete.

At least 2 seconds have passed since starting sequence was completed. Engine coolant temperature sensor output voltage has continued to be 0.1 volt or lower (corresponding to an coolant temperature of 284°F (140°C) or higher) for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 21 (engine coolant temperature sensor). If scan tool value approximately matches engine coolant temperature, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value does not match engine coolant temperature, go to next step.
  2. Turn ignition off. Disconnect ECT sensor connector. see scheme 17 Check ECT sensor connector for loose, damaged or corroded terminals. If problem exists, repair or replace connector. Go to step 6. If problem does not exist, go to next step.
  3. Disconnect PCM D-108 connector. see scheme 28 Check continuity between ground and PCM D-108 connector terminal No. 44 (Yellow/Green wire). If continuity exists, go to next step. If continuity does not exist, repair wire between PCM D-108 connector terminal No. 44 (Yellow/Green wire) and ECT sensor connector terminal No. 1.
  4. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 6. If problem does not exist, go to next step.
  5. Remove ECT sensor. Immerse sensor portion of ECT sensor in hot water and check resistance between ECT sensor connector terminals. Compare resistance with expected value. See «ECT SENSOR RESISTANCES»(ref-135490-S01960450622002022200000). If resistance is as specified, replace PCM. Go to next step. If resistance is not as specified, replace ECT sensor. Go to next step. NOTE: To install ECT sensor, apply thread sealer to ECT sensor threads and tighten ECT sensor to 15-29 ft. lbs. (19-39 N.m).
  6. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0117 is output, go to 1 and retry diagnostic procedure. If DTC P0117 is not output, inspection is complete.

At least 2 seconds have passed since starting sequence was completed. Engine coolant temperature sensor output voltage has continued to be 4.5 volts or higher (corresponding to an coolant temperature of -49°F (-45°C) or lower) for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 21 (engine coolant temperature sensor). If scan tool value approximately matches engine coolant temperature, problem is intermittent. For trouble shooting, see «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool value does not match engine coolant temperature, go to next step.
  2. Turn ignition off. Disconnect ECT sensor connector. see scheme 17 Check ECT sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  3. Turn ignition on. Measure voltage between ground and ECT sensor connector terminal No. 1 (Yellow/Green wire). Voltage should be 4.8-4.9 volts. If voltage is as specified, go to step 7. If voltage is not as specified, go to next step.
  4. Measure voltage between ground and PCM connector D-108 terminal No. 44 (Yellow/Green wire) by backprobing. Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6.
  5. Turn ignition off. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, repair Yellow/Green wire between PCM connector D-108 terminal No. 44 and ECT sensor connector terminal No. 1. Go to step 11.
  6. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, replace PCM. Go to step 11.
  7. Check for continuity between ground and ECT sensor connector terminal No. 2 (Black wire). If continuity exists, go to step 10. If continuity does not exist, go to next step.
  8. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  9. Check continuity between ECT sensor connector terminal No. 2 (Black wire) and PCM connector D-108 terminal No. 57. If continuity exists, replace PCM. Go to step 11. If continuity does not exist, repair Black wire between ECT sensor connector terminal No. 2 and PCM connector D-108 terminal No. 57. Then go to step 11.
  10. Remove ECT sensor. Immerse sensor portion of ECT sensor in hot water and check resistance between ECT sensor connector terminals. Compare resistance with expected value. See «ECT SENSOR RESISTANCES»(ref-135490-S01960450622002022200000). If resistance is as specified, replace PCM. Go to next step. If resistance is not as specified, replace ECT sensor. Go to next step. NOTE: To install ECT sensor, apply thread sealer to ECT sensor threads and tighten ECT sensor to 15-29 ft. lbs. (19-39 N.m).
  11. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0118 is output, go to 1 and retry diagnostic procedure. If DTC P0118 is not output, inspection is complete.
  1. At least 2 seconds have passed since engine started. Engine speed is higher than 2000 RPM. Volumetric efficiency is higher than 60 percent. Code will set if TP sensor output voltage has continued to be 0.8 volt or lower for 2 seconds.
  2. At least 2 seconds have passed since engine started. Engine speed is lower than 3000 RPM. Volumetric efficiency is lower than 30 percent. Code will set if TP sensor output voltage has continued to be 4.6 volts or higher for 2 seconmds.
  1. Turn ignition on. Using scan tool, check data list item No. 14 (throttle position sensor). Turn ignition on. 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 voltages are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If voltages are not as specified, go to next step.
  2. Turn ignition off. Disconnect TP sensor 4-pin connector. see scheme 30 Check TP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  3. Measure resistance between TP sensor terminals No. 1 and 4 (component side). Resistance should be 3.5-6.5 K ohms. Also, measure resistance between TP sensor terminals No. 1 and 3 (component side) while moving throttle valve from idle position to full throttle position. Resistance should change smoothly in proportion to the opening angle of throttle valve. If both resistance checks are as specified, go to next step. If either resistance checks are not as specified, replace TP sensor. Go to step 14.
  4. Turn ignition on. Measure voltage between ground and TP sensor connector terminal No. 4 (Green/Yellow wire). Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 7. If voltage is not as specified, go to next step.
  5. Turn ignition off. Disconnect PCM connector D-108. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  6. Check for open or short to ground in Green/Yellow wire between TP sensor connector terminal No. 4 and PCM connector D-108 terminal No. 46. see scheme 28 If problem exists, repair Green/Yellow wire between TP sensor and PCM. Go to step 14. If problem does not exist, replace PCM. Go to step 14.
  7. Turn ignition off. Check for continuity between ground and TP sensor connector terminal No. 1 (Black wire). If continuity exists, go to step 10. If continuity does not exist, go to next step.
  8. Disconnect PCM connector D-108. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  9. Check for open or damage in Black wire between TP sensor connector terminal No. 1 and PCM connector D-108 terminal No. 57. If problem exists, repair Black wire. Go to step 14. If problem does not exist, replace PCM. Go to step 14.
  10. Check PCM connectors D-108 and D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 14. If problem does not exist, go to next step.
  11. Check for open or short to ground in Yellow/Red wire between TP sensor connector terminal No. 3 and PCM connector D-109 terminal No. 78. If problem exists, repair Yellow/Red wire. Go to step 14. If problem does not exist, go to next step.
  12. Check TP sensor adjustment. See TP SENSOR ADJUSTMENT for «ECLIPSE, ECLIPSE SPYDER, GALANT, MONTERO & MONTERO SPORT»(ref-135481-S14399802092002022200000) under THROTTLE POSITION (TP) SENSOR & ACCELERATOR PEDAL POSITION SENSOR in ON-VEHICLE ADJUSTMENTS article. If TP sensor is out of adjustment, adjust TP sensor. Go to step 14. If TP sensor is not out of adjustment, go to next step.
  13. Turn ignition on. Using scan tool, check data list item No. 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 voltages are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If voltages are not as specified, replace PCM. Go to next step.
  14. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0121 is output, go to step 1 and retry diagnostic procedure. If DTC P0121 is not output, inspection is complete.

At least 2 seconds have passed since starting sequence was completed. TPS output voltage has continued to be 0.2 volt or lower for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 14 (throttle position sensor). Turn ignition on. 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 voltages are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If voltages are not as specified, go to next step.
  2. Turn ignition off. Disconnect TP sensor 4-pin connector. see scheme 30 Check TP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 10. If problem does not exist, go to next step.
  3. Turn ignition on. Measure voltage between ground and TP sensor connector terminal No. 4 (Green/Yellow wire). Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 6. If voltage is not as specified, go to next step.
  4. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 10. If problem does not exist, go to next step.
  5. Check for open or short to ground in Green/Yellow wire between TP sensor connector terminal No. 4 and PCM connector D-108 terminal No. 46. If problem exists, repair Green/Yellow wire. Go to step 10. If problem does not exist, replace PCM. Go to step 10.
  6. Measure resistance between TP sensor terminals No. 1 and 4 (component side). Resistance should be 3.5-6.5 K ohms. Also, measure resistance between TP sensor terminals No. 1 and 3 (component side) while moving throttle valve from idle position to full throttle position. Resistance should change smoothly in proportion to the opening angle of throttle valve. If both resistance checks are as specified, go to next step. If either resistance checks are not as specified, replace TP sensor. Go to step 10.
  7. Check PCM connectors D-108 and D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 10. If problem does not exist, go to next step.
  8. Check for open or short to ground in Yellow/Red wire between TP sensor connector terminal No. 3 and PCM connector D-109 terminal No. 78. If problem exists, repair Yellow/Red wire. Go to step 10. If problem does not exist, go to next step.
  9. Turn ignition on. Using scan tool, check data list item No. 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 voltages are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If voltages are not as specified, replace PCM. Go to next step.
  10. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0122 is output, go to step 1 and retry diagnostic procedure. If DTC P0122 is not output, inspection is complete.

At least 2 seconds have passed since starting sequence was completed. Engine speed is lower than 1000 RPM. Volumetric efficiency is lower than 60 percent. TPS output voltage has continued to be 2 volts or higher for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 14 (throttle position sensor). Turn ignition on. 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 voltages are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If voltages are not as specified, go to next step.
  2. Turn ignition off. Disconnect TP sensor 4-pin connector. see scheme 30 Check TP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 8. If problem does not exist, go to next step.
  3. Check for continuity between ground and TP sensor connector terminal No. 1 (Black wire). If continuity exists, go to step 6. If continuity does not exist, go to next step.
  4. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 8. If problem does not exist, go to next step.
  5. Check for open or damage in Black wire between TP sensor connector terminal No. 1 and PCM connector D-108 terminal No. 57. If problem exists, repair Black wire. Go to step 8. If problem does not exist, replace PCM. Go to step 8.
  6. Measure resistance between TP sensor terminals No. 1 and 4 (component side). Resistance should be 3.5-6.5 K ohms. Also, measure resistance between TP sensor terminals No. 1 and 3 (component side) while moving throttle valve from idle position to full throttle position. Resistance should change smoothly in proportion to the opening angle of throttle valve. If both resistance checks are as specified, go to next step. If either resistance checks are not as specified, replace TP sensor. Go to step 8.
  7. Turn ignition on. Using scan tool, check data list item No. 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 voltages are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If voltages are not as specified, replace PCM. Go to next step.
  8. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0123 is output, go to step 1 and retry diagnostic procedure. If DTC P0123 is not output, inspection is complete.

Engine coolant temperature decreases from higher than 104°F (40°C) to lower than 104°F (40°C). Then the engine coolant temperature has continued to be 104°F (40°C) or lower for 5 seconds. At least 60-300 seconds have passed for engine coolant temperature to rise to about 44.6°F (7°C) after starting sequence was completed.

Note. Time is not counted when fuel is shut off.

  1. Turn ignition on. Using scan tool, check data list item No. 21 (engine coolant temperature sensor). Turn ignition on. The engine coolant temperature and temperature indicated on the scan tool should approximately match. If the engine coolant temperature sensor is operating properly, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If readings do not match, go to next step.
  2. Turn ignition on. While backprobing Yellow/Green wire at ECT sensor, measure voltage between ground ECT sensor terminal No. 1. see scheme 17 Refer to «ECT SENSOR VOLTAGES»(ref-135490-S25241441492002022200000). If voltage is as specified, go to next step. If voltage is not as specified, go to step 5.
  3. Turn ignition off. Disconnect ECT sensor connector. see scheme 17 Check ECT sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  4. Turn ignition on. Using scan tool, check data list item No. 21 (engine coolant temperature sensor). Turn ignition on. The engine coolant temperature and temperature indicated on the scan tool should approximately match. If the engine coolant temperature sensor is operating properly, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If readings do not match, replace PCM. Go to step 14.
  5. Turn ignition off. Disconnect ECT sensor connector. Check ECT sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  6. Turn ignition on. Measure voltage between ground and ECT sensor connector terminal No. 1 (Yellow/Green wire). Voltage should be 4.8-4.9 volts. If voltage is as specified, go to step 8. If voltage is not as specified, go to next step.
  7. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, replace PCM. Go to step 14.
  8. Check for continuity between ground and ECT sensor connector terminal No. 2 (Black wire). If continuity exists, go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  10. Check continuity between ECT sensor connector terminal No. 2 (Black wire) and PCM connector D-108 terminal No. 57. If continuity exists, replace PCM. Go to step 14. If continuity does not exist, repair Black wire between ECT sensor connector terminal No. 2 and PCM connector D-108 terminal No. 57. Then go to step 14.
  11. Remove ECT sensor. Immerse sensor portion of ECT sensor in hot water and check resistance between ECT sensor connector terminals. Compare resistance with expected value. See «ECT SENSOR RESISTANCES»(ref-135490-S01960450622002022200000). If resistance is as specified, go to next step. If resistance is not as specified, replace ECT sensor. Go to step 14. NOTE: To install ECT sensor, apply thread sealer to ECT sensor threads and tighten ECT sensor to 15-29 ft. lbs. (19-39 N.m).
  12. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  13. With PCM D-108 connector and ECT connector disconnected, check Yellow/Green wire for continuity between ECT sensor connector terminal No. 1 and PCM connector D-108 terminal No. 44. If there is no continuity, repair open in Yellow/Green wire. Go to next step. If problem does not exist, replace PCM. Go to next step.
  14. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0125 is output, go to step 1 and retry diagnostic procedure. If DTC P0125 is not output, inspection is complete.

Engine coolant temperature is 14-171°F (-10-77°C) when engine is started. Engine coolant temperature minus intake air temperature is 9°F (5°C) or less when engine is started. Intake air temperature is 9°F (5°C) or less when engine is started. Volume airflow sensor output is 100 Hz or less for 300 seconds or less. Code will set when engine coolant temperature at engine start is 68°F (20°C) or more and it takes longer than 13 to 20 minutes for engine coolant temperature to increase to 171°F (77°C) or more.

Check cooling system. If problem exists, repair or replace cooling system. If problem does not exist, replace PCM. Check that DTC P0128 does not reset.

After engine starts, right front HO2S signal is 0.2 volt or less for 3 minutes or more. Engine coolant temperature is more than 169°F (76°C). Engine speed is more than 1200 RPM. Volumetric efficiency is more than 25 percent. Code will set when input voltage supplied to Powertrain Control Module (PCM) interface circuit is more than 4.5 volts when 5 volts are applied to right front HO2S output line through a resistor. Monitor runs only once during drive cycle for 7 seconds.

  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 39 (right front heated oxygen sensor). When engine is revved, right front HO2S output voltage should read 0.6-1.0 volt. When engine is idling, right front HO2S output voltage should alternate between less than 0.4 volt and more than 0.6 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. With engine running, measure voltage between ground and right front HO2S connector terminal No. 4 (White wire) by backprobing. see scheme 22 With engine speed at 2500 RPM, right front HO2S voltage should alternate between about zero volts and 0.8 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  3. With engine running, measure voltage between ground and PCM connector D-109 terminal No. 72 (White wire) by backprobing. see scheme 28 With engine speed at 2500 RPM, right front HO2S voltage should alternate between about zero volts and 0.8 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6.
  4. Turn ignition off. Check right front HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, go to next step.
  5. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 39 (right front heated oxygen sensor). When engine is repeatedly revved, right front HO2S output voltage should read 0.6-1.0 volt. When engine is idling, right front HO2S output voltage should alternate between less than 0.4 volt and more than 0.6 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, replace PCM. Go to step 15.
  6. Turn ignition off. Check right front HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, repair White wire between right front HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 72. Go to step 15.
  7. Turn ignition off. Disconnect right front HO2S connector. Check right front HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  8. Check for continuity between ground and right front HO2S connector terminal No. 2 (Black wire). see scheme 22 If continuity exists, go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  10. Disconnect PCM connector D-108 and right front HO2S connector(s). Check continuity in Black wire between right front HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair Black wire. Go to step 15. If continuity exists, replace PCM. Go to step 15.
  11. Check PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  12. Disconnect PCM connector D-108 and right front HO2S connector(s). Check continuity in Black wire between right front HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair Black wire. Go to step 15. If continuity exists, go to next step.
  13. Disconnect right front HO2S connector. see scheme 22 Check continuity between right front HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 72 (White wire). There should be continuity. Check continuity between ground and right front HO2S connector terminal No. 4 (White wire). There should be no continuity. Reconnect PCM connectors. Turn ignition on. Measure voltage at right front HO2S connector terminal 4 (White wire). There should be less than 0.8 volt. If problem exists, repair open, short to ground or short to battery voltage in White wire. Go to step 15. If problem does not exist, go to next step.
  14. Ensure engine is warmed up. Connect jumper wire between battery positive terminal and right front HO2S connector terminal No. 1 (component side). Connect jumper wire between battery negative terminal and right front HO2S connector terminal No. 3 (component side). Connect digital voltmeter between right front HO2S connector terminals No. 2 and 4 (component side). Start engine. While repeatedly revving engine, measure right front HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, replace PCM. Go to next step. If voltage is not as specified, replace right front HO2S. Go to next step.
  15. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0132 is output, go to step 1 and retry diagnostic procedure. If DTC P0132 is not output, inspection is complete.

Engine coolant temperature is more than 122°F (50°C). Engine speed is 1250-3000 RPM. Volumetric efficiency is 20-60 percent. Intake air 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). Engine is under closed loop air/fuel control and not in idle state. Short term fuel trim is between -30 and 25 percent. More than 3 seconds have elapsed after the above mentioned conditions have been met. Monitor runs 3 times for 12 seconds per drive cycle. Code will set when front HO2S sends alternating lean and rich signals 8 times or less in 12 seconds.

  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 39 (right front heated oxygen sensor). When engine is revved, right front HO2S output voltage should read 0.6-1.0 volt. When engine is idling, right front HO2S output voltage should alternate between less than 0.4 volt and more than 0.6 volt 10 times or more within 10 seconds. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000) . If scan tool readings are not as specified, replace HO2S. Go to next step.
  2. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor pattern. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) under OBD-II DRIVE CYCLES in VERIFYING REPAIRS. Check for DTCs. If DTC P0133 is output, retry diagnostic procedure. If DTC P0133 is not output, inspection is complete.

Thirty seconds or more have passed since the starting sequence was completed. Engine coolant temperature is higher than 169°F (76°C). Engine speed is higher than 1200 RPM. Volumetric efficiency is higher than 30 percent. Throttle position sensor output voltage is lower than 4 volts. Except while fuel is being shut off. Monitoring time is 30 seconds. Code will set when right front HO2S output voltage does not get across 0.5 volt within about 30 seconds.

  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 69 (right rear heated oxygen sensor). When engine is revved, right rear HO2S output voltage should read 0.6-1.0 volt. If scan tool readings are as specified, go to next step. If scan tool readings are not as specified, refer to DTCs P0137, P0138 or P0139 diagnostic procedures.
  2. Check for exhaust leaks. If any exhaust leaks are found, repair as necessary. Go to step 13. If no exhaust leaks are found, go to next step.
  3. Check the intake system for vacuum leaks. If any vacuum leaks are found, repair as necessary. Go to step 13. If no vacuum leaks are found, go to next step.
  4. Turn ignition off. Disconnect right front HO2S connector. see scheme 22 Check right front HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  5. Ensure engine is warmed up. Connect jumper wire between battery positive terminal and right front HO2S connector terminal No. 1 (component side). Connect jumper wire between battery negative terminal and right front HO2S connector terminal No. 3 (component side). Connect digital voltmeter between right front HO2S connector terminals No. 2 and 4 (component side). Start engine. While repeatedly revving engine, measure right front HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, replace right front HO2S. Go to step 13.
  6. Turn ignition off. Disconnect fuel injector intermediate connector. see scheme 20 Check fuel injector intermediate connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  7. Measure resistance of right bank injectors at the fuel injector intermediate connector. Measure between fuel injector intermediate connector terminals No. 8 and 3 (cylinder No. 1), terminals No. 8 and 1 (cylinder No. 3) and terminals No. 8 and 6 (cylinder No. 5). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, go to step 10. If resistance is not as specified, go to next step.
  8. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check the right bank injector connector that deviates from the specified value of resistance at step 7). see scheme 19 If connectors are OK, go to next step. If connectors are not OK, repair or replace as necessary. Then go to step 13.
  9. Check the right bank injector terminals (component side) that deviates from the specified value of resistance at step 7. Measure resistance of right bank injectors (component side). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, repair damaged wire between fuel injector intermediate connector and right bank injector connector. Then go to step 13. If resistance is not as specified, replace the injector. Then go to step 13. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES.
  10. Disconnect and check PCM connectors D-108 and D-109 for loose, damaged, or corroded terminals. see scheme 28 If problem exists, repair or replace connector(s). Go to step 13. If problem does not exist, go to next step.
  11. Disconnect right front HO2S connector. see scheme 22 Check continuity between right front HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 72 (White wire). Check continuity between ground and right front HO2S connector terminal No. 4 (White wire). Reconnect PCM connectors. Turn ignition on. Measure voltage at right front HO2S connector terminal 4 (White wire). There should be less than 0.8 volt. If problem exists, repair open, short to ground or short to battery voltage in White wire. Go to step 13. If problem does not exist, go to next step.
  12. Disconnect PCM connector D-107 and right bank fuel injector connectors. Check continuity between right bank injectors connectors terminals No. 2 and PCM connector D-107. See «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (RIGHT BANK)»(ref-135490-S26709373942003050200000). Check continuity between ground and right bank injectors wires. See «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (RIGHT BANK)»(ref-135490-S26709373942003050200000). Reconnect PCM connectors. Turn ignition on. Measure voltage at fuel injector intermediate connector. See «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (RIGHT BANK)»(ref-135490-S26709373942003050200000). There should be battery voltage. If problem exists, repair open or short to ground suspect wire. Go to step 14. If problem does not exist, go to next step. INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (RIGHT BANK) Injector No. & Wire Color Injector Intermediate Connector Terminal No. PCM Connector D-107 Terminal No. Inj. No. 1 (Yellow/Blue) (1) No. 3 No. 1 Inj. No. 3 (Light Green) (1) No. 1 No. 24 Inj. No. 5 (Blue) (1) No. 6 No. 10 (1) The terminal referenced to is F.I. connector terminal No. 2.
  13. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES. If fuel pressure is OK, replace PCM. Then go to next step. If fuel pressure is not as specified, repair as necessary. Go to next step.
  14. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0134 is output, go to step 1 and retry diagnostic procedure. If DTC P0134 is not output, inspection is complete.

60 seconds have elapsed from the start of previous monitoring. Engine coolant temperature is more than 68°F (20°C). Right front HO2S heater is on. Battery voltage is 11-16 volts. Code will set if right front HO2S heater current is less than 0.6 amp, or more than 7.5 amps, for 4 seconds. One monitor runs each drive cycle.

  1. Turn ignition off. Disconnect right front HO2S 4-pin connector. Check right front HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  2. Measure resistance between right front HO2S connector terminals No. 1 and 3 (component side). see scheme 22 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 right front HO2S. Go to step 12.
  3. Turn ignition on. Measure voltage between ground and right front HO2S connector terminal No. 1 (Red wire). If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
  4. Turn ignition off. Remove MFI relay. see scheme 4 Check MFI relay connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, repair Red wire between right front HO2S and MFI relay. Go to step 12.
  5. Turn ignition off. Reconnect right front HO2S connector. Turn ignition on. Measure voltage between ground and PCM connector D-107 terminal No. 4 (Blue/Red wire) by backprobing. see scheme 28 If battery voltage exists, go to step 8. If battery voltage does not exist, go to next step.
  6. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  7. With PCM connector D-107 and right front HO2S connector disconnected, check continuity between right front HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 4 (Blue/Red wire). Continuity should exist. see scheme 28 Then check continuity between ground and right front HO2S connector terminal No. 3 (Blue/Red wire). Continuity should not exist. If problem exists, repair open or short in Blue/Red wire. Go to step 12. If problem does not exist, replace PCM. Go to step 12.
  8. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  9. Disconnect right front HO2S connector and remove MFI relay. Check continuity between ground and front HO2S connector terminal No. 1 (Red wire). see scheme 22 Continuity should not exist.. If continuity exists, repair short to ground in Red wire. Go to step 12. If continuity does not exist, go to next step.
  10. With PCM connector D-107 and right front HO2S connector disconnected, check continuity between right front HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 4 (Blue/Red wire). Continuity should exist. see scheme 28 Then check continuity between ground and right front HO2S connector terminal No. 3 (Blue/Red wire). Continuity should not exist. If problem exists, repair open or short in Blue/Red wire. Go to step 12. If problem does not exist, go to next step.
  11. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0135 is output, replace PCM. Go to next step. If DTC P0135 is not output, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0135 is output, retry diagnostic procedure. If DTC P0135 is not output, inspection is complete.

Right rear HO2S signal voltage is 0.15 volt or less for 3 minutes or more after 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 25 percent. At least 20 seconds have passed since fuel shut off control was cancelled. Volume Air Flow (VAF) sensor output frequency is 100 Hz or more. Right front HO2S outputs 0.5 volt or more. Right rear HO2S signal voltage is 0.078 volt or less for 3 minutes or more after engine starts. Code will set when making air/fuel ratio 15 percent richer for 10 seconds does not increase rear HO2S output voltage beyond 0.15 volt. Monitor is run once per drive cycle for 10 seconds.

  1. Start engine. Using scan tool, check data list item No. 69 (right rear heated oxygen sensor). When engine is revved, right rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Disconnect right rear HO2S sensor connector. Connect jumper wire between right rear HO2S connector terminal No. 1 (component side) and battery positive terminal. Connect second jumper wire between right rear HO2S connector terminal No. 3 (component side) and battery negative terminal. Connect digital voltmeter between right rear HO2S connector terminals No. 2 and 4 (component side). Start engine. When engine is at normal operating temperature, repeatedly rev engine and check right rear HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, replace right rear HO2S. Go to step 5.
  3. Turn ignition off. Check right rear HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 5. If problem does not exist, go to next step.
  4. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Disconnect right rear HO2S connector and PCM connector D-109. Check for continuity between ground and right rear HO2S connector terminal No. 4 (White wire). see scheme 22 If continuity exists, repair short circuit in White wire between right rear HO2S connector and PCM connector D-109. Then go to next step. If continuity does not exist, replace PCM. Then go to next step.
  5. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0137 is output, go to step 1 and retry diagnostic procedure. If DTC P0137 is not output, inspection is complete.

Right rear HO2S signal voltage is 0.15 volt or less for 3 minutes or more after 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 25 percent. Code will set when input voltage supplied to Powertrain Control Module (PCM) interface circuit is more than 4.5 volts when 5 volts is applied to rear HO2S output line through a resistor. Monitor is run once per drive cycle for 7 seconds.

  1. Start engine. Using scan tool, check data list item No. 69 (right rear heated oxygen sensor). When engine is revved, right rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Measure voltage between ground and right rear HO2S connector terminal No. 4 (White wire) by backprobing. see scheme 22 When engine is revved, right rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  3. Measure voltage between ground and PCM connector D-109 terminal No. 74 (White wire) by backprobing. see scheme 28 When engine RPM is held at 2500 RPM while engine is warming up, right rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6.
  4. Turn ignition off. Check right rear HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, go to next step.
  5. Start engine. Using scan tool, check data list item No. 69 (right rear heated oxygen sensor). When engine is revved, right rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, replace PCM. Go to step 15.
  6. Turn ignition off. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Check right rear HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, repair White wire between right rear HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 74. Go to step 15. see scheme 22and see scheme 28.
  7. Turn ignition off. Disconnect right rear HO2S. Check right rear HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  8. Check for continuity between ground and right rear HO2S connector terminal No. 2 (Black wire). see scheme 22 If continuity exists, go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. see scheme 28 If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  10. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Check continuity between ground and Black wire between right rear HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair open in Black wire. Go to step 15. If continuity exists, replace PCM. Go to step 15.
  11. Check PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  12. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Check continuity between ground and Black wire between right rear HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair open in Black wire. Go to step 15. If continuity exists, go to next step.
  13. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Disconnect right rear HO2S connector and PCM connector D-109. Check for continuity between ground and right rear HO2S connector terminal No. 4 (White wire). see scheme 22and see scheme 28. If continuity exists, repair short circuit in White wire between right rear HO2S connector and PCM connector D-109. Then go to step 15. If continuity does not exist, go to next step.
  14. Disconnect right rear HO2S sensor connector. Connect jumper wire between right rear HO2S connector terminal No. 1 (component side) and battery positive terminal. Connect second jumper wire between right rear HO2S connector terminal No. 3 (component side) and battery negative terminal. Connect digital voltmeter between right rear HO2S connector terminals No. 2 and 4 (component side). Start engine. When engine is at normal operating temperature, repeatedly rev engine and check right rear HO2S output voltage. Voltage should be 0.6-1.0 volts. If voltage is as specified, replace PCM. Go to next step. If voltage is not as specified, replace right rear HO2S. Go to next step.
  15. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0138 is output, go to step 1 and retry diagnostic procedure. If DTC P0138 is not output, inspection is complete.

Engine coolant temperature is more than 169°F (76°C). Right front HO2S is active. Cumulative Volume Air Flow (VAF) sensor output frequency is 4000 Hz or more.

Repeat These Drive & Stop Steps 3 Or More Times

  1. Drive Conditions
  2. Engine speed is higher than 1500 RPM.
  3. Volumetric efficiency is more than 40 percent.
  4. Vehicle speed is higher than 19 MPH (30 Km/H).
  5. 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.
  6. Stop Conditions
  7. Bring vehicle speed to lower than 1 MPH (1.5 Km/H).

Right rear HO2S signal voltage is 0.078 volt or less for 3 minutes or more after engine starts. Monitoring stops after fuel has been shut off for more than 38 seconds.

  1. Start engine. Using scan tool, check data list item No. 69 (right rear heated oxygen sensor). Warm up engine. After increasing sensor output voltage 0.15 volt or more, when engine is revved, verify right rear HO2S output voltage reduces to 0.15 volt less. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000) . If scan tool readings are not as specified, go to next step.
  2. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0139 is output, go to step 1 and retry diagnostic procedure. If DTC P0139 is not output, inspection is complete.

60 seconds have elapsed from the start of the previous monitoring. Engine coolant temperature is more than 68°F (20°C). Battery voltage is 11-16 volts. One monitor runs each drive cycle while right rear HO2S heater is on. Code will set if heater current of right rear HO2S heater is less than 0.16 amp, or more than 5.0 amps, for 4 seconds.

  1. Turn ignition off. Disconnect right rear HO2S connector. Check right rear HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  2. Measure resistance between right rear HO2S connector terminals No. 1 and 3 (component side). see scheme 22 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 right rear HO2S. Go to step 13.
  3. Turn ignition on. Measure voltage between ground and right rear HO2S connector terminal No. 1 (Red wire). If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
  4. Turn ignition off. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Remove MFI relay. see scheme 4 Check MFI relay connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, repair Red wire between MFI relay and right rear HO2S. Go to step 13.
  5. Turn ignition off. Reconnect right rear HO2S connector. Turn ignition on. Measure voltage between ground and PCM connector D-107 terminal No. 27 (Yellow/Black wire) by backprobing. see scheme 28 If battery voltage exists, go to step 8. If battery voltage does not exist, go to next step.
  6. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  7. Turn ignition off. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. With PCM connector D-107 and right rear HO2S connector disconnected, check continuity between right rear HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 27 (Yellow/Black wire). Continuity should exist. see scheme 28 Then check continuity between ground and right rear HO2S connector terminal No. 3 (Yellow/Black wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Yellow/Black wire. Go to step 13. If continuity is as specified, replace PCM. Go to step 13.
  8. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  9. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. Reconnect PCM connector. Turn ignition on. Measure voltage between ground and right rear HO2S connector terminal No. 1 (Red wire). Battery voltage should exist. Turn ignition off. Remove MFI relay. see scheme 4 Turn ignition on. Measure voltage between ground and MFI relay connector terminals No. 2 and 3. see scheme 26 If battery voltage does not exist at either or both terminals, repair White/Black wire between MFI relay connector and fusible link No. 6 (20-amp) located in engine compartment relay box. Then go to step 13. If battery voltage exists at both terminals, check MFI relay connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. If problem does not exist, replace MFI relay. Go to next step.
  10. Turn ignition off. Check continuity between right rear HO2S connector terminal No. 1 (Red wire) and MFI relay connector terminal No. 1. Continuity should exist. see scheme 22 Then check continuity between ground and right rear HO2S connector terminal No. 1 (Red wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Red wire. Go to step 13. If continuity is as specified, go to next step.
  11. Check intermediate connector between PCM and right rear HO2S. If damaged, repair or replace as necessary. With PCM connector D-107 and right rear HO2S connector disconnected, check continuity between right rear HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 27 (Yellow/Black wire). Continuity should exist. see scheme 28 Then check continuity between ground and right rear HO2S connector terminal No. 3 (Yellow/Black wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Yellow/Black wire. Go to step 13. If continuity is as specified, go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0141 is output, replace PCM. Go to next step. If DTC P0141 is not output, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  13. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0141 is output, retry diagnostic procedure. If DTC P0141 is not output, inspection is complete.

After engine starts, left front HO2S signal is 0.2 volt or less for 3 minutes or more. Engine coolant temperature is more than 180°F (82°C). Engine speed is more than 1200 RPM. Volumetric efficiency is more than 25 percent. Code will set when input voltage supplied to Powertrain Control Module (PCM) interface circuit is more than 4.5 volts when 5 volts are applied to HO2S output line through a resistor. Monitor runs only once during drive cycle for 7 seconds.

  1. Start engine and warm to normal operating temperature. Using scan tool, check data list item No. 11 (left front heated oxygen sensor). When engine is repeatedly revved, left front HO2S output voltage should read 0.6-1.0 volt. When engine is idling, voltage should repeatedly alternate between less than 0.4 volt and more than 0.6 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. With engine running, measure voltage between ground and left front HO2S connector terminal No. 4 (White wire) by backprobing. see scheme 22 With engine speed at 2500 RPM, left front HO2S voltage should alternate between about zero volts and 0.8 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  3. With engine running, measure voltage between ground and PCM connector D-109 terminal No. 71 (White wire) by backprobing. see scheme 28 With engine speed at 2500 RPM, left front HO2S voltage should alternate between about zero volts and 0.8 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 6.
  4. Turn ignition off. Check left front HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, go to next step.
  5. Start engine and warm to normal operating temperature. Using scan tool, check data list item No. 11 (left front heated oxygen sensor). When engine is repeatedly revved, left front HO2S 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 to 1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, replace PCM. Go to step 15.
  6. Turn ignition off. Check left front HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, repair White wire between left front HO2S and PCM connector D-109 terminal No. 71. Go to step 15.
  7. Turn ignition off. Disconnect left front HO2S connector. Check left front HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  8. Check for continuity between ground and left front HO2S connector terminal No. 2 (Black wire). see scheme 22 If continuity exists, go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  10. Disconnect PCM connector D-108 and left front HO2S connector(s). Check continuity in Black wire between left front HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair Black wire. Go to step 15. If continuity exists, replace PCM. Go to step 15.
  11. Check PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  12. Disconnect PCM connector D-108 and left front HO2S connector(s). Check continuity in Black wire between left front HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair Black wire. Go to step 15. If continuity exists, go to next step.
  13. Disconnect right front HO2S connector. see scheme 22 Check continuity between left front HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 71 (White wire). There should be continuity. Check continuity between ground and left front HO2S connector terminal No. 4 (White wire). There should be no continuity. Reconnect PCM connectors. Turn ignition on. Measure voltage at left front HO2S connector terminal 4 (White wire). There should be less than 0.8 volt. If problem exists, repair open, short to ground or short to battery voltage in White wire. Go to step 15. If problem does not exist, go to next step.
  14. Ensure engine is warmed up. Disconnect left front HO2S connector. Connect jumper wire between battery positive terminal and left front HO2S connector terminal No. 1 (component side). Connect jumper wire between battery negative terminal and left front HO2S connector terminal No. 3 (component side). Connect digital voltmeter between left front HO2S connector terminals No. 2 and 4 (component side). Start engine. While repeatedly revving engine, measure left front HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, replace PCM. Go to next step. If voltage is not as specified, replace left front HO2S. Go to next step.
  15. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0152 is output, retry diagnostic procedure. If DTC P0152 is not output, inspection is complete.

Engine coolant temperature is more than 122°F (50°C). Engine speed is 1250-3000 RPM. Volumetric efficiency is 20-60 percent. Intake air 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). Engine is under closed loop air/fuel control and not in idle state. Short term fuel trim is between -30 and 25 percent. More than 3 seconds have elapsed after the above mentioned conditions have been met. Monitor runs 3 times for 12 seconds per drive cycle. Code will set when front HO2S sends alternating lean and rich signals 8 times or less in 12 seconds.

  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 11 (left front heated oxygen sensor). When engine is revved, left front HO2S output voltage should read 0.6-1.0 volt. When engine is idling, left front HO2S output voltage should alternate between less than 0.4 volt and more than 0.6 volt 10 times or more within 10 seconds. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000) . If scan tool readings are not as specified, replace HO2S. Go to next step.
  2. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor pattern. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) under OBD-II DRIVE CYCLES in VERIFYING REPAIRS. Check for DTCs. If DTC P0153 is output, retry diagnostic procedure. If DTC P0153 is not output, inspection is complete.

30 seconds or more have passed since the starting sequence was completed. Engine coolant temperature is higher than 169°F (76°C). Engine speed is higher than 1200 RPM. Volumetric efficiency is higher than 30 percent. Throttle position sensor output voltage is lower than 4 volts. Except while fuel is being shut off. Monitoring time is 30 seconds. Code will set when left front HO2S output voltage does not get across 0.5 volt within about 30 seconds.

  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 59 (left rear heated oxygen sensor). When engine is revved, left rear HO2S output voltage should read 0.6-1.0 volt. If scan tool readings are as specified, go to next step. If scan tool readings are not as specified, refer to DTCs P0157, P0158 or P0159 diagnostic procedures.
  2. Check for exhaust leaks. If exhaust leaks are found, repair as necessary. Then go to step 14. If no exhaust leaks are found, go to next step.
  3. Check the intake system for vacuum leaks. If any vacuum leaks are found, repair as necessary. Then go to step 14. If no vacuum leaks are found, go to next step.
  4. Turn ignition off. Disconnect left front HO2S connector. see scheme 22 Check left front HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  5. Ensure engine is warmed up. Connect jumper wire between battery positive terminal and left front HO2S connector terminal No. 1 (component side). Connect jumper wire between battery negative terminal and left front HO2S connector terminal No. 3 (component side). Connect digital voltmeter between left front HO2S connector terminals No. 2 and 4 (component side). Start engine. While repeatedly revving engine, measure left front HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, replace left front HO2S. Go to step 13.
  6. Turn ignition off. Disconnect fuel injector intermediate connector. see scheme 20 Check fuel injector intermediate connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  7. Measure resistance of left bank injectors at the fuel injector intermediate connector. Measure between fuel injector intermediate connector terminals No. 8 and 2 (cylinder No. 2), terminals No. 8 and 7 (cylinder No. 4) and terminals No. 8 and 5 (cylinder No. 6). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, go to step 10. If resistance is not as specified, go to next step.
  8. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check the left bank injector connector that deviates from the specified value of resistance at step 7. see scheme 19 If connectors are OK, go to next step. If connectors are not OK, repair or replace as necessary. Then go to step 13.
  9. Check the left bank injector terminals (component side) that deviates from the specified value of resistance at step 7). Measure resistance of left bank injectors (component side). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, repair damaged wire between fuel injector intermediate connector and left bank injector connector. Then go to step 13. If resistance is not as specified, replace the injector. Then go to step 13. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES.
  10. Disconnect and check PCM connectors D-108 and D-109 for loose, damaged, or corroded terminals. see scheme 28 If problem exists, repair or replace connector(s). Go to step 13. If problem does not exist, go to next step.
  11. Disconnect left front HO2S connector. see scheme 22 Check continuity between left front HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 71 (White wire). Check continuity between ground and left front HO2S connector terminal No. 4 (White wire). Reconnect PCM connectors. Turn ignition on. Measure voltage at left front HO2S connector terminal 4 (White wire). There should be less than 0.8 volt. If problem exists, repair open, short to ground or short to battery voltage in White wire. Go to step 13. If problem does not exist, go to next step.
  12. Disconnect PCM connector D-107 and fuel injector intermediate connector. see scheme 20 Check continuity between left bank injectors wires and PCM connector D-107. See «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (LEFT BANK)»(ref-135490-S25591382772003050500000). Check continuity between ground and left bank injectors wires. See «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (LEFT BANK)»(ref-135490-S25591382772003050500000). Reconnect PCM connectors. Turn ignition on. Measure voltage at fuel injector intermediate connector. See «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (LEFT BANK)»(ref-135490-S25591382772003050500000). There should be battery voltage. If problem exists, repair open or short to ground suspect wire. Go to step 14. If problem does not exist, go to next step. INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (LEFT BANK) Injector No. & Wire Color Injector Intermediate Connector Terminal No. PCM Connector D-107 Terminal No. Inj. No. 2 (Yellow/Red) (1) No. 2 No. 9 Inj. No. 4 (Orange) (1) No. 7 No. 2 Inj. No. 6 (White/Red) (1) No. 5 No. 25 (1) The terminal referenced to is fuel injector connector terminal No. 2.
  13. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES. If fuel pressure is OK, replace PCM. Then go to next step. If fuel pressure is not as specified, repair as necessary. Go to next step.
  14. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0154 is output, go to step 1 and retry diagnostic procedure. If DTC P0154 is not output, inspection is complete.

60 seconds have elapsed from the start of previous monitoring. Engine coolant temperature is more than 68°F (20°C). Left front HO2S heater is on. Battery voltage is 11-16 volts. Code will set if left front HO2S heater current is less than 0.6 amp, or more than 7.5 amps, for 4 seconds. One monitor runs each drive cycle.

  1. Turn ignition off. Disconnect left front HO2S 4-pin connector. Check left front HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  2. Measure resistance between left front HO2S connector terminals No. 1 and 3 (component side). see scheme 22 Resistance should be 4.5-8.0 ohms at 68°F (20°C). If problem exists, replace left front HO2S. Go to step 12. If problem does not exist, go to next step.
  3. Turn ignition on. Measure voltage between ground and left front HO2S connector terminal No. 1 (Red wire). If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
  4. Turn ignition off. Remove MFI relay. see scheme 4 Check MFI relay connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, repair Red wire between MFI relay and left front HO2S. Go to step 12.
  5. Reconnect left front HO2S connector. Turn ignition on. Measure voltage between ground and PCM connector D-107 terminal No. 3 (Blue wire) by backprobing. see scheme 28 If battery voltage exists, go to step 8. If battery voltage does not exist, go to next step.
  6. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  7. With PCM connector D-107 and left front HO2S connector disconnected, check continuity between left front HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 3 (Blue wire). Continuity should exist. see scheme 22and see scheme 28. Then check continuity between ground and left front HO2S connector terminal No. 3 (Blue wire). Continuity should not exist. If problem exists, repair open or short in Blue wire. Go to step 12. If problem does not exist, replace PCM. Go to step 12.
  8. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  9. Disconnect left front HO2S connector and remove MFI relay. Check continuity between ground and left front HO2S connector terminal No. 1 (Red wire). see scheme 22and see scheme 26. Continuity should not exist. If continuity exists, repair short to ground in Red wire. Go to step 12. If continuity does not exist, go to next step.
  10. With PCM connector D-107 and left front HO2S connector disconnected, check continuity between left front HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 3 (Blue wire). Continuity should exist. see scheme 22and see scheme 28. Then check continuity between ground and left front HO2S connector terminal No. 3 (Blue wire). Continuity should not exist. If problem exists, repair open or short in Blue wire. Go to step 12. If problem does not exist, go to next step.
  11. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0155 is output, replace PCM. Go to next step. If DTC P0155 is not output, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0155 is output, go to step 1 and retry diagnostic procedure. If DTC P0155 is not output, inspection is complete.

30 seconds or more have passed since the starting sequence was completed. Left rear HO2S signal voltage is 0.15 volt or lower. Engine coolant temperature is higher than 169°F (76°C). Engine speed is higher than 1200 RPM. Volumetric efficiency is higher than 25 percent. Volume Air Flow (VAF) sensor output frequency is 100 Hz or more. At least 20 seconds have passed since fuel shut off control was cancelled. Monitoring time is 10 seconds. Left front HO2S outputs 0.5 volt or more. Left rear HO2S signal voltage is 0.078 volt or less for 3 minutes or more after engine starts. Code will set when making air/fuel ratio 15 percent richer for 10 seconds does not increase rear HO2S output voltage beyond 0.15 volt.

  1. Start engine. Using scan tool, check data list item No. 59 (left rear heated oxygen sensor). When engine is revved, left rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Disconnect left rear HO2S sensor connector. Connect jumper wire between left rear HO2S connector terminal No. 1 (component side) and battery positive terminal. Connect second jumper wire between left rear HO2S connector terminal No. 3 (component side) and battery negative terminal. Connect digital voltmeter between left rear HO2S connector terminals No. 2 and 4 (component side). Start engine. When engine is at normal operating temperature, repeatedly rev engine and check left rear HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, replace left rear HO2S. Go to step 5.
  3. Turn ignition off. Check left rear HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 5. If problem does not exist, go to next step.
  4. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. Disconnect left rear HO2S connector and PCM connector D-109. Check for continuity between ground and left rear HO2S connector terminal No. 4 (White wire). see scheme 22 If continuity exists, repair short circuit in White wire between left rear HO2S connector and PCM connector D-109. Then go to next step. If continuity does not exist, replace PCM. Then go to next step.
  5. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0157 is output, retry diagnostic procedure. If DTC P0157 is not output, inspection is complete.

Left rear HO2S signal voltage is 0.15 volt or less for 3 minutes or more after 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 25 percent. Code will set when input voltage supplied to Powertrain Control Module (PCM) interface circuit is more than 4.5 volts when 5 volts is applied to rear HO2S output line through a resistor. Monitor is run once per drive cycle for 7 seconds.

  1. Start engine. Using scan tool, check data list item No. 59 (left rear heated oxygen sensor). When engine is revved, left rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Measure voltage between ground and left rear HO2S connector terminal No. 4 (White wire) by backprobing. see scheme 22 When engine is revved, left rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  3. Measure voltage between ground and PCM connector D-109 terminal No. 73 (White wire) by backprobing. see scheme 28 When engine RPM is held at 2500 RPM while engine is warming up, left rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, go to next step. If voltage is not as specified, go to step 6.
  4. Turn ignition off. Check left rear HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, go to next step.
  5. Start engine. Using scan tool, check data list item No. 59 (left rear heated oxygen sensor). When engine is revved, left rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, replace PCM. Go to step 15.
  6. Turn ignition off. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. Check left rear HO2S connector and PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s). Go to step 15. If problem does not exist, repair White wire between left rear HO2S connector terminal No. 4 and PCM connector D-109 terminal No. 73. see scheme 22and see scheme 28. Then go to step 15.
  7. Turn ignition off. Disconnect left rear HO2S. Check left rear HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  8. Check for continuity between ground and left rear HO2S connector terminal No. 2 (Black wire). see scheme 22 If continuity exists, go to step 11. If continuity does not exist, go to next step.
  9. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  10. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. Check continuity between ground and Black wire between left rear HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If continuity does not exist, repair open in Black wire. Go to step 15. If continuity exists, replace PCM. Go to step 15.
  11. Check PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 15. If problem does not exist, go to next step.
  12. Check for damage or open in Black wire between left rear HO2S connector terminal No. 2 and PCM connector D-108 terminal No. 57. see scheme 22and see scheme 28. If problem exists, repair Black wire. Go to step 15. If problem does not exist, go to next step.
  13. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. Disconnect left rear HO2S connector and PCM connector D-109. Check for continuity between ground and left rear HO2S connector terminal No. 4 (White wire). see scheme 22and see scheme 28. If continuity exists, repair short circuit in White wire between left rear HO2S connector and PCM connector D-109 terminal No. 73. Then go to step 15. If continuity does not exist, go to next step.
  14. Disconnect left rear HO2S sensor connector. Connect jumper wire between left rear HO2S connector terminal No. 1 (component side) and battery positive terminal. Connect second jumper wire between left rear HO2S connector terminal No. 3 (component side) and battery negative terminal. Connect digital voltmeter between left rear HO2S connector terminals No. 2 and 4 (component side). Start engine. When engine is at normal operating temperature, repeatedly rev engine and check left rear HO2S output voltage. Voltage should be 0.6-1.0 volt. If voltage is as specified, replace PCM. Go to next step. If voltage is not as specified, replace left rear HO2S. Go to next step.
  15. Test drive vehicle following OBD-II drive cycle Heated Oxygen Sensor Monitor and Other Monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) and «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0158 is output, go to step 1 and retry diagnostic procedure. If DTC P0158 is not output, inspection is complete.

Engine coolant temperature is more than 169°F (76°C). Right front HO2S is active. Cumulative Volume Air Flow (VAF) sensor output frequency is 4000 Hz or more.

Repeat These Drive & Stop Steps 3 Or More Times

  1. Drive Conditions
  2. Engine speed is higher than 1500 RPM.
  3. Volumetric efficiency is more than 40 percent.
  4. Vehicle speed is higher than 19 MPH (30 Km/H).
  5. 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.
  6. Stop Conditions
  7. Bring vehicle speed to lower than 1 MPH (1.5 Km/H).

Left rear HO2S signal voltage is 0.078 volt or less for 3 minutes or more after engine starts. Monitoring stops after fuel has been shut off for more than 38 seconds.

  1. Start engine. Using scan tool, check data list item No. 59 (left rear heated oxygen sensor). Warm up engine. After increasing sensor output voltage 0.15 volt or more, when engine is revved, verify left rear HO2S output voltage reduces to 0.15 volt less. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000) . If scan tool readings are not as specified, go to next step.
  2. Test drive vehicle following OBD-II drive cycle heated oxygen sensor monitor patterns. See «HEATED OXYGEN SENSOR MONITOR»(ref-135490-S21479375872002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0159 is output, go to step 1 and retry diagnostic procedure. If DTC P0159 is not output, inspection is complete.

Sixty seconds have elapsed from the start of the previous monitoring. Engine coolant temperature is more than 68°F (20°C). Battery voltage is 11-16 volts. One monitor runs each drive cycle while left rear HO2S heater is on. Code will set if heater current of left rear HO2S heater is less than 0.16 amp, or more than 5.0 amps, for 4 seconds.

  1. Turn ignition off. Disconnect left rear HO2S connector. Check left rear HO2S connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  2. Measure resistance between left rear HO2S connector terminals No. 1 and 3 (component side). see scheme 22 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 left rear HO2S. Go to step 13.
  3. Turn ignition on. Measure voltage between ground and left rear HO2S connector terminal No. 1 (Red wire). If battery voltage exists, go to step 5. If battery voltage does not exist, go to next step.
  4. Turn ignition off. Check intermediate connectors between MFI relay, PCM and left rear HO2S. If damaged, repair or replace as necessary. Remove MFI relay. see scheme 4 Check MFI relay connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, repair Red wire between MFI relay and left rear HO2S. Go to step 13.
  5. Turn ignition off. Reconnect left rear HO2S connector. Turn ignition on. Measure voltage between ground and PCM connector D-107 terminal No. 26 (Black/Blue wire) by backprobing. see scheme 28 If battery voltage exists, go to step 8. If battery voltage does not exist, go to next step.
  6. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  7. Turn ignition off. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. With PCM connector D-107 and left rear HO2S connector disconnected, check continuity between left rear HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 26 (Black/Blue wire). Continuity should exist. see scheme 28 Then check continuity between ground and left rear HO2S connector terminal No. 3 (Black/Blue wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Black/Blue wire. Go to step 13. If continuity is as specified, replace PCM. Go to step 13.
  8. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 13. If problem does not exist, go to next step.
  9. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. Reconnect PCM connector. Turn ignition on. Measure voltage between ground and left rear HO2S connector terminal No. 1 (Red wire). Battery voltage should exist. Turn ignition off. Remove MFI relay. see scheme 4 Turn ignition on. Measure voltage between ground and MFI relay connector terminals No. 2 and 3. see scheme 26 If battery voltage does not exist at either or both terminals, repair White/Black wire between MFI relay connector and fusible link No. 6 (20-amp) located in engine compartment relay box. Then go to step 13. If battery voltage exists at both terminals, check MFI relay connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. If problem does not exist, replace MFI relay. Go to next step.
  10. Turn ignition off. Check continuity between left rear HO2S connector terminal No. 1 (Red wire) and MFI relay connector terminal No. 1. Continuity should exist. see scheme 22 Then check continuity between ground and left rear HO2S connector terminal No. 1 (Red wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Red wire. Go to step 13. If continuity is as specified, go to next step.
  11. Check intermediate connector between PCM and left rear HO2S. If damaged, repair or replace as necessary. With PCM connector D-107 and left rear HO2S connector disconnected, check continuity between left rear HO2S connector terminal No. 3 and PCM connector D-107 terminal No. 26 (Black/Blue wire). Continuity should exist. see scheme 28 Then check continuity between ground and left rear HO2S connector terminal No. 3 (Black/Blue wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Black/Blue wire. Go to step 13. If continuity is as specified, go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0161 is output, replace PCM. Go to next step. If DTC P0161 is not output, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  13. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0161 is output, go to step 1, and retry diagnostic procedure. If DTC P0161 is not output, inspection is complete.
  1. Engine coolant temperature is lower than 212°F (100°C) when engine is started. Intake air temperature is lower 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 Air Flow (VAF) sensor output frequency is 100 Hz or more. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 7.4 percent for 5 seconds.
  2. Engine coolant temperature is lower than 212°F (100°C) when engine is started. Intake air temperature is lower 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 100 Hz. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 12.5 percent for 5 seconds.
  3. Engine coolant temperature is higher than 212°F (100°C) when engine is started. Intake air temperature is higher 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 100 Hz or more. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 17.6 percent for 5 seconds.
  4. Engine coolant temperature is higher than 212°F (100°C) when engine is started. Intake air temperature is higher 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 100 Hz or less. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 22.3 percent for 5 seconds.
  5. Engine coolant temperature is more than 171°F (77°C). Engine is in closed loop air/fuel control. Code will set if long-term fuel trim has continued to be 12.5 percent or short-term fuel trim has continued to be more than 25.5 percent for 5 seconds.
  1. Check exhaust system for leaks. If problem exists, repair exhaust leak as necessary. Go to step 17. If problem does not exist, go to next step.
  2. Check intake system for vacuum leaks. If problem exists, repair vacuum leak as necessary. Go to step 17. If problem does not exist, go to next step.
  3. Start engine and warm up to normal operating temperature. Using scan tool, check data list item No. 12 (volume airflow). At idle, VAF reading should be 17-46 Hz. At 2500 RPM, VAF reading should be 63-103 Hz. If VAF reading is within specifications, go to next step. If reading is not within specifications, check VAF sensor circuit. See «DTC P0101: VOLUME AIRFLOW (VAF) CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S36732530322003050100000) and «DTC P0102: VOLUME AIRFLOW (VAF) CIRCUIT LOW INPUT»(ref-135490-S00583892922002022200000).
  4. Using scan tool, check data list item No. 13 (intake air temperature). Intake air temperature, as measured with a thermometer, and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check air temperature circuit. See «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S26617426552002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S33058689332003050100000) and «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S14263395492003050100000).
  5. Using scan tool, check data list item No. 21 (engine coolant temperature). Engine coolant temperature and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check engine coolant temperature circuit. See «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S10391712222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S38663755262003050200000) and «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S10919985952003050200000).
  6. Using scan tool, check data list item No. 25 (barometric pressure). Compare reading with expected value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool reading is as specified, go to next step. If scan tool reading is not as specified, check barometric pressure circuit. See «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S12292240392002022200000) and «DTC P0107: BAROMETRIC PRESSURE SENSOR CIRCUIT LOW INPUT»(ref-135490-S26298383172003050100000) and «DTC P0108: BAROMETRIC PRESSURE SENSOR CIRCUIT HIGH INPUT»(ref-135490-S29964437272003050100000).
  7. Turn ignition off. Disconnect fuel injector intermediate connector. see scheme 20 Check fuel injector intermediate connector for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  8. Measure resistance of right bank injectors at the fuel injector intermediate connector. Measure between fuel injector intermediate connector terminals No. 8 and 3 (cylinder No. 1), terminals No. 8 and 1 (cylinder No. 3) and terminals No. 8 and 6 (cylinder No. 5). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is not as specified, go to next step. If resistance is as specified, go to step 11.
  9. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check the right bank injector connector that deviates from the specified value of resistance at step 8. see scheme 19 If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 16.
  10. Measure resistance of right bank injectors (component side) that deviates from the specified value of resistance at step 8. Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, repair damaged wire between fuel injector intermediate connector and right bank injector connector. Then go to step 16. If resistance is not as specified, replace the suspect fuel injector(s). Go to step 16.
  11. Check PCM connector D-107 for loose, damaged, or corroded terminals. see scheme 28 If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  12. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check continuity between right bank fuel injector connector terminals No. 2 and PCM connector D-107. see scheme 19and see scheme 28 and «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (RIGHT BANK)»(ref-135490-S26709373942003050200000) for terminal identification. If continuity is as specified, go to next step. If continuity is not as specified, repair appropriate wire between right bank fuel injector connector terminals No. 2 and PCM connector D-107. Go to step 16.
  13. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. At idle, fuel pressure should be 39 psi (270 kPa) with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) with fuel pressure regulator vacuum line disconnected. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, repair as necessary. Go to step 16.
  14. Check for fuel contamination. If fuel is okay, go to next step. If problem exists, replace fuel. Go to step 16.
  15. Replace right bank fuel injectors. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0171 is output, replace PCM. Go to step 17. If DTC P0171 is not output, inspection is complete.
  16. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Then go to next step.
  17. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0171 is output, go to step 1, and retry diagnostic procedure. If DTC P0171 is not output, inspection is complete.
  1. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Air Flow (VAF) sensor output frequency is 100 Hz or more. Code will set if long-term fuel trim continues to be less than -12.5 percent for 5 seconds or short-term fuel trim continues to be less than -7.4 percent, for 5 seconds.
  2. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Air Flow (VAF) sensor output frequency is 100 Hz or less. Code will set if long-term fuel trim continues to be less than -12.5 percent for 5 seconds or short-term fuel trim continues to be less than -12.5 percent, for 5 seconds.
  3. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Code will set if long-term fuel trim has continued to be -12.5 percent for 5 seconds or short-term fuel trim has continued to -30.0 percent, for 5 seconds.
  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 12 (volume airflow sensor). Scan tool should read between 17 and 46 Hz at idle. When engine is revved to 2500 RPM, frequency should increase to between 63 and 103 HZ. If scan tool reads as specified, go to next step. If scan tool does not read as specified, turn engine off and check VAF sensor circuit. See «DTC P0101: VOLUME AIRFLOW (VAF) CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S36732530322003050100000) and «DTC P0102: VOLUME AIRFLOW (VAF) CIRCUIT LOW INPUT»(ref-135490-S00583892922002022200000).
  2. Using scan tool, check data list item No. 13 (intake air temperature). Intake air temperature, as measured with a thermometer, and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check air temperature circuit. See «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S26617426552002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S33058689332003050100000) and «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S14263395492003050100000).
  3. Using scan tool, check data list item No. 21 (engine coolant temperature). Engine coolant temperature and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check engine coolant temperature circuit. See «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S10391712222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S38663755262003050200000) and «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S10919985952003050200000).
  4. Using scan tool, check data list item No. 25 (barometric pressure). Compare reading with expected value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool reading is as specified, go to next step. If scan tool reading is not as specified, check barometric pressure circuit. See «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S12292240392002022200000) and «DTC P0107: BAROMETRIC PRESSURE SENSOR CIRCUIT LOW INPUT»(ref-135490-S26298383172003050100000) and «DTC P0108: BAROMETRIC PRESSURE SENSOR CIRCUIT HIGH INPUT»(ref-135490-S29964437272003050100000).
  5. Turn ignition off. Disconnect fuel injector intermediate connector. see scheme 20 Check fuel injector intermediate connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  6. Measure resistance of right bank injectors at the fuel injector intermediate connector. Measure between fuel injector intermediate connector terminals No. 8 and 3 (cylinder No. 1), terminals No. 8 and 1 (cylinder No. 3) and terminals No. 8 and 6 (cylinder No. 5). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, go to step 8. If resistance is not as specified, go to next step.
  7. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check the right bank injector connector that deviates from the specified value of resistance at step 6). see scheme 19 Measure resistance of right bank injectors (component side). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, repair damaged wire between fuel injector intermediate connector and right bank injector connector. Then go to step 10. If resistance is not as specified, replace the fuel injector. Go to step 10.
  8. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. At idle, fuel pressure should be 39 psi (270 kPa) with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) with fuel pressure regulator vacuum line disconnected. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, repair as necessary. Go to step 11.
  9. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Replace right bank fuel injectors. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0172 is output, replace PCM. Go to step 11. If DTC P0172 is not output, inspection is complete.
  10. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Then go to next step.
  11. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0172 is output, go to step 1, and retry diagnostic procedure. If DTC P0172 is not output, inspection is complete.
  1. Engine coolant temperature is lower than 212°F (100°C) when engine is started. Intake air temperature is lower 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 Air Flow (VAF) sensor output frequency is 100 Hz or more. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 7.4 percent for 5 seconds.
  2. Engine coolant temperature is lower than 212°F (100°C) when engine is started. Intake air temperature is lower 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 100 Hz. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 12.5 percent for 5 seconds.
  3. Engine coolant temperature is higher than 212°F (100°C) when engine is started. Intake air temperature is higher 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 100 Hz or more. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 17.6 percent for 5 seconds.
  4. Engine coolant temperature is higher than 212°F (100°C) when engine is started. Intake air temperature is higher 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 100 Hz or less. Code will set if long-term fuel trim continues to be more than 12.5 percent for 5 seconds or short-term fuel trim continues to be more than 22.3 percent for 5 seconds.
  5. Engine coolant temperature is more than 171°F (77°C). Engine is in closed loop air/fuel control. Code will set if long-term fuel trim has continued to be 12.5 percent or short-term fuel trim has continued to be more than 25.5 percent for 5 seconds.
  1. Check exhaust system for leaks. If problem exists, repair exhaust leak as necessary. Go to step 17. If problem does not exist, go to next step.
  2. Check intake system for vacuum leaks. If problem exists, repair vacuum leak as necessary. Go to step 17. If problem does not exist, go to next step.
  3. Start engine and warm up to normal operating temperature. Using scan tool, check data list item No. 12 (volume airflow). At idle, VAF reading should be 17-46 Hz. At 2500 RPM, VAF reading should be 63-103 Hz. If VAF reading is within specifications, go to next step. If reading is not within specifications, check VAF sensor circuit. See «DTC P0101: VOLUME AIRFLOW (VAF) CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S36732530322003050100000) and «DTC P0102: VOLUME AIRFLOW (VAF) CIRCUIT LOW INPUT»(ref-135490-S00583892922002022200000).
  4. Using scan tool, check data list item No. 13 (intake air temperature). Intake air temperature, as measured with a thermometer, and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check air temperature circuit. See «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S26617426552002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S33058689332003050100000) and «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S14263395492003050100000).
  5. Using scan tool, check data list item No. 21 (engine coolant temperature). Engine coolant temperature and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check engine coolant temperature circuit. See «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S10391712222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S38663755262003050200000) and «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S10919985952003050200000).
  6. Using scan tool, check data list item No. 25 (barometric pressure). Compare reading with expected value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool reading is as specified, go to next step. If scan tool reading is not as specified, check barometric pressure circuit. See «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S12292240392002022200000) and «DTC P0107: BAROMETRIC PRESSURE SENSOR CIRCUIT LOW INPUT»(ref-135490-S26298383172003050100000) and «DTC P0108: BAROMETRIC PRESSURE SENSOR CIRCUIT HIGH INPUT»(ref-135490-S29964437272003050100000).
  7. Turn ignition off. Disconnect fuel injector intermediate connector. see scheme 20 Check fuel injector intermediate connector for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  8. Measure resistance of left bank injectors at the fuel injector intermediate connector. Measure between fuel injector intermediate connector terminals No. 8 and 2 (cylinder No. 2), terminals No. 8 and 7 (cylinder No. 4) and terminals No. 8 and 5 (cylinder No. 6). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is not as specified, go to next step. If resistance is as specified, go to step 11.
  9. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check the left bank injector connector that deviates from the specified value of resistance at step 8). see scheme 19 If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 16.
  10. Measure resistance of left bank injectors (component side) that deviates from the specified value of resistance at step 8). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, repair damaged wire between fuel injector intermediate connector and left bank injector connector. Go to step 16. If resistance is not as specified, replace the injector. Go to step 16.
  11. Check PCM connector D-107 for loose, damaged, or corroded terminals. see scheme 28 If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  12. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check continuity between left bank fuel injector connector terminals No. 2 and PCM connector D-107. see scheme 19and see scheme 28 and «INJECTOR CONNECTOR TO INJECTOR INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS (LEFT BANK)»(ref-135490-S25591382772003050500000) for terminal identification. If continuity is as specified, go to next step. If continuity is not as specified, repair appropriate wire. Go to step 16.
  13. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. At idle, fuel pressure should be 39 psi (270 kPa) with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) with fuel pressure regulator vacuum line disconnected. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, repair as necessary. Go to step 16.
  14. Check for fuel contamination. If fuel is okay, go to next step. If problem exists, replace fuel. Go to step 16.
  15. Replace left bank fuel injectors. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0174 is output, replace PCM. Go to step 17. If DTC P0174 is not output, inspection is complete.
  16. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Then go to next step.
  17. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0174 is output, go to step 1, and retry diagnostic procedure. If DTC P0174 is not output, inspection is complete.
  1. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Air Flow (VAF) sensor output frequency is 100 Hz or more. Code will set if long-term fuel trim continues to be less than -12.5 percent for 5 seconds or short-term fuel trim continues to be less than -7.4 percent, for 5 seconds.
  2. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Volume Air Flow (VAF) sensor output frequency is 100 Hz or less. Code will set if long-term fuel trim continues to be less than -12.5 percent for 5 seconds or short-term fuel trim continues to be less than -12.5 percent, for 5 seconds.
  3. Engine is in closed loop air/fuel control. Engine coolant temperature is more than 171°F (77°C). Code will set if long-term fuel trim has continued to be -12.5 percent for 5 seconds or short-term fuel trim has continued to -30.0 percent, for 5 seconds.
  1. Start and warm engine to normal operating temperature. Using scan tool, check data list item No. 12 (volume airflow sensor). Scan tool should read between 17 and 46 Hz at idle. When engine is revved to 2500 RPM, frequency should increase to between 63 and 103 HZ. If scan tool reads as specified, go to next step. If scan tool does not read as specified, turn engine off and check VAF sensor circuit. See «DTC P0101: VOLUME AIRFLOW (VAF) CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S36732530322003050100000) and «DTC P0102: VOLUME AIRFLOW (VAF) CIRCUIT LOW INPUT»(ref-135490-S00583892922002022200000).
  2. Using scan tool, check data list item No. 13 (intake air temperature). Intake air temperature, as measured with a thermometer, and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check air temperature circuit. See «DTC P0111: INTAKE AIR TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S26617426552002022200000) and «DTC P0112: INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S33058689332003050100000) and «DTC P0113: INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S14263395492003050100000).
  3. Using scan tool, check data list item No. 21 (engine coolant temperature). Engine coolant temperature and temperature displayed on scan tool should be within 10 percent of each other. If temperature is as specified, go to next step. If temperature is not as specified, check engine coolant temperature circuit. See «DTC P0116: ENGINE COOLANT TEMPERATURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S10391712222002022200000) and «DTC P0117: ENGINE COOLANT TEMPERATURE CIRCUIT LOW INPUT»(ref-135490-S38663755262003050200000) and «DTC P0118: ENGINE COOLANT TEMPERATURE CIRCUIT HIGH INPUT»(ref-135490-S10919985952003050200000).
  4. Using scan tool, check data list item No. 25 (barometric pressure). Compare reading with expected value. See «BAROMETRIC PRESSURE SENSOR SPECIFICATIONS»(ref-135490-S37867632062002022200000). If scan tool reading is as specified, go to next step. If scan tool reading is not as specified, check barometric pressure circuit. See «DTC P0106: BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE PROBLEM»(ref-135490-S12292240392002022200000) and «DTC P0107: BAROMETRIC PRESSURE SENSOR CIRCUIT LOW INPUT»(ref-135490-S26298383172003050100000) and «DTC P0108: BAROMETRIC PRESSURE SENSOR CIRCUIT HIGH INPUT»(ref-135490-S29964437272003050100000).
  5. Turn ignition off. Disconnect fuel injector intermediate connector. see scheme 20 Check fuel injector intermediate connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  6. Measure resistance of left bank injectors at the fuel injector intermediate connector. Measure between fuel injector intermediate connector terminals No. 8 and 2 (cylinder No. 2), terminals No. 8 and 7 (cylinder No. 4) and terminals No. 8 and 5 (cylinder No. 6). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, go to step 8. If resistance is not as specified, go to next step.
  7. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Check the left bank injector connector that deviates from the specified value of resistance at step 6. see scheme 19 Measure resistance of left bank injectors (component side). Resistance should be between 13-16 ohms at 68°F (20°C). If resistance is as specified, repair damaged wire between fuel injector intermediate connector and left bank injector connector. Go to step 10. If resistance is not as specified, replace the injector. Go to step 10.
  8. Check fuel pressure. See «FUEL PRESSURE»(ref-135483-S11745319792002022200000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. At idle, fuel pressure should be 39 psi (270 kPa) with fuel pressure regulator vacuum line connected and 47-50 psi (330-350 kPa) with fuel pressure regulator vacuum line disconnected. If fuel pressure is as specified, go to next step. If fuel pressure is not as specified, repair as necessary. Go to step 11.
  9. Remove the intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Replace left bank fuel injectors. Reinstall intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0175 is output, replace PCM. Go to step 11. If DTC P0175 is not output, inspection is complete.
  10. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Then go to next step.
  11. Test drive vehicle following OBD-II drive cycle fuel trim monitor pattern. See «FUEL TRIM MONITOR»(ref-135490-S03436696692002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0175 is output, go to step 1, and retry diagnostic procedure. If DTC P0175 is not output, inspection is complete.

Engine coolant temperature-intake air temperature is lower than 9°F (5°C) when engine is started. Engine coolant temperature is between 14°F (10°C) and 97°F (36°C) when engine is started. Engine coolant temperature is higher than 140°F (60°C). Maximum vehicle speed is higher than 17 MPH (30 Km/h) after the starting sequence has been completed. Code will set if fuel temperature-engine coolant temperature is 27°F (15°C) or more when engine is started.

  1. Turn ignition on. Using scan tool, check data list item No. 4A (fuel temperature sensor). Air temperature, as measured with a thermometer, and fuel temperature displayed on scan tool should be within 10 percent of each other. If temperature is not as specified, go to next step. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Disconnect fuel temperature sensor 3-pin connector. see scheme 18 Check fuel temperature sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  3. Measure resistance between fuel temperature sensor terminals No. 2 and 3 (component side). Resistance should be between 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 continuity between ground and fuel temperature sensor 3-pin connector terminal No. 2 (Black wire). If continuity exists, go to next step. If continuity does not exist, check intermediate 8-pin connector F-07 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07 is OK, repair open in wire between fuel temperature sensor 3-pin connector terminal No. 2 (Black wire) and ground. Then go to step 12.
  5. Turn ignition on. Measure voltage between ground and fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire). There should be between 4.5-4.9 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 10.
  6. Reconnect fuel temperature sensor 3-pin connector. Turn ignition on. Measure voltage between ground and PCM connector D-108 terminal No. 51 (Light Green/Red wire) by backprobing. see scheme 28 See «FUEL TEMPERATURE SENSOR VOLTAGE SPECIFICATIONS»(ref-135490-S33516228482003050600000). If voltage is as specified, go to next step. If voltage is not as specified, go to step 8. FUEL TEMPERATURE SENSOR VOLTAGE SPECIFICATIONS Volts Fuel Temperature °F (°C) 2.7 - 3.1 32 (0) 2.1 - 2.5 68 (20) 1.6 - 2.0 104 (40) 0.8 - 1.2 176 (80)
  7. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair Light Green/Red wire between fuel temperature sensor 3-pin connector terminal No. 3 and PCM connector D-108 terminal No. 51. Then go to step 12.
  8. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  9. Disconnect fuel temperature sensor 3-pin connector. With PCM D-108 connector disconnected, check continuity between ground and fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire). If there is continuity, check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair short to ground in wire between fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire) and PCM connector D-108 terminal No. 51. Then go to step 12. If there is no continuity, replace PCM, and go to step 12.
  10. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. Also check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair or replace connector(s). Go to step 12. If problem does not exist, go to next step.
  11. Disconnect fuel temperature sensor 3-pin connector. With PCM D-108 connector disconnected, check continuity between ground and fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire). If there is continuity, repair short to ground in wire between fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire) and PCM connector D-108 terminal No. 51. Then go to next step. If there is no continuity, replace PCM, and go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0181 is output, go to step 1, and retry diagnostic procedure. If DTC P0181 is not output, inspection is complete.

2 seconds or more have passed since the starting sequence was completed. Code will set when sensor output voltage has continued to be 0.1 volt or lower for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 4A (fuel temperature sensor). Air temperature, as measured with a thermometer, and fuel temperature displayed on scan tool should be within 10 percent of each other. If temperature is not as specified, go to next step. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Measure resistance between fuel temperature sensor terminals No. 2 and 3 (component side). Resistance should be between 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 PCM connector D-108 and fuel temperature sensor 3-pin connector. see scheme 18and see scheme 28. Check connectors for loose, damaged, or corroded terminals. If problem exists, repair or replace connectors. Go to step 5. If problem does not exist, go to next step.
  4. With fuel temperature sensor 3-pin connector and PCM D-108 connector disconnected, check continuity between ground and fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire). If there is continuity, check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair short to ground in wire between fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire) and PCM connector D-108 terminal No. 51. Then go to next step. If there is no continuity, replace PCM, and go to next step.
  5. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0182 is output, go to step 1, and retry diagnostic procedure. If DTC P0182 is not output, inspection is complete.

2 seconds or more have passed since the starting sequence was completed. Code will set when sensor output voltage has continued to be 4.6 volts or higher for 2 seconds.

  1. Turn ignition on. Using scan tool, check data list item No. 4A (fuel temperature sensor). Air temperature, as measured with a thermometer, and fuel temperature displayed on scan tool should be within 10 percent of each other. If temperature is not as specified, go to next step. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool readings are not as specified, go to next step.
  2. Disconnect fuel temperature sensor 3-pin connector. see scheme 18 Check connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  3. Measure resistance between fuel temperature sensor terminals No. 2 and 3 (component side). Resistance should be between 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 on. Measure voltage between ground and fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire). There should be between 4.5-4.9 volts. If voltage is as specified, go to step 8. If voltage is not as specified, go to next step.
  5. Turn ignition on. Disconnect fuel temperature sensor 3-pin connector. Measure voltage between ground and PCM connector D-108 terminal No. 51 (Light Green/Red wire) by backprobing. see scheme 28 There should be between 4.5-4.9 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  6. Disconnect PCM connector D-108. Check connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair open circuit in wire between fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire) and PCM connector D-108 terminal No. 51. Then go to step 11.
  7. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, replace PCM. Go to step 11.
  8. Check continuity between ground and fuel temperature sensor 3-pin connector terminal No. 2 (Black wire). If continuity exists, go to next step. If continuity does not exist, check intermediate 8-pin connector F-07 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07 is OK, repair open in wire between fuel temperature sensor 3-pin connector terminal No. 2 (Black wire) and ground. Then go to step 11.
  9. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 11. If problem does not exist, go to next step.
  10. Check continuity between PCM connector D-108 terminal No. 51 (Light Green/Red wire) and fuel temperature sensor 3-pin connector terminal No. 3. If continuity exists, replace PCM. Go to next step. If continuity does not exist, check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair open circuit in wire between fuel temperature sensor 3-pin connector terminal No. 3 (Light Green/Red wire) and PCM connector D-108 terminal No. 51. Then go to next step.
  11. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0183 is output, go to step 1, and retry diagnostic procedure. If DTC P0183 is not output, inspection is complete.

Engine speed is less than 1000 RPM. Throttle Position (TP) sensor output voltage is less than 1.16 volts. Code will set if fuel injector coil surge voltage (system voltage plus 2 volts) has not been detected for 2 seconds.

  1. Warm engine to normal operating temperature and let idle. Set scan tool to actuator testing mode for injectors. Using scan tool, turn each fuel injector off, then on. As each fuel injector is turned off, there should be an idle speed drop and rough idle. Idle should improve when fuel injector is turned back on. If fuel injectors perform as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If any fuel injector does not perform as specified, go to next step.
  2. Disconnect fuel injector 8-pin intermediate connector B-44. Check fuel injector intermediate connector B-44 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 18. If problem does not exist, go to next step.
  3. Check resistance of each fuel injector at fuel injector intermediate connector B-44. see scheme 20and «FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS»(ref-135490-S14752298562003050700000). Resistance should be 13-16 ohms at 68°F (20°C). If resistance is as specified, go to step 6. If resistance is not as specified, go to next step. FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS Fuel Injector No. & Wire Color (2) Injector Intermediate Connector B-44 Terminal No. PCM Connector D-107 Terminal No. Inj. No. 1 (Yellow/Blue) No. 3 (1) No. 1 Inj. No. 2 (Yellow/Red) No. 2 (1) No. 9 Inj. No. 3 (Light Green) No. 1 (1) No. 24 Inj. No. 4 (Orange) No. 7 (1) No. 2 Inj. No. 5 (Blue) No. 6 (1) No. 10 Inj. No. 6 (White/Red) No. 5 (1) No. 25 (1) All Fuel Injector resistance measurements share intermediate connector B-44 terminal No. 8 (Red wire between F.I. connectors terminal No. 1 and MFI relay terminal No. 1). (2) Circuit from F.I. connectors terminal No. 2 through intermediate connector B-44 to PCM connector D-107. These terminals connect the PCM to fuel injector.
  4. Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Disconnect connector to fuel injector. Check fuel injector connector for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  5. Check continuity between fuel injector intermediate connector B-44 terminal No. 8 (Red wire) and each fuel injector connector terminal No.1. If continuity exists, replace the fuel injector. Go to step 17. If continuity does not exist, repair open circuit in Red wire between fuel injector intermediate connector B-44 terminal No. 8 and suspect fuel injector connector(s). Go to step 17.
  6. Turn ignition on. Measure voltage between ground and fuel injector intermediate connector B-44 terminal No. 8 (Red wire). If battery voltage exists, go to step 8. If battery voltage does not exist, go to next step.
  7. Turn ignition off. Check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 18. If problem does not exist, repair open in Red wire between MFI relay terminal No. 1 and fuel injector intermediate connector B-44 terminal No. 8. Go to step 18.
  8. Disconnect PCM connector D-107. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 18. If problem does not exist, go to next step.
  9. With fuel injector intermediate connector B-44 and PCM connector D-107 still disconnected, check continuity between fuel injector intermediate connector B-44 and PCM connector D-107. See «FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS»(ref-135490-S14752298562003050700000), see scheme 20 and see scheme 28 for connector terminal identification. There should be continuity. Then, for each fuel injector circuit checked above, check continuity between ground and fuel injector intermediate connector B-44. There should be no continuity. If problem exists, repair appropriate wire. Go to step 18. If problem does not exist, go to next step.
  10. Reconnect PCM connector D-107. Connect Test Harness Special Tool (MB991474) between fuel injector intermediate connector B-44 halves. Connect lab scope probe to appropriate clip on test harness special tool. Start engine and check fuel injector waveforms. See «FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS»(ref-135490-S14752298562003050700000), see scheme 20 and see scheme 28 for connector terminal identification. Run engine at idle. Compare waveform with normal pattern. (Scheme 38) Turn engine off. If waveform is normal, go to step 13. If waveform is not normal, go to next step.
  11. Disconnect fuel injector intermediate connector B-44. Remove Test Harness Special Tool (MB991474). Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Disconnect fuel injector connectors. Check fuel injector connector for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  12. Check continuity between fuel injector intermediate connector B-44 terminal No. 8 (Red wire) and each fuel injector connector terminal No. 1. There should be continuity. Then, check continuity between fuel injector intermediate connector B-44 and each fuel injectors connectors terminal No. 2. See «FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS»(ref-135490-S14752298562003050700000) for connector terminal identification. There should be continuity. Then, check continuity between ground and each fuel injector connector terminal No. 1 and 2. There should be no continuity. If continuity is not as specified, repair or replace circuit wire between fuel injector intermediate connector B-44 and suspect fuel injector connector(s). Go to step 17. If continuity is as specified, replace PCM. Go to step 17.
  13. Disconnect fuel injector intermediate connector B-44. Remove Test Harness Special Tool (MB991474). Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Disconnect fuel injector connectors. Check fuel injector connector for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair or replace connector. Go to step 17.
  14. Remove MFI relay from engine compartment fuse/relay box. see scheme 4 Check for continuity between MFI relay connector terminal No. 1 and fuel injector intermediate connector B-44 terminal No. 8. see scheme 20and see scheme 26. There should be continuity. Then, check for continuity between ground and MFI relay connector terminal No. 1. There should be no continuity. If continuity is as specified, go to next step. If continuity is not as specified, repair Red wire between MFI relay connector terminal No. 1 and fuel injector intermediate connector B-44 terminal No. 8. Go to step 17.
  15. Check continuity between fuel injector intermediate connector B-44 terminal No. 8 (Red wire) and each fuel injector connector terminal No. 1. There should be continuity. Check continuity between ground and each fuel injector connector terminal No. 1. There should be no continuity. If continuity is as specified, go to next step. If continuity is not as specified, repair or replace circuit wire between fuel injector intermediate connector B-44 terminal No. 8 (Red wire) and each fuel injector connector terminal No. 1. Go to step 17.
  16. Replace fuel injector. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0201-P0206 is output, replace PCM. Go to step 18. If DTC P0201-P0206 is not output, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  17. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Then go to next step.
  18. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0201-P0206 is output, go to step 1, and retry diagnostic procedure. If DTC P0201-P0206 is not output, inspection is complete.

Scheme 38

Scheme 38
Scheme 38

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). Volumetric efficiency is between 30 and 60 percent. Adaptive learning is complete for the vane which generates crankshaft position signal. Engine is running and there is no gear shifting, deceleration, sudden acceleration, or A/C compressor switching occurring. Vehicle speed is 1.6 MPH or more. Throttle deviation is -59-59 millivolts per 10 milliseconds. Misfire is determined by change in angular velocity of Crankshaft Position (CKP) sensor. Code will set if misfire occurred more frequently than allowed during the last 200 revolutions when catalytic converter temperature is more than 1742°F (950°C) or code will set if misfire occurred in 20 or more of last 1000 revolutions (corresponding to 1.5 times the limit of emission standard).

Test Procedures

  1. Start engine and let idle. Using scan tool, check data list item No. 22 (crankshaft position sensor). Check waveform of CKP sensor while keeping engine speed constant. If CKP sensor waveform pulse width is constant, go to next step. If CKP sensor waveform pulse width is not constant, check CKP sensor circuit. See «DTC P0335: CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT MALFUNCTION»(ref-135490-S26282345152002022200000) .
  2. Ensure engine is at normal operating temperature. Turn all accessories off. Increase engine speed to 2500 RPM. Using scan tool, check data list item No. 81 (long-term fuel compensation). At 2500 RPM in closed loop, fuel trim should be -12.5-12.5 percent. If fuel trim is as specified, go to next step. If fuel trim is not as specified, check fuel trim fault. See «DTC P0171: RIGHT BANK SYSTEM TOO LEAN (BANK 1)»(ref-135490-S04200545782002022200000) , «DTC P0172: RIGHT BANK SYSTEM TOO RICH (BANK 1)»(ref-135490-S30334597242003050500000) , «DTC P0174: LEFT BANK SYSTEM TOO LEAN (BANK 2)»(ref-135490-S27208664732002022200000) or «DTC P0175: LEFT BANK SYSTEM TOO RICH (BANK 2)»(ref-135490-S16094158322003050500000) .
  3. Using scan tool, check data list item No. 82 (short-term fuel compensation). At 2500 RPM in closed loop operation, fuel trim should be -10.0-10.0 percent. If fuel trim is as specified, go to next step. If fuel trim is not as specified, check fuel trim fault. See «DTC P0171: RIGHT BANK SYSTEM TOO LEAN (BANK 1)»(ref-135490-S04200545782002022200000) , «DTC P0172: RIGHT BANK SYSTEM TOO RICH (BANK 1)»(ref-135490-S30334597242003050500000) , «DTC P0174: LEFT BANK SYSTEM TOO LEAN (BANK 2)»(ref-135490-S27208664732002022200000) or «DTC P0175: LEFT BANK SYSTEM TOO RICH (BANK 2)»(ref-135490-S16094158322003050500000) .
  4. Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Remove spark plugs and connect to plug wire. Ground spark plug electrode and crank engine. If spark plug fires when engine is cranked, go to step 7 . If spark plug does not fire, go to next step.
  5. Check spark plug gap. Gap should be .039-.043" (1.0-1.1 mm). If problem does not exist, go to next step. If problem exists, replace plugs. Go to step 13 .
  6. Remove plug wires and measure resistance. Maximum resistance for each plug wire is 22 k ohms. If any plug wire resistance is more than specified, replace appropriate plug wire. Go to step 13 . If plug wire resistances are okay, check ignition circuit. See «IGNITION CHECKS»(ref-135483-S36887522802002022200000) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. Then go to next step.
  7. Disconnect fuel injector connectors. Measure resistance between fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If each resistance is as specified, go to next step. If any resistance is not as specified. Go to step 13 .
  8. Check fuel injector connectors and fuel injector intermediate connector B-44 for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair appropriate connector(s). Go to step 13 .
  9. Disconnect PCM connector D-107. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair appropriate connector. Go to step 13 .
  10. Check for continuity in wiring between each fuel injectors connector terminals No. 2 and PCM connector D-107. See «FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS»(ref-135490-S14752298562003050700000) for connector terminal identification. There should be continuity. Then, check for continuity in wiring between ground and each fuel injectors connector terminals No. 2. There should be no continuity. If continuity is as specified, go to next step. If continuity is not as specified, repair appropriate wire between suspect fuel injector(s) connector terminals No. 2 and PCM connector D-107. Go to step 13 .
  11. Check valve timing belt. See TIMING BELT INSPECTION under TIMING BELT in ENGINES - MECHANICAL 3.5L V-6 article. Check engine compression. See «MECHANICAL INSPECTION»(ref-135483-S16804828332002022200000) under PRELIMINARY INSPECTION & ADJUSTMENTS in BASIC DIAGNOSTIC PROCEDURES article. Check EGR system. See «EXHAUST GAS RECIRCULATION (EGR)»(ref-135493-S13375233772002022200000) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If problem does not exist, go to next step. If problem exists, repair as necessary. Go to step 13 .
  12. Replace all injectors. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0300 is output, replace PCM. Go to step 14 . If DTC P0300 is not output, inspection is complete.
  13. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Then go to next step.
  14. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0300 is output, go to step 1 , and retry diagnostic procedure. If DTC P0300 is not output, inspection is complete.

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). Volumetric efficiency is between 30 and 60 percent. Adaptive learning is complete for the vane which generates crankshaft position signal. Engine is running and there is no gear shifting, deceleration, sudden acceleration, or A/C compressor switching occurring. Vehicle speed is 1.6 MPH or more. Throttle deviation is -59-59 millivolts per 10 milliseconds. Misfire is determined by change in angular velocity of Crankshaft Position (CKP) sensor. Code will set if misfire occurred more frequently than allowed during the last 200 revolutions when catalytic converter temperature is more than 1742°F (950°C) or code will set if misfire occurred in 20 or more of last 1000 revolutions (corresponding to 1.5 times the limit of emission standard).

  1. Check spark plug gaps. Gap should be.039-.043" (1.0-1.1 mm). If gaps are as specified, go to next step. If gaps are not as specified, replace plugs. Go to step 9.
  2. Remove plug wires and measure resistance. Maximum resistance for each plug wire is 22 k/ohms. If each plug wire resistance is as specified, go to next step. If any plug wire resistance is not as specified, replace plug wire. Go to step 9.
  3. Disconnect fuel injector 2-pin connectors. Measure resistance between fuel injector connector terminals (component side). Resistance should be 13-16 ohms at 68°F (20°C). If each resistance is as specified, go to next step. If any resistance is not as specified, replace appropriate fuel injector(s). Go to step 9.
  4. Check fuel injector connectors and fuel injector 8-pin intermediate connector B-44 for loose, damaged, or corroded terminals. If problem does not exist, go to next step. If problem exists, repair or replace connector(s). Go to step 9.
  5. Disconnect PCM connector D-107. see scheme 28 Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 9. If problem does not exist, go to next step.
  6. Check for continuity in wiring between each fuel injectors connector terminals No. 2 and PCM connector D-107. See «FUEL INJECTOR TO INTERMEDIATE CONNECTOR TO PCM PIN DESIGNATIONS»(ref-135490-S14752298562003050700000) for connector terminal identification. There should be continuity. Then, check for continuity in wiring between ground and each fuel injectors connector terminals No. 2. There should be no continuity. If continuity is as specified, go to next step. If continuity is not as specified, repair appropriate wire between suspect fuel injector(s) connector terminals No. 2 and PCM connector D-107. Then go to step 9.
  7. Check compression. See «MECHANICAL INSPECTION»(ref-135483-S16804828332002022200000) under PRELIMINARY INSPECTION & ADJUSTMENTS in BASIC DIAGNOSTIC PROCEDURES article. If compression is not within specification, repair engine as necessary. Go to step 9. If compression is within specification, go to next step.
  8. Replace fuel injector. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0301-P0306 is output, replace PCM. Go to step 10. If DTC P0301-P0306 is not output, inspection is complete.
  9. Install intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in appropriate article in ENGINES. Go to next step.
  10. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0301-P0306 is output, retry diagnostic procedure. If DTC P0301-P0306 is not output, inspection is complete.

2 seconds have passed since starting sequence was completed. Engine speed is more than 3000 RPM. Code will set when knock sensor output voltage (peak voltage in each 1/3 turn of crankshaft) has not changed more than 0.06 volt in last consecutive 200 periods.

  1. Disconnect knock sensor 2-pin connector. Check knock sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 6 .
  2. Check for continuity between ground and knock sensor connector terminal No. 2 (Black wire). If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between knock sensor and ground. Go to step 6 .
  3. Disconnect PCM connector D-109. Check PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 6 . If problem does not exist, go to next step.
  4. Check continuity between knock sensor connector terminal No. 1 and PCM connector D-109 terminal No. 90. Continuity should exist. Check continuity between ground and knock sensor connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair White wire. Go to step 6 . If continuity is as specified, go to next step.
  5. Replace knock sensor. Test drive vehicle. Check for DTCs. If DTC P0325 is output, replace PCM. Go to next step. If DTC P0325 is not output, inspection is complete.
  6. Start engine. Using scan tool, check data list item No. 44 (ignition coils and power transistor). While observing scan tool, disconnect knock sensor connector, then reconnect knock sensor connector. When knock sensor is disconnected, timing should be more retarded than when knock sensor is connected. If timing changes as specified, inspection is complete. If timing does not change as specified, go to step 1 and retry diagnostic procedure.

Engine is being cranked. Code will set if CKP sensor output voltage has not changed for 2 seconds. Code will set if normal signal identification pattern has not been input for cylinder identification from CKP sensor and Camshaft Position (CMP) sensor for 2 seconds.

  1. Start engine and let idle. Using scan tool, check data list item No. 22 (crankshaft position sensor). Engine speed displayed on scan tool should match tachometer. If engine speeds match, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If engine speeds do not match, go to next step.
  2. Connect lab scope pick-up at CKP sensor or PCM. If connecting lab scope pick-up at CKP sensor, connect pick-up lead to CKP sensor connector terminal No. 2 (Blue/Red wire) by backprobing. see scheme 15 If connecting lab scope pick-up at PCM, connect pick-up lead to PCM connector D-108 terminal No. 45 (Blue/Red wire) by backprobing. see scheme 28 Start engine and let idle. Compare waveform to normal pattern. (Scheme 39) If waveform is normal, go to next step. If waveform is not normal, go to step 5.
  3. Turn ignition off. Check CKP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 20. If problem does not exist, go to next step.
  4. Start engine and let idle. Using scan tool, check data list item No. 22 (crankshaft position sensor). Engine speed displayed on scan tool should match tachometer. If engine speeds match, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If speeds do not match, replace PCM. Go to step 20.
  5. Turn ignition off. Disconnect CKP sensor 3-pin connector. Check CKP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 20. If problem does not exist, go to next step.
  6. Turn ignition on. Measure voltage between ground and CKP sensor connector terminal No. 2 (Blue/Red wire). see scheme 15 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 11. If voltage is not as specified, go to next step.
  7. Measure voltage between ground and PCM connector D-108 terminal No. 45 (Blue/Red wire) by backprobing. see scheme 28 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 9.
  8. Turn ignition off. Disconnect PCM connector D-108. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 20. If problem does not exist, repair Blue/Red wire between CKP sensor connector terminal No. 2 and PCM connector D-108 terminal No. 45. Go to step 20.
  9. Turn ignition off. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 20. If problem does not exist, go to next step.
  10. Check continuity between ground and CKP sensor connector terminal No. 2. see scheme 15 Continuity should not exist. If continuity exists, repair short to ground in Blue/Red wire. Go to step 20. If problem does not exist, replace PCM. Go to step 20.
  11. Measure voltage between ground and CKP sensor connector terminal No. 3 (Red wire). Battery voltage should exist. If voltage is as specified, go to step 13. If voltage is not as specified, go to next step.
  12. Turn ignition off. Remove and check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 20. If problem does not exist, repair Red wire between MFI relay and CKP sensor. Go to step 20.
  13. Turn ignition off. Check for continuity between ground and CKP sensor connector terminal No. 1 (Black wire). If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between CKP sensor and ground. Go to step 20.
  14. Remove MFI relay. Check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 20. If problem does not exist, go to next step.
  15. Disconnect PCM connector D-108. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 20. If problem does not exist, go to next step.
  16. Check continuity between MFI relay connector terminal No. 1 and CKP sensor connector terminal No. 3. Continuity should exist. Then, check continuity between ground and MFI relay connector terminal No. 1. Continuity should not exist. see scheme 15and see scheme 26. If continuity is not as specified, repair Red wire. Go to step 20. If continuity is as specified, go to next step.
  17. Check continuity between CKP sensor connector terminal No. 2 and PCM connector D-108 terminal No. 45 (Blue/Red wire). Continuity should exist. Check continuity between ground and CKP sensor connector terminal No. 2 (Blue/Red wire). Continuity should not exist. If continuity is not as specified, repair Blue/Red wire. Go to step 20. If continuity is as specified, go to next step.
  18. Check for continuity between ground and CKP sensor connector terminal No. 1 (Black wire). If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between CKP sensor and ground. Go to step 20.
  19. Visually check CKP sensor vane. If problem exists, repair or replace cKP sensor vane. Go to next step. If problem does not exist, replace CKP sensor. Go to next step.
  20. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0335 is output, go to step 1 and retry diagnostic procedure. If DTC P0335 is not output, inspection is complete.

Scheme 39

Scheme 39
Scheme 39
  1. Engine speed is more than 50 RPM. Code will set if CMP sensor output voltage has not changed for 2 seconds.
  2. Engine speed is more than 50 RPM. Code will set if normal cylinder identification signal pattern from CMP sensor and Crankshaft Position (CKP) sensor has not been input for 2 seconds.
  1. Connect lab scope pick-up at CMP sensor connector or PCM. If connecting lab scope pick-up at CMP sensor connector, connect lab scope pick-up lead to CMP sensor connector terminal No. 2 (Blue wire) by backprobing. see scheme 12 If connecting lab scope at PCM, connect pick-up lead to PCM connector D-108 terminal No. 56 (Blue wire) by backprobing. see scheme 28 Start engine and let idle. Compare waveform to a normal pattern. (Scheme 39) If waveform is normal, go to next step. If waveform is not normal, go to step 4.
  2. Turn ignition off. Disconnect and check CMP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 19. If problem does not exist, reconnect CMP sensor and go to next step.
  3. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0340 is output, replace PCM. Go to step 19. If DTC P0340 is not output, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  4. Turn ignition off. Disconnect 3-pin intermediate connector B-08 in CMP sensor circuit. Check intermediate connector B-08 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 19. If problem does not exist, go to next step.
  5. Turn ignition on. Measure voltage between ground and 3-pin intermediate connector B-08 terminal No. 2 (Blue wire). see scheme 12 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 10. If voltage is not as specified, go to next step.
  6. Measure voltage between ground and PCM connector D-108 terminal No. 56 (Blue wire) by backprobing. see scheme 28 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 8.
  7. Turn ignition off. Disconnect and check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 19. If problem does not exist, repair wire between 3-pin intermediate connector B-08 terminal No. 2 (Blue wire) and PCM connector D-108. Go to step 19.
  8. Turn ignition off. Disconnect and check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 19. If problem does not exist, go to next step.
  9. Check continuity between 3-pin intermediate connector B-08 terminal No. 2 (Blue wire) in CMP sensor circuit and PCM connector D-108 terminal No. 56. Continuity should exist. Then, check continuity between ground and 3-pin intermediate connector B-08 terminal No. 2. Continuity should not exist. If continuity is not as specified, check intermediate connector B-08 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. If problem does not exist, repair Blue wire. Go to step 19. If problem does not exist, replace PCM. Go to step 19.
  10. Measure voltage between ground and 3-pin intermediate connector B-08 terminal No.3 (Red wire). If battery voltage exists, go to step 12. If battery voltage does not exist, go to next step.
  11. Turn ignition off. Remove and check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 19. If problem does not exist, repair open or short to ground between MFI relay and 3-pin intermediate connector B-08 terminal No. 3 (Red wire). Go to step 19.
  12. Turn ignition off. Check for continuity between ground and 3-pin intermediate connector B-08 terminal No. 1 (Black wire). If continuity exists, go to next step. If continuity does not exist, repair Black wire between 3-pin intermediate connector B-08 terminal No. 1 and ground. Go to step 19.
  13. Remove and check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 19. If problem does not exist, go to next step.
  14. Disconnect and check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 19. If problem does not exist, go to next step.
  15. Check intermediate connector B-08 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. If problem does not exist, reconnect 3-pin intermediate connector B-08. Disconnect CMP sensor connector. Check continuity between MFI relay connector terminal No. 1 and CMP sensor connector terminal No. 3 (Red wire). see scheme 12and see scheme 26. Continuity should exist. Then, check continuity between ground and CMP sensor connector terminal No. 3 (Red wire). Continuity should not exist. If continuity is not as specified, repair Red wire. Go to step 19. If continuity is as specified, go to next step.
  16. Check continuity between CMP sensor connector terminal No. 2 and PCM connector D-108 terminal No. 56 (Blue wire). see scheme 12and see scheme 28. Continuity should exist. Then, check continuity between ground and CMP sensor connector terminal No. 2 (Blue wire). Continuity should not exist. If continuity is not as specified, repair Blue wire. Go to step 19. If continuity is as specified, go to next step.
  17. Check continuity between CMP sensor connector terminal No. 1 (Black wire) and ground. Continuity should exist. Reconnect MFI relay and PCM connector D-108. Turn ignition on. Measure voltage between ground and CMP sensor connector terminal No. 1. Voltage should be less than 0.5 volt. If problem exists, repair open or short in Black wire. Go to step 19. If problem does not exist, go to next step.
  18. Visually inspect CMP sensor vane. If problem exists, repair vane. Go to next step. If problem does not exist, replace CMP sensor. Go to next step.
  19. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0340 is output, go to step 1 and retry diagnostic procedure. If DTC P0340 is not output, inspection is complete.

There are 3 monitors, 2 seconds each, during each drive cycle. At least 20 seconds have passed since last monitor was complete. Engine coolant temperature is more than 169°F (76°C). Engine speed is 910-1650 RPM. 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. At least 90 seconds have passed since manifold differential pressure sensor output voltage changed 1.5 volts or more. Throttle valve is closed. Volumetric efficiency is less than 28 percent. Code will be set if pressure fluctuations width is lower than 0.37 psi (2.6 kPa). When EGR solenoid is turned on.

  1. Check EGR system. See «EXHAUST GAS RECIRCULATION (EGR)»(ref-135493-S13375233772002022200000) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If problem exists, repair as necessary and go to step 3 . If problem does not exist, go to next step.
  2. Start engine and warm up to normal operating temperature. Using scan tool, check data list item No. 95 (manifold differential pressure sensor). With engine idling, manifold differential pressure should read 62-76 kPa. If manifold differential pressure is as specified, clean EGR valve and EGR passage. Go to next step. If manifold differential pressure is not as specified, check manifold differential pressure sensor circuit malfunction. See «DTC P1400: MANIFOLD DIFFERENTIAL PRESSURE (MDP) SENSOR CIRCUIT MALFUNCTION»(ref-135490-S35530958702002022200000) .
  3. Test drive vehicle following OBD-II drive cycle EGR monitor pattern. See «EGR MONITOR»(ref-135490-S42459438792002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0401 is output, retry diagnostic procedure. If DTC P0401 is not output, inspection is complete.
  1. Monitor runs once during drive cycle. Engine is being cranked. Battery voltage is between 10 and 16 volts. Code will be set if EGR solenoid coil surge voltage (system voltage plus 2 volts) is not detected for 0.2 second.
  2. Battery voltage is between 10 and 16 volts. ON duty cycle of the EGR solenoid is between 10 and 90 percent. ON duty cycle of the EVAP emission purge valve solenoid is 0 percent. EVAP emission ventilation solenoid is OFF. More than 1 second has elapsed after the above mentioned conditions have been met. Code will be set if EGR solenoid coil surge voltage (system voltage plus 2 volts) is not detected for 1 second.
  1. Turn ignition on. Using scan tool, select actuator test item No. 10 (EGR solenoid). EGR solenoid should make clicking sound and vibrate when actuated. If EGR solenoid performs as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If EGR solenoid does not perform as specified, exit actuator test and go to next step.
  2. Turn ignition off. Disconnect EGR solenoid 2-pin connector. Check EGR solenoid connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  3. Measure resistance between EGR 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 EGR solenoid. Go to step 12.
  4. Turn ignition on. Measure voltage between ground and EGR solenoid connector terminal No. 1 (Red wire). If battery voltage exists, go to step 6. If battery voltage does not exist, go to next step.
  5. Turn ignition off. Remove and check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 12. If problem does not exist, repair open in Red wire between MFI relay and EGR solenoid. Go to step 12.
  6. Measure voltage between ground and PCM connector D-107 terminal No. 6 (Green/White wire) by backprobing. see scheme 28 If battery voltage exists, go to step 9. If battery voltage does not exist, go to next step.
  7. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  8. Check continuity between PCM connector D-107 terminal No. 6 and EGR solenoid connector terminal No. 2 (Green/White wire). see scheme 16and see scheme 26. Continuity should exist. Then, check continuity between ground and EGR solenoid connector terminal No. 2 (Green/White wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Green/White wire. Go to next step. If continuity is as specified, replace PCM. Go to next step.
  9. Turn ignition off. Disconnect and check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  10. Remove MFI relay. Check continuity between MFI relay connector terminal No. 1 and EGR solenoid connector terminal No. 1 (Red wire). see scheme 16and see scheme 26. Continuity should exist. Then, check continuity between ground and EGR solenoid connector terminal No. 1 (Red wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Red wire. Go to step 12. If continuity is as specified, go to next step.
  11. Check continuity between PCM connector D-107 terminal No. 6 and EGR solenoid connector terminal No. 2 (Green/White wire). see scheme 16and see scheme 26. Continuity should exist. Then, check continuity between ground and EGR solenoid connector terminal No. 2 (Green/White wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in Green/White wire. Go to next step. If continuity is as specified, replace PCM. Go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0403 is output, go to step 1 and retry diagnostic procedure. If DTC P0403 is not output, inspection is complete.

DTC will set under following conditions: Engine speed is less than 3000 RPM. Volume Air Flow (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). Throttle valve is open. Engine is in closed loop air/fuel control. Vehicle speed is one MPH or more. Code will set if rear Heated Oxygen Sensor (HO2S) signal becomes similar to front HO2S signal. Monitor runs 84 seconds.

Note. Engine and catalytic converter need to be cold at beginning of this procedure. First 2 steps must be performed before catalytic converter lights off.

  1. Check right bank (DTC P0421) or left bank (DTC P0431) exhaust manifold and front exhaust pipe for cracks. If problem exists, replace manifold or front exhaust pipe as necessary. Go to step 7 . If problem does not exist, go to next step.
  2. Start engine. Using scan tool, check data list item No. 69 (right rear heated oxygen sensor) or data list item No. 59 (left rear heated oxygen sensor). When engine is revved, rear HO2S output voltage should alternate between about zero volts and 0.6-1.0 volt. If scan tool readings are as specified, go to next step. If voltage is not as specified, check appropriate rear Heated Oxygen Sensor (HO2S) circuit. See «DTC P0137: RIGHT REAR HO2S CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)»(ref-135490-S16795968702002022200000) , «DTC P0139: RIGHT REAR HO2S CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2)»(ref-135490-S42363347362003050500000) , «DTC P0157: LEFT REAR HO2S CIRCUIT LOW VOLTAGE (BANK 2 SENSOR 2)»(ref-135490-S23732266602002022200000) or «DTC P0159: LEFT REAR HO2S CIRCUIT SLOW RESPONSE (BANK 2 SENSOR 2)»(ref-135490-S32078717752003050500000) .
  3. Using scan tool, check data list item No. 39 (right front heated oxygen sensor) or data list item No. 11 (left front heated oxygen sensor). When engine is revved, front HO2S output voltage should be 0.6-1.0 volt. If voltage is as specified, go to next step. If voltage is not as specified, check front HO2S circuit. See «DTC P0132: RIGHT FRONT HO2S CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 1)»(ref-135490-S02794853672002022200000) , «DTC P0133: RIGHT FRONT HO2S CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 1)»(ref-135490-S15132600082003050200000) , «DTC P0134: RIGHT FRONT HO2S CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 1)»(ref-135490-S24067465092003050200000) , «DTC P0152: LEFT FRONT HO2S CIRCUIT HIGH VOLTAGE (BANK 2 SENSOR 1)»(ref-135490-S41901481812002022200000) , «DTC P0153: LEFT FRONT HO2S CIRCUIT SLOW RESPONSE (BANK 2 SENSOR 1)»(ref-135490-S01457528132003050500000) or «DTC P0154: LEFT FRONT HO2S CIRCUIT NO ACTIVITY DETECTED (BANK 2 SENSOR 1)»(ref-135490-S35181901492003050500000) .
  4. Hold engine speed at 2000 RPM and monitor front HO2S output voltage. Scan tool reading should alternate between 0.4 volt or less and 0.6 volt or more at least 15 times or more within 10 seconds. If voltage switches as specified, go to next step. If voltage does not switch as specified, replace appropriate front HO2S. Go to step 7 .
  5. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135490-S41145705502002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0421 is output, replace right bank catalytic converter. Go to next step. If DTC P0431 is output, replace left bank catalytic converter. Go to next step. If DTC P0421 or P0431 is not output, inspection is complete.
  6. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135490-S41145705502002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0421 or P0431 is output, replace PCM. Go to next step. If DTC P0421 or P0431 is not output, inspection is complete.
  7. Test drive vehicle following OBD-II drive cycle catalytic converter monitor pattern. See «CATALYTIC CONVERTER MONITOR»(ref-135490-S41145705502002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0421 or P0431 is output, go to step 1 and retry diagnostic procedure. If DTC P0421 or P0431 is not output, inspection is complete.

ON duty cycle of EVAP emission purge solenoid is 0 percent. 20 seconds have elapsed from the time the duty cycle for EVAP emission purge solenoid has turned to 0 percent. Code will set when pressure in fuel tank is 0.29 psi (-2 kPa) or less.

  1. Turn ignition on. Using scan tool, select actuator test item No. 8 (purge solenoid) and turn on (open) purge solenoid. When actuated, purge solenoid should make operating sound and vibrate. If purge solenoid does not operate as specified, replace EVAP emission purge solenoid and go to step 4 . If purge solenoid operates as specified, go to next step.
  2. Turn ignition on. Using scan tool, select actuator test item No. 29 (ventilation solenoid) and turn on (open) ventilation solenoid. When actuated, purge solenoid should make operating sound and vibrate. If ventilation solenoid does not operate as specified, replace EVAP emission ventilation solenoid and go to step 4 . If ventilation solenoid operates as specified, go to next step.
  3. Check EVAP system purge control solenoid vent hoses. Check for a clogged air filter. Repair or replace if necessary. Then go to next step. If hoses and air filter are OK, refer to «DTC P0451, DTC P0452 &/OR DTC P0453»(ref-135490-S29330585062002022200000) and troubleshoot.
  4. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAP SYSTEM LEAK MONITOR»(ref-135490-S23094847262002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0441 is output, retry diagnostic procedure. If DTC P0441 is not output, inspection is complete.

When remaining fuel in tank is 15-40 percent (fuel level sensor voltage is 1.4-2.4 volts), PCM checks under the following monitor conditions

Test Conditions A: At Start Up

  1. Intake air temperature is 97°F (36°C) or less when engine started.
  2. Engine coolant temperature was 97°F (36°C) or less when engine started.

Test Conditions B: For Test To Run

  1. Fuel temperature is 97°F (36°C) or less.
  2. Not more than 16 minutes have passed since engine started.
  3. Engine coolant temperature is more than 140°F (60°C).
  4. Power steering pressure switch is off.
  5. Barometric pressure is more than 11 psi (76 kPa).
  6. Volumetric efficiency is 20-70 percent.
  7. Fuel tank differential pressure sensor output voltage is 1-4 volts.
  8. Vehicle speed is 12.4 MPH or more.

Test Conditions C: For Test To Stop

  1. Intake air temperature was 41°F (5°C) or less.
  2. EVAP system emission purge solenoid and EVAP emission ventilation solenoid are closed, the pressure rises higher than 0.065 psi (0.451 kPa).
  3. The pressure fluctuation width is greater than 0.094 psi (0.647 kPa).

Code will set if internal pressure of fuel tank changes more than 0.122 psi (0.843 kPa) in 20 seconds after tank and vapor lines are closed. Monitoring time is dependent upon fuel level and temperature in the fuel tank and is between 75-125 seconds.

When remaining fuel in tank is 40-75 percent (fuel level sensor voltage is (2.4-3.7 volts), PCM checks under the following monitor conditions

Test Conditions A: At Start Up

  1. Intake air temperature is 97°F (36°C) or less when engine started.
  2. Engine coolant temperature is 97°F (36°C) or less when engine started.

Test Conditions B: For Test To Run

  1. Fuel temperature is 97°F (36°C) or less.
  2. Barometric pressure is more than 11 psi (76 kPa).
  3. Volumetric efficiency is 20-70 percent.
  4. Fuel tank differential pressure sensor output voltage is 1-4 volts.

Test Conditions C: For Test To Stop

  1. Intake air temperature was 14°F (-10°C) or less.
  2. Engine coolant temperature is 687°F (20°C).
  3. EVAP system emission purge solenoid and EVAP emission ventilation solenoid are closed, the pressure rises higher than 0.047 psi (0.324 kPa).

Code will set if internal pressure of fuel tank changes more than 0.29 psi (2 kPa) in 128 seconds after tank and vapor lines are closed. Monitoring time is dependent upon fuel level and temperature in the fuel tank and is between 75-125 seconds.

Note. The following test procedure requires functions available on manufacturer's MUT-II scan tool. Generic scan tools may not have the capability to carry out test.

Note. An improperly tightened fuel cap can cause this code to set. Check for properly installed fuel cap and a good seal between the fuel cap and fuel filler neck.

  1. Ensure transaxle is in Park and fuel cap is securely tightened (3 clicks). Start engine and let idle. Clear DTCs. Using MUT-II scan tool, start EVAP system leak monitor test. Select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. When monitor starts, IN PROGRESS item on scan tool will change from NO to YES. If EVAP LEAK MON. COMPLETED. TEST PASSED is displayed, EVAP system currently is working properly. Code was probably set by improperly installed fuel cap. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, go to next step. If EVAP LEAK MON. DISCONTINUED is displayed, turn ignition off and start monitor over. NOTE: Monitor test will automatically increase engine speed. If engine speed does not reach 1600 RPM or more during monitor test, adjustment of fixed Speed Adjusting Screw (SAS) may be needed. See «FIXED SPEED ADJUSTING SCREW»(ref-135481-S36550359252002022200000) under IDLE SPEED & MIXTURE in ON-VEHICLE ADJUSTMENTS article. NOTE: When fuel nozzle is inserted into filler neck and fuel overflow limiter valve flapper door is opened, fuel overflow limiter valve plunger moves toward top of neck and closes fuel overflow limiter valve. When fuel cap is installed, cap pushes fuel overflow limiter valve plunger back in, which opens fuel overflow limiter valve. If flapper door or fuel overflow limiter valve plunger do not operate properly, fuel overflow limiter valve plunger may interfere with fuel cap seating properly. This can cause DTC P0442 to set.
  2. Disconnect hoses "A" and "B" at purge solenoid side. (Scheme 40), (Scheme 41) & (Scheme 43). Connect hand pressure/vacuum pump to purge solenoid port from which hose "B" was disconnected. Turn ignition on. Using scan tool, select actuator test item No. 8 (purge solenoid). When purge solenoid is actuated, using hand pressure/vacuum pump, apply pressure. Verify pressure blows through the other port. If pressure blows through, go to next step. If pressure does not blow through, replace purge solenoid valve. Then go to step 17.
  3. Thoroughly check hoses "A", "B" & "C" for damage or leaks. If the hoses are OK, go to next step. If hoses are damaged, replace as necessary. Go to step 17.
  4. Disconnect hose "T" at ventilation solenoid side. (Scheme 40), (Scheme 41) and (Scheme 43). Connect hand pressure/vacuum pump to ventilation solenoid port from which hose "T" was disconnected. Turn ignition on. Using scan tool, select actuator test item No. 29 (ventilation solenoid). When ventilation solenoid is actuated, using hand pressure/vacuum pump, apply pressure. Verify pressure is held. If pressure is held, go to next step. If pressure is not held, replace ventilation solenoid valve. Then go to step 17.
  5. Thoroughly check hose "T" for damage or leaks. If the hose is OK, go to next step. If hose is damaged, replace as necessary. Go to step 17.
  6. Thoroughly check hose "F" for damage or leaks. If the hose is OK, go to next step. If hose is damaged, replace as necessary. Go to step 17.
  7. Confirm Miller EVAP System Pressure Pump (6872A) is operating properly. Perform self-test as described by manufacturer. Pressure test for leaks in the EVAP system between hose "G" to hose "S". Remove fuel cap. Disconnect hose "G" from EVAP canister side and plug. Connect EVAP system pressure pump to fuel filler neck. Perform pressure test (I/M240 simulation test) described in EVAP system pressure pump manufacturer's instructions located in lid of pump box. If leak is indicated, connect hose "G" to EVAP canister and go to next step. If leak is not indicated, go to step 15.
  8. Remove the fuel tank filler neck protector. Disconnect hose "H" from EVAP canister side and connect a hand pressure/vacuum pump. (Scheme 40)and (Scheme 41). Pressurize hose "G" and verify pressure is maintained. If leak is not indicated, go to next step. If leak is indicated, replace defective hose, reinstall filler neck protector and go to step 17.
  9. Thoroughly check hoses "H", "I", "J", "K", "L" M", "N" and "O" for damage clogging or leaks. If the hoses are not damaged or clogged, go to next step. If hoses are damaged so clogged, replace as necessary. Go to step 17.
  10. Inspect check valve "A". (Scheme 40), (Scheme 41) and (Scheme 43). Only when air is blown through the valve in the direction shown in the figure, should it pass air. If the valve is good, go to next step. If the valve is bad, replace valve, reinstall filler neck protector and go to step 17.
  11. Inspect check valve "B". (Scheme 40), (Scheme 41) and (Scheme 43). When air is blown through the valve in the direction shown in the top of figure, should it pass more air as compared to when air blown through valve in the direction shown in the bottom of figure. If the valve is good, go to next step. If the valve is bad, replace valve, reinstall filler neck protector and go to step 17.
  12. Remove fuel tank. Using hand vacuum pump, check hoses "P" and "S" for leaks. (Scheme 40)and (Scheme 41). If leak is indicated, replace appropriate hose, install fuel tank. Go to step 17. If leak does not exist, go to next step.
  13. Visually check fuel tank for cracks and leaks. Connect EVAP system pressure pump to fuel return hose. See. Plug all openings on fuel tank. Using EVAP system pressure pump, pressurize fuel tank. Check for leaks by applying soap to each section of fuel tank. If leak exists, repair leak, install fuel tank and fuel filler neck protector. Go to step 17. If leak does not exist, install fuel tank and fuel filler neck protector. Go to next step.
  14. Ensure transaxle is in Park and fuel cap is securely tightened (3 clicks). Start engine and let idle. Using MUT-II scan tool, start EVAP system leak monitor test. Select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. When monitor starts, IN PROGRESS item on scan tool will change from NO to YES. If EVAP LEAK MON. COMPLETED. TEST PASSED is displayed, EVAP system currently is working properly. Go to step 17. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, replace PCM and go to step 17. If EVAP LEAK MON. DISCONTINUED is displayed, turn ignition off and start monitor over.
  15. Remove fuel tank assembly. Using hand vacuum pump, check hoses "D" to "E" for leaks. (Scheme 40)and (Scheme 41). If leak is indicated, replace appropriate hose, install fuel tank assembly. Go to step 17. If leak is not indicated, go to next step.
  16. Remove EVAP canister. Connect hand vacuum pump to canister directly. Plug the other 2 nipples. Apply pressure on the hand pressure/vacuum pump, and confirm the pressure is held. If the pressure is held, go to step. If pressure is not held, replace EVAP canister and go to next step.
  17. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAP SYSTEM LEAK MONITOR»(ref-135490-S23094847262002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTCs P0442 or P0456 is output, go to step 1 and retry diagnostic procedure. If DTCs P0442 or P0456 is not output, inspection is complete.

Scheme 40

Scheme 40
Scheme 40

Scheme 41

Scheme 41
Scheme 41

Scheme 42

Scheme 42
Scheme 42

Scheme 43

Scheme 43
Scheme 43

Scheme 44

Scheme 44
Scheme 44
  1. Battery voltage is more than 10 volts. Code will set if purge solenoid coil surge voltage (system voltage plus 2 volts) is not detected within 30 milliseconds. Only one monitor runs during drive cycle.
  2. Battery voltage is more than 10 volts. ON duty cycle of EVAP purge solenoid is between 10 and 90 percent. ON duty cycle of EGR solenoid is 0 percent. EVAP ventilation solenoid is OFF. More than 1 second has elapsed since the above mentioned conditions have been met. Code will set if purge solenoid coil surge voltage (system voltage plus 2 volts) is not detected 1 second.
  1. Turn ignition on. Using scan tool, select actuator test item No. 8 (purge solenoid) and turn on (open) purge solenoid. When actuated, purge solenoid should make operating sound and vibrate. If purge solenoid does not operate as specified, go to next step. If purge solenoid operates as specified, fault is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  2. Exit actuator test. Turn ignition off. Disconnect purge solenoid 2-pin connector. Check purge solenoid connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  3. Measure resistance between 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 purge solenoid. Go to step 12.
  4. Turn ignition on. Measure voltage between ground and purge solenoid connector terminal No. 2 (Red wire). If battery voltage exists, go to step 6. If battery voltage does not exist, go to next step.
  5. Turn ignition off. Check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 12. If problem does not exist, repair Red wire between MFI relay and purge solenoid. Go to step 12.
  6. Turn ignition on. Measure voltage between ground and PCM connector D-107 terminal No. 34 (Brown/White wire) by backprobing. see scheme 29 If battery voltage exists, go to step 9. If battery voltage does not exist, go to next step.
  7. Turn ignition off. Disconnect and check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  8. Check continuity between purge solenoid connector terminal No. 1 and PCM connector D-107 terminal No. 34. Continuity should exist. Then, check continuity between ground and purge solenoid connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair Brown/White wire. Go to step 12. If continuity is as specified, replace PCM. Go to step 12.
  9. Turn ignition off. Disconnect and check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  10. Remove MFI relay. Check continuity between MFI relay connector terminal No. 1 and purge solenoid connector terminal No. 2. see scheme 26and see scheme 29. Continuity should exist. Then, check continuity between ground and purge solenoid connector terminal No. 2. Continuity should not exist. If continuity is not as specified, repair Red wire. Go to step 12. If continuity is as specified, go to step.
  11. Check continuity between purge solenoid connector terminal No. 1 and PCM connector D-107 terminal No. 34. Continuity should exist. Then, check continuity between ground and purge solenoid connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair Brown/White wire. Go to next step. If continuity is as specified, replace PCM. Go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0443 is output, go to step 1 and retry diagnostic procedure. If DTC P0443 is not output, inspection is complete.
  1. Battery voltage is more than 10 volts. Code will set if ventilation solenoid coil surge voltage (system voltage plus 2 volts) is not detected within 30 milliseconds. Only one monitor runs during drive cycle.
  2. Battery voltage is more than 10 volts. ON duty cycle of EVAP purge solenoid and EGR solenoid is 0 percent. EVAP ventilation solenoid is ON. More than 1 second has elapsed since the above mentioned conditions have been met. Code will set if purge solenoid coil surge voltage (system voltage plus 2 volts) is not detected 1 second.
  1. Turn ignition on. Using scan tool, select actuator test item No. 29 (ventilation solenoid) and turn on (close) ventilation solenoid. Ventilation solenoid should vibrate and make operating sound when actuated. If ventilation solenoid does not operate as specified, go to next step. If ventilation solenoid operates as specified, fault is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  2. Exit actuator test. Turn ignition off. Disconnect ventilation solenoid 2-pin connector. Check ventilation solenoid connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  3. Measure resistance between ventilation 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 vent valve module. Go to step 12.
  4. Turn ignition on. Measure voltage between ground and ventilation solenoid connector terminal No. 2 (Red wire). If battery voltage exists, go to step 6. If battery voltage does not exist, go to next step.
  5. Turn ignition off. Remove MFI relay and check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 12. If problem does not exist, repair Red wire between MFI relay and ventilation solenoid. Go to step 12.
  6. Turn ignition off. Measure voltage between ground and PCM connector D-107 terminal No. 35 (Green/Red wire) by backprobing. see scheme 33 If battery voltage exists, go to step 9. If battery voltage does not exist, go to next step.
  7. Turn ignition off. Disconnect and check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  8. Check continuity between ventilation solenoid connector terminal No. 1 and PCM connector D-107 terminal No. 35. Continuity should exist. Then, check continuity between ground and ventilation solenoid connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair Green/Red wire. Go to step 12. If continuity is as specified, replace PCM. Go to step 12.
  9. Turn ignition off. Disconnect and check PCM 35-pin connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  10. Remove MFI relay. Check continuity between MFI relay connector terminal No. 1 and ventilation solenoid connector terminal No. 2. see scheme 26and see scheme 33. Continuity should exist. Then, check continuity between ground and ventilation solenoid connector terminal No. 2. Continuity should not exist. If continuity is not as specified, repair Red wire. Go to step 12. If continuity is as specified, go to step.
  11. Check continuity between ventilation solenoid connector terminal No. 1 and PCM connector D-107 terminal No. 35. Continuity should exist. Then, check continuity between ground and ventilation solenoid connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair Green/Red wire. Go to next step. If continuity is as specified, replace PCM. Go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0446 is output, retry diagnostic procedure. If DTC P0446 is not output, inspection is complete.

Note. In rare cases, this DTC may set under some fuel and driving conditions regardless of fuel pressure sensor output voltage when fuel system is clogged.

  1. Intake air temperature is more than 41°F (5°C). Engine speed is 1600 RPM or more. Volumetric efficiency is 25-80 percent. Vehicle speed is 19 MPH or more. Purge solenoid is driven at 100 percent duty cycle when intake air temperature is 41-113°F (5-45°C). Code will set if Fuel Tank Differential Pressure (FTDP) sensor output voltage stays at 4 volts or more for 10 seconds.
  2. Intake air temperature is more than 41°F (5°C). Engine speed is 1600 RPM or more. Volumetric efficiency is 20-80 percent. Vehicle speed is 19 MPH or more. Purge solenoid is not driven when intake air temperature is 41°F (5°C) or more. Code will set if FTDP sensor output voltage stays at less than one volt for 10 seconds.
  3. Idle switch is on. Vehicle speed is less than one MPH. Engine speed is less than 2500 RPM. Powertrain Control Module (PCM) is looking for electrical noise on FTDP sensor circuit. Code will set if rapid voltage changes of 0.2 volt or more occur at least 20 times in 25 millisecond blocks for 8 consecutive idling periods.
  1. Disconnect hose "G" from EVAP canister and plug. (Scheme 40)and (Scheme 41). Remove fuel cap. Turn ignition on. Using scan tool, check data list item No. 73 (fuel tank pressure differential sensor). Scan tool pressure reading should be -0.97- 0.97 In. Hg (-3.3-3.3 kPa). Connect Miller EVAP System Pressure Pump (6872A) to fuel filler neck and apply pressure. Scan tool reading should increase. If readings are not as specified, go to next step. If readings are as specified, reconnect hose "G". Then go to step 18.
  2. Turn ignition off. Tilt up second seat and access service hole in floor. Remove service hole upper and lower covers and packing. Disconnect FTDP sensor 3-pin connector. Using jumper wires, connect terminals No. 1, 2 and 3 on harness side of FTDP sensor connector to respective terminals on sensor side of FTDP sensor connector. Turn ignition on. Ensure fuel cap is removed. Check voltage between ground and FTDP sensor connector terminal No. 1 (component side). Voltage should be 2-3 volts. With Miller EVAP System Pressure Pump (6872A) to fuel filler neck and apply pressure. Voltage reading should increase. Turn ignition off. If voltage is not as specified, go to next step. If voltage is as specified, go to step 7.
  3. Turn ignition on. Measure voltage between ground and FTDP sensor connector terminal No. 3 (Green/Red wire). see scheme 21 Voltage should be 4.7-5.1 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 11.
  4. Turn ignition on. Measure voltage between ground and FTDP sensor connector terminal No. 2 (Black wire). see scheme 21 Voltage should be less than 0.5 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 15.
  5. Turn ignition off. Disconnect PCM connector D-108, D-109, FTDP sensor connector, intermediate connectors D-112, E-111 and F-07. Check connectors for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s), reconnect hose "G" then go to step 18. If problem does not exist, go to next step.
  6. Disconnect PCM connector D-108 and FTDP sensor connector. Check continuity between PCM connector D-108 terminal 57 and FTDP sensor connector terminal No. 2. Continuity should exist. Then, check continuity between ground and FTDP sensor connector terminal No. 2 (Black wire). Continuity should not exist. Reconnect PCM connector D-108. Check continuity between ground and FTDP sensor connector terminal No. 2 (Black wire). Continuity should exist. If continuity is not as specified, repair the open circuit in Black wire, reconnect hose "G". Go to step 18. If continuity is as specified, replace FTDP sensor, reconnect hose "G". Go to step 18.
  7. Turn ignition on. Ensure fuel cap is removed. Check voltage between ground and PCM connector D-109 terminal No. 92 by backprobing. see scheme 28 Voltage should be 2-3 volts. With Miller EVAP System Pressure Pump (6872A) to fuel filler neck and apply pressure. Voltage reading should increase. Turn ignition off. If voltage is not as specified, go to step 9. If voltage is as specified, go to next step.
  8. Disconnect and check PCM connector D-109 and FTDP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector, reconnect hose "G". Go to step 18. If problem does not exist, go to step 10.
  9. Turn ignition off. Disconnect PCM connector D-109, FTDP sensor connector, intermediate connectors D-112, E-111 and F-07. Check connectors for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s), reconnect hose "G" then go to step 18. If problem does not exist, repair open circuit in Blue/Yellow wire between PCM connector D-109 terminal No. 92 (Brown/Yellow wire) and FTDP sensor connector terminal No. 1 (Blue/Yellow wire), reconnect hose "G". Then go to step 18.
  10. Remove fuel cap. Turn ignition on. Using scan tool, check data list item No. 73 (fuel tank pressure differential sensor). Scan tool pressure reading should be -0.97- 0.97 In. Hg (-3.3-3.3 kPa). Connect Miller EVAP System Pressure Pump (6872A) to fuel filler neck and apply pressure. Scan tool reading should increase. If readings are not as specified, replace PCM, reconnect hose "G". Then go to step 18. If readings are as specified, fault is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). Reconnect hose "G". Go to step 18.
  11. Measure voltage between ground and PCM connector D-108 terminal No. 46 (Green/Yellow wire) by backprobing. see scheme 28 Voltage should be 4.7 and 5.1 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step 13.
  12. Turn ignition off. Check PCM connector D-108, FTDP sensor connector, intermediate connectors D-112, E-111 and F-07 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 18. If problem does not exist, repair Green/Yellow wire between PCM connector D-108 terminal No. 46 and FTDP sensor connector terminal No. 3, reconnect hose "G". Go to step 18.
  13. Turn ignition off. Check PCM connector D-108, FTDP sensor connector, intermediate connectors D-112, E-111 and F-07 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 18. If problem does not exist, go to next step.
  14. Check continuity between PCM connector D-108 terminal 46 (Green/Yellow wire) and FTDP sensor connector terminal No. 3 (Green/Red wire). Continuity should exist. Then, check continuity between ground and FTDP sensor connector terminal No. 3 (Green/Red wire). Continuity should not exist. If continuity is not as specified, repair the open circuit in wire between PCM connector D-108 terminal 46 (Green/Yellow wire) and FTDP sensor connector terminal No. 3 (Green/Red wire), reconnect hose "G". Go to step 18. If continuity is as specified, replace FTDP sensor, reconnect hose "G". Go to step 18.
  15. Turn ignition on. Measure voltage between ground and PCM connector D-108 terminal No. 57 (Black wire). see scheme 28 Voltage should be less than 0.5 volt. If voltage is as specified, go to next step. If voltage is not as specified, go to step 17.
  16. Turn ignition off. Disconnect PCM connector D-108, FTDP sensor connector, intermediate connectors D-112, E-111 and F-07. Check connectors for loose, damaged, or corroded terminals. If problem exists, repair or replace connector(s), reconnect hose "G" then go to step 18. If problem does not exist, repair open circuit in wire between PCM connector D-108 terminal No. 57 and, FTDP sensor connector terminal No. 2, reconnect hose "G". Go to step 18.
  17. Turn ignition off. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to next step. If problem does not exist, go to step 10.
  18. Reconnect all connectors and install all removed components. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAP SYSTEM LEAK MONITOR»(ref-135490-S23094847262002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTCs P0451, P0452 or P0453 are output, replace PCM. If DTCs. If DTCs P0451, P0452 or P0453 are not output, inspection is complete.

Test Conditions A: At Start Up

  1. Intake air temperature is 97°F (36°C) or less when engine started.
  2. Engine coolant temperature was 97°F (36°C) or less when engine started.

Test Conditions B: For Test To Run

  1. Fuel temperature is 97°F (36°C) or less.
  2. Engine coolant temperature is more than 68°F (20°C) when remaining fuel in tank is 40-80 percent (fuel level sensor voltage is 2.4-3.9 volts).
  3. Engine coolant temperature is more than 136°F (58°C) when remaining fuel in tank is 15-40 percent (fuel level sensor voltage is 1.4-2.4 volts).
  4. Engine speed is 1600 RPM or more.
  5. Barometric pressure is more than 11 psi (76 kPa).
  6. Volumetric efficiency is 20-80 percent.
  7. Fuel tank differential pressure sensor output voltage is 1-4 volts.

Test Conditions C: For Test To Stop

  1. Intake air temperature was 41°F (5°C) or less.
  2. EVAP system emission purge solenoid and EVAP emission ventilation solenoid are closed, the pressure rises higher than 0.065 psi (0.451 kPa) when remaining fuel in tank is 15-40 percent (fuel level sensor voltage is 1.4-2.4 volts).
  3. EVAP system emission purge solenoid and EVAP emission ventilation solenoid are closed, the pressure rises higher than 0.047 psi (0.324 kPa) when remaining fuel in tank is 40-85 percent (fuel level sensor voltage is 2.4-3.9 volts).

Code will set if internal pressure of fuel tank changes more than 0.29 psi (2 kPa) after tank and vapor lines are closed. Monitoring time is dependent upon fuel level and temperature in the fuel tank and is 150 seconds.

Note. The following test procedure requires functions available on manufacturer's MUT-II scan tool. Generic scan tools may not have the capability to carry out test.

Note. An improperly tightened fuel cap can cause this code to set. Check for properly installed fuel cap and a good seal between the fuel cap and fuel filler neck.

  1. Ensure transaxle is in Park and fuel cap is securely tightened (3 clicks). Start engine and let idle. Clear DTCs. Using MUT-II scan tool, start EVAP system leak monitor test. Select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. When monitor starts, IN PROGRESS item on scan tool will change from NO to YES. If EVAP LEAK MON. COMPLETED. TEST PASSED is displayed, EVAP system currently is working properly. Code was probably set by improperly installed fuel cap. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, go to next step. If EVAP LEAK MON. DISCONTINUED is displayed, turn ignition off and start monitor over. NOTE: Monitor test will automatically increase engine speed. If engine speed does not reach 1600 RPM or more during monitor test, adjustment of fixed Speed Adjusting Screw (SAS) may be needed. See «FIXED SPEED ADJUSTING SCREW»(ref-135481-S36550359252002022200000) under IDLE SPEED & MIXTURE in ON-VEHICLE ADJUSTMENTS article.
  2. Disconnect hoses "A" and "B" at purge solenoid side. (Scheme 40), (Scheme 41) and (Scheme 42). Connect hand pressure/vacuum pump to purge solenoid port from which hose "B" was disconnected. Turn ignition on. Using scan tool, select actuator test item No. 8 (purge solenoid). When purge solenoid is actuated, using hand pressure/vacuum pump, apply pressure. Verify pressure blows through the other port. If pressure blows through, go to next step. If pressure does not blow through, replace purge solenoid valve. Then go to step 20.
  3. Thoroughly check hoses "A", "B" & "C" for damage, clogging or leaks. If the hoses are OK, go to next step. If hoses are damaged, replace as necessary. Go to step 20
  4. Disconnect hose "T" at ventilation solenoid side. (Scheme 40)and (Scheme 41). Connect hand pressure/vacuum pump to ventilation solenoid port from which hose "T" was disconnected. Turn ignition on. Using scan tool, select actuator test item No. 29 (ventilation solenoid). When ventilation solenoid is actuated, using hand pressure/vacuum pump, apply pressure. Verify pressure is held. If pressure is held, go to next step. If pressure is not held, replace ventilation solenoid valve. Then go to step 20.
  5. Thoroughly check hose "T" for damage, clogging or leaks. If the hose is OK, go to next step. If hose is damaged, replace as necessary. Go to step 20.
  6. Thoroughly check hose "F" for damage, clogging or leaks. (Scheme 40)and (Scheme 41). If the hose is OK, go to next step. If hose is damaged, replace as necessary. Go to step 20.
  7. Confirm Miller EVAP System Pressure Pump (6872A) is operating properly. Perform self-test as described by manufacturer. Pressure test for leaks in the EVAP system between hose "G" to hose "S". Remove fuel cap. Disconnect hose "G" from EVAP canister side and plug. Connect EVAP system pressure pump to fuel filler neck. Perform pressure test (I/M240 simulation test) described in EVAP system pressure pump manufacturer's instructions located in lid of pump box. If leak is indicated, connect hose "G" to EVAP canister and go to next step. If leak is not indicated, go to step 15.
  8. Remove the fuel tank filler neck protector. Disconnect hose "H" from EVAP canister side and connect a hand pressure/vacuum pump. (Scheme 40)and (Scheme 41). Pressurize hose "G" and verify pressure is maintained. If leak is not indicated, go to next step. If leak is indicated, replace defective hose, reinstall filler neck protector and go to step 20.
  9. Thoroughly check hoses "H", "I", "J", "K", "L" M", "N" and "O" for damage clogging or leaks. If the hoses are not damaged or clogged, go to next step. If hoses are damaged so clogged, replace as necessary. Go to step 20.
  10. Inspect check valve "A". (Scheme 40), (Scheme 41) and (Scheme 43). Only when air is blown through the valve in the direction shown in the figure, should it pass air. If the valve is good, go to next step. If the valve is bad, replace valve, reinstall filler neck protector and go to step 20.
  11. Inspect check valve "B". (Scheme 40), (Scheme 41) and (Scheme 44). When air is blown through the valve in the direction shown in the top of figure, should it pass more air as compared to when air blown through valve in the direction shown in the bottom of figure. If the valve is good, go to next step. If the valve is bad, replace valve, reinstall filler neck protector and go to step 20.
  12. Remove fuel tank. Using hand vacuum pump, check hoses "P" and "S" for leaks. (Scheme 40)and (Scheme 41). If leak is indicated, replace appropriate hose, install fuel tank. Go to step 20. If leak does not exist, go to next step.
  13. Visually check fuel tank for cracks and leaks. Connect EVAP system pressure pump to fuel return hose. See. Plug all openings on fuel tank. Using EVAP system pressure pump, pressurize fuel tank. Check for leaks by applying soap to each section of fuel tank. If leak exists, repair leak, install fuel tank and fuel filler neck protector. Go to step 20. If leak does not exist, install fuel tank and fuel filler neck protector. Go to next step.
  14. Ensure transaxle is in Park and fuel cap is securely tightened (3 clicks). Start engine and let idle. Using MUT-II scan tool, start EVAP system leak monitor test. Select SYSTEM TEST and press YES key. Select EVAP LEAK MON and press YES key. When monitor starts, IN PROGRESS item on scan tool will change from NO to YES. If EVAP LEAK MON. COMPLETED. TEST PASSED is displayed, EVAP system currently is working properly. Go to step 20. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, replace PCM and go to step 20. If EVAP LEAK MON. DISCONTINUED is displayed, turn ignition off and start monitor over.
  15. Confirm Miller EVAP System Pressure Pump (6872A) is operating properly. Perform self-test as described by manufacturer. Pressure test and check for clogging in the EVAP system between hose "G" to hose "S". Remove fuel cap. Disconnect hose "G" from EVAP canister and plug. Connect EVAP system pressure pump to fuel filler neck. Perform pressure test (I/M240 simulation test) described in EVAP system pressure pump manufacturer's instructions located in lid of pump box. After verifying pressure is maintained, unplug hose "G" and verify air is blown from hose. If clogging is indicated, go to next step. If leak is not indicated, go to step 20.
  16. Remove the fuel tank filler neck protector. Disconnect hose "H" from EVAP canister side and connect a hand pressure/vacuum pump. Pressurize hose "G" and verify pressure is maintained. If leak is not indicated, go to next step. If leak is indicated, replace defective hose, reinstall hose "H", filler neck protector and go to step 20.
  17. Thoroughly check hoses "H", "I", "J", "K", "L" M", "N" and "O" for damage clogging or leaks. If the hoses are not damaged or clogged, go to next step. If hoses are damaged so clogged, replace as necessary. Go to step 20.
  18. Remove fuel tank assembly. Using hand vacuum pump, check hoses "D" to "E" for leaks or clogging. If leaks or clogging is indicated, replace appropriate hose, install fuel tank assembly. Go to step 20. If leak is not indicated, go to next step.
  19. Remove EVAP canister. Connect hand vacuum pump to canister directly. Plug the other 2 nipples. Apply pressure on the hand pressure/vacuum pump, and confirm the pressure is held. If the pressure is held, go to step 14. If pressure is not held, replace EVAP canister and go to next step.
  20. Test drive vehicle following OBD-II drive cycle EVAP system leak monitor pattern. See «EVAP SYSTEM LEAK MONITOR»(ref-135490-S23094847262002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0455 is output, go to step 1 and retry diagnostic procedure. If DTC P0455 is not output, inspection is complete.

Code will set when the fuel consumption calculated from the operation time of the injector amounts to 20 liters, the difference of the amount of fuel in tank calculated from the fuel level sensor is 2 liters or less.

  1. Turn ignition on. Using scan tool, check data list item No. 4B (fuel level sensor). Fuel level near FULL, voltage displayed should be between 0.1-3.6 volts. Fuel level near EMPTY, voltage displayed should be between 2.7-6.2 volts. If sensor is not operating as specified, go to next step. If scan tool readings are as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000).
  2. Disconnect fuel gauge unit 3-pin connector. see scheme 18 Check fuel gauge unit connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  3. Check continuity between ground and fuel temperature sensor 3-pin connector terminal No. 2 (Black wire). If continuity exists, go to next step. If continuity does not exist, check intermediate 8-pin connector F-07 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07 is OK, repair open in wire between fuel temperature sensor 3-pin connector terminal No. 2 (Black wire) and ground. Then go to step 12.
  4. Disconnect combination meter connector D-03. (Scheme 45) Turn ignition on. Measure voltage between ground and fuel temperature sensor 3-pin connector terminal No. 1 (Yellow/Green wire). There should be battery voltage. If voltage is as specified, go to step 9. If voltage is not as specified, go to next step.
  5. Turn ignition on. Measure voltage between ground and PCM connector D-108 terminal No. 60 (Yellow/Green wire) by backprobing. Fuel level near FULL, voltage displayed should be between 0.1-3.6 volts. Fuel level near EMPTY, voltage displayed should be between 2.7-6.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 7.
  6. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, check intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 for damage and repair as necessary. see scheme 35 If intermediate 8-pin connector F-07, 14-pin connector E-113 and 43-pin connector D-111 are OK, repair Green/Yellow wire between fuel gauge unit 3-pin connector terminal No. 1 and PCM connector D-108 terminal No. 60. Then go to step 12.
  7. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  8. Disconnect fuel gauge unit 3-pin connector. With PCM D-108 connector disconnected, check continuity between ground and fuel gauge unit 3-pin connector terminal No. 1 (Yellow/Green wire). Continuity should not exist. If continuity exists, repair short to ground in wire between fuel gauge unit 3-pin connector terminal No. 3 and PCM connector D-108 terminal No. 60. Then go to step 12. If continuity does not exist, replace PCM, and go to step 12.
  9. Check fuel pump gauge unit. Remove fuel gauge unit from fuel tank. Measure resistance between fuel gauge unit connector terminals No. 1 and 2 (component side) with fuel gauge unit float at full position and at empty position. When fuel gauge unit float is at full position, resistance should be 3-5 ohms. When fuel gauge unit float is at empty position, resistance should be 110-112 ohms. Resistance should smoothly change as fuel gauge unit float is moved from full to empty position. If resistances are not as specified, replace fuel gauge unit. Go to step 12. If resistances are as specified, go to next step.
  10. Disconnect PCM connector D-108. see scheme 28 Check PCM connector D-108 for loose, damaged, or corroded terminals. Also check 8-pin intermediate connector F-07, 14-pin intermediate connector E-113 and 43-pin intermediate connector D-111 for damage and repair as necessary. see scheme 35 If 8-pin intermediate connector F-07, 14-pin intermediate connector E-113 and 43-pin intermediate connector D-111 are OK, repair or replace connector(s). Go to step 12. If problem does not exist, go to next step.
  11. Disconnect fuel gauge unit 3-pin connector. With PCM D-108 connector disconnected, check continuity between PCM D-108 connector terminal No. 60 and fuel gauge unit 3-pin connector terminal No. 1 (Green/Yellow wire). Continuity should exist. Then, check continuity between ground and fuel gauge unit 3-pin connector terminal No. 1 (Green/Yellow wire). Continuity should not exist. If continuity is not as specified, repair open or short to ground in wire between fuel gauge unit 3-pin connector terminal No. 3 (Light Green/Red wire) and PCM connector D-108 terminal No. 60. Then go to next step. If continuity is not as specified, replace PCM, and go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0461 is output, go to step 1, and retry diagnostic procedure. If DTC P0461 is not output, inspection is complete.

Scheme 45

Scheme 45
Scheme 45
  1. DTC P0506 Vehicle speed has reached one MPH at least once. Engine is in closed loop idle speed control. Engine coolant temperature is more than 171°F (77°C). Battery voltage is more than 10 volts. Power steering pressure switch is OFF. Intake air temperature is more than 14°F (-10°C). Volumetric efficiency is less than 40 percent. Barometric pressure is more than 11 psi (76 kPa). 60 seconds have elapsed since the start of previous monitoring. Target idle air control motor position is more than 100 steps. Code will set if actual idle speed is more than 100 RPM lower than target idle speed for 12 seconds.
  1. DTC P0507 Vehicle speed has reached one MPH or more at least once. Engine is in closed loop idle speed control. Engine coolant temperature is more than 171°F (77°C). Battery voltage is more than 10 volts. Intake air temperature is more than 14°F (-10°C). Barometric pressure is more than 11 psi (76 kPa). 60 seconds have elapsed since the start of previous monitoring. Target idle air control motor position is 0 steps. Code will set if actual idle speed is 200 RPM or more higher than target idle speed for 12 seconds, (300 RPM or more for 12 seconds if maximum air temperature during the previous operation was more than 113°F (45°C)).
  1. Check for other DTCs. If any DTC other than P0506 or P0507 is present, diagnose other DTCs first. See appropriate diagnostic tests. If only P0506 or P0507 is present, go to next step.
  2. See NOTE below: NOTE: For DTC P0506, check throttle body, especially throttle valve area for carbon deposits or damage. If throttle valve area is dirty, clean throttle body with solvent. DO NOT allow solvent to enter bypass passage. Start engine and rev to pass solvent through engine until idle can stabilize. Then go to step 14. If throttle valve area is not dirty, go to next step. NOTE: For DTC P0507, check intake system for vacuum leaks. If problem exists, repair vacuum leak. Go to step 14. If problem does not exist, go to next step.
  3. Check IAC motor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  4. Disconnect IAC motor 6-pin connector. Measure resistance between IAC motor connector terminal No. 2 and either terminal No. 1 or 3 (component side). see scheme 23 Measure resistance between IAC motor connector 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 any resistance is not as specified, replace IAC motor assembly. Go to step 14.
  5. Turn ignition on. Measure voltage between ground and IAC motor connector terminal No. 2 (Red wire). Measure voltage between ground and IAC motor connector terminal No. 5 (Red wire). If battery voltage exists at each terminal, go to step 7. If battery voltage does not exist at one or both terminals, go to next step.
  6. Turn ignition off. Remove and check MFI relay connector for loose, damaged, or corroded terminals. see scheme 4 If problem exists, repair or replace connector. Go to step 14. If problem does not exist, repair Red wire between MFI relay and IAC motor. Go to step 14.
  7. Turn ignition off. While turning ignition switch from LOCK position to ON position, measure voltage between ground and PCM connector D-107 terminal No. 14 (Green/Black wire) by backprobing. see scheme 28 Repeat procedure at PCM connector D-107 terminals No. 15 (Green/White wire), No. 28 (Green/Red wire) and No. 29 (Black/Yellow wire). 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 each terminal is as specified, go to step 10. If voltage at any terminal is not as specified, go to next step.
  8. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  9. Connectors still disconnected, check continuity between IAC motor connector and PCM connector D-107. see scheme 23and see scheme 28 and «IAC MOTOR CONNECTOR TO PCM CONNECTOR D-107 TERMINAL DESIGNATIONS»(ref-135490-S35834231942003051200000) for terminal identification. Continuity should exist. Then, check continuity between ground and IAC motor connector terminals. Continuity should not exist. If continuity is not as specified, repair appropriate wire. Go to step 14. If continuity is as specified, replace PCM. Go to step 14. IAC MOTOR CONNECTOR TO PCM CONNECTOR D-107 TERMINAL DESIGNATIONS IAC Motor Connector Terminal No. Wire Color PCM Connector D-107 Terminal No. No. 1 Green/Black No. 14 No. 3 Green/Red No. 28 No. 4 Green/White No. 15 No. 6 Black/Yellow No. 29
  10. Turn ignition off. Check PCM connector D-107 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14. If problem does not exist, go to next step.
  11. Remove IAC motor. Check for IAC motor operation (vibration) when battery positive terminal is jumpered to IAC motor connector terminal No. 2 (component side) and battery negative terminal is jumpered to IAC motor connector terminals No. 1 and 3 (component side). see scheme 23 Check for IAC motor operation (vibration) when battery positive terminal is jumpered to IAC motor connector terminal No. 5 (component side) and battery negative terminal is jumpered to IAC motor connector 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. Go to next step. If IAC motor does not perform as specified, replace IAC motor. Go to step 14.
  12. Turn ignition off. Remove MFI relay. Check continuity between MFI relay connector terminal No. 1 and IAC motor connector terminal No. 2 and 5. Continuity should exist. Then check continuity between ground and MFI relay connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair open or short to ground in Red wire between MFI relay connector terminal No. 1 and IAC motor connector terminal No. 2. Go to step 14. If continuity is as specified, reinstall MFI relay, and go to next step.
  13. With PCM and IAC motor disconnected, check continuity between IAC motor connector and PCM connector D-107. see scheme 23and see scheme 28 and «IAC MOTOR CONNECTOR TO PCM CONNECTOR D-107 TERMINAL DESIGNATIONS»(ref-135490-S35834231942003051200000) for terminal identification. Continuity should exist. Then, check continuity between ground and IAC motor connector terminals. Continuity should not exist. If continuity is not as specified, repair appropriate wire. Go to step 14. If continuity is as specified, replace PCM. Go to step 14.
  14. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P0505 is output, go to step and 1 retry diagnostic procedure. If DTC P0505 is not output, inspection is complete.

Engine coolant temperature is more than 86°F (30°C). Driving and stopping are repeated 10 times or more. Driving is when, for at least 4 seconds, vehicle speed is 31 MPH or more. Stopping is when vehicle speed decreases to less than one MPH. Code will set when power steering pressure switch stays on continuously.

  1. Start engine and let idle. Using scan tool, check data list item No. 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 displays as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000) . If scan tool does not display as specified, go to next step.
  2. Measure voltage between ground and power steering switch 1-pin connector terminal (Yellow wire) by backprobing. With engine idling and steering wheel stationary, battery voltage should exist. With engine idling and steering wheel being turned, voltage should be one volt or less. If voltage is as specified, go to next step. If voltage is not as specified, go to step 5 .
  3. Turn ignition off. Check power steering pressure switch connector for loose, damaged, or corroded terminal. If problem exists, repair or replace connector. Go to step 14 . If problem does not exist, go to next step.
  4. Start engine and let idle. Using scan tool, check data list item No. 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 displays as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000) . If scan tool does not display as specified, replace PCM. Go to step 14 .
  5. Turn ignition off. Check power steering pressure switch connector for loose, damaged, or corroded terminal. If problem exists, repair or replace connector. Go to step 14 . If problem does not exist, go to next step.
  6. Disconnect power steering pressure switch connector. Turn ignition on. Check voltage between ground and power steering pressure switch connector (Yellow wire). If battery voltage exists, go to step 11 . If battery voltage does not exist, go to next step.
  7. Measure voltage between ground and PCM connector D-108 terminal No. 52 (Yellow wire) by backprobing. If battery voltage exists, go to next step. If battery voltage does not exist, go to step 9 .
  8. Turn ignition off. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14 . If problem does not exist, repair open in Yellow wire between PCM and power steering pressure switch. Go to step 14 .
  9. Turn ignition off. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14 . If problem does not exist, go to next step.
  10. Check continuity between PCM connector D-108 terminal No. 52 and power steering pressure switch connector. If continuity does not exist, repair Yellow wire. Go to step 14 . If continuity exists, replace PCM. Go to step 14 .
  11. Replace power steering pressure switch. Test drive vehicle following DTC P0551 set criteria. See «DTC SET CRITERIA»(ref-135490-S00441302842002022200000) . Check for DTCs. If DTC P0551 is output, go to next step. If DTC P0551 is not output, go to step 14 .
  12. Turn ignition off. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 14 . If problem does not exist, go to next step.
  13. Check continuity between PCM connector D-108 terminal No. 52 and power steering pressure switch connector. If continuity does not exist, repair Yellow wire. Go to next step. If continuity exists, replace PCM. Go to next step.
  14. Start engine and let idle. Using scan tool, check data list item No. 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 displays as specified, inspection is complete. If scan tool does not display as specified, go to step 1 and retry diagnostic procedure.
  1. If engine coolant temperature was less than 32°F (0°C) when engine was started, at least 8 minutes have since passed. Engine coolant temperature is more than 113°F (45°C). Intake air temperature is more than 32°F (0°C). Volumetric efficiency is 30-55 percent. Code will set when MDP sensor output voltage is more than 4.6 volts, or less than 0.1 volt, for 2 seconds.
  2. If engine coolant temperature was less than 32°F (0°C) when engine was started, at least 8 minutes have since passed. Engine coolant temperature is more than 113°F (45°C). Intake air temperature is more than 41°F (5°C). Volumetric efficiency is less than 30 percent. Code will set when MDP sensor output voltage is more than 4.2 volts for 2 seconds.
  3. If engine coolant temperature was less than 32°F (0°C) when engine was started, at least 8 minutes have since passed. Engine coolant temperature is more than 113°F (45°C). Intake air temperature is more than 41°F (5°C). Volumetric efficiency is more than 70 percent. Code will set when MDP sensor output voltage is less than 1.8 volts for 2 seconds.
  1. Start engine and warm up to normal operating temperature. Using scan tool, check data list item No. 95 (manifold differential pressure sensor). With engine idling, scan tool should display 21.3-34.7 kPa. If scan tool displays as specified, problem is intermittent. See «INTERMITTENT DIAGNOSTIC TROUBLE CODES»(ref-135490-S13352502652002022200000). If scan tool does not display as specified, go to next step.
  2. Turn ignition off. Check MDP sensor connector for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  3. Disconnect MDP sensor 3-pin connector. Turn ignition on. Measure voltage between ground and MDP sensor connector terminal No. 3 (Green/Yellow wire). see scheme 25 Voltage should be 4.8-5.2 volts. If voltage is as specified, go to step 6. If voltage is not as specified, go to next step.
  4. Turn ignition off. Disconnect and check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  5. Check continuity between MDP sensor connector terminal No. 3 and PCM connector D-108 terminal No. 46 (Green/Yellow wire). see scheme 25and see scheme 28. Continuity should exist. Then, check continuity between ground and MDP sensor connector terminal No. 3 (Green/Yellow wire). Continuity should not exist. If continuity is not as specified, repair open or short circuit in Green/Yellow wire. Go to step 12. If continuity is as specified, replace PCM. Go to step 12.
  6. Turn ignition off. Check for continuity between ground and MDP sensor connector terminal No. 2 (Black wire). If continuity exists, go to step 9. If continuity does not exist, go to next step.
  7. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  8. Check continuity between MDP sensor connector terminal No. 2 and PCM connector D-108 terminal No. 57 (Black wire). see scheme 25and see scheme 28. If continuity does not exist, repair Black wire. Go to step 12. If continuity exists, replace PCM. Go to step 12.
  9. Disconnect and check PCM connector D-109 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 12. If problem does not exist, go to next step.
  10. Check continuity between MDP sensor connector terminal No. 3 and PCM connector D-108 terminal No. 46. Continuity should exist. Then, check continuity between ground and MDP sensor connector terminal No. 3 Continuity should not exist. If continuity is not as specified, repair open or short circuit in Green/Yellow wire. Go to step 12. If continuity is as specified, go to next step.
  11. Check continuity between MDP sensor connector terminal No. 1 and PCM connector D-109 terminal No. 91. Continuity should exist. Then, check continuity between ground and MDP sensor connector terminal No. 1. Continuity should not exist. If continuity is not as specified, repair open or short circuit in Blue/Yellow wire. Go to next step. If continuity is as specified, replace MDP sensor. Go to next step.
  12. Test drive vehicle following OBD-II drive cycle Other Monitor pattern. See «OTHER MONITOR»(ref-135490-S39720580962002022200000) under OBD-II DRIVE CYCLES under VERIFYING REPAIRS. Check for DTCs. If DTC P1400 is output, go to step 1 and retry diagnostic procedure. If DTC P1400 is not output, inspection is complete.

Starting sequence was completed. Battery positive voltage is higher than 10 volts. Code will set when battery backup line voltage has continued to be less than 6 volts for 2 seconds.

  1. Using Scan tool check for DTC P1603. Erase the DTC. Start engine and run at idle. Check for DTC P1603. If DTC P1603 is present, go to next step. If DTC P1603 is not output, inspection is complete.
  2. Turn ignition on. Measure voltage between ground and PCM connector D-108 terminal No. 66 (Red/Black wire) by backprobing. Battery voltage should exist. If voltage is as specified, go to step 5 . If voltage is not as specified, go to next step.
  3. Disconnect PCM connector D-108. Turn ignition on. Measure voltage between ground and PCM connector D-108 terminal No. 66 (Red/Black wire). Battery voltage should exist. If voltage is as specified, go to next step. If voltage is not as specified, check 33-pin intermediate connector D-02, 38-pin intermediate connector D-28 and 38-pin intermediate connector E-111 for loose, damaged or corroded terminals. If problem does not exist with intermediate connector(s), repair open or short to ground in Red/Black wire between battery and PCM connector D-108 terminal No. 66. Then go to step 6 .
  4. Check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to step 6 . If problem does not exist, check 33-pin intermediate connector D-02, 38-pin intermediate connector D-28 and 38-pin intermediate connector E-111 for loose, damaged or corroded terminals. If problem does not exist with intermediate connector(s), repair Red/Black wire between battery and PCM connector D-108 terminal No. 66. Then go to step 6 .
  5. Disconnect and check PCM connector D-108 for loose, damaged, or corroded terminals. If problem exists, repair or replace connector. Go to next step. If problem does not exist, replace PCM and go to next step.
  6. Turn ignition on. Using Scan tool check for DTC P1603. Check for DTC P1603. If DTC P1603 is present, go to step 1 and retry diagnostic procedure again. If DTC P1603 is not output, inspection is complete.
  1. Ignition is on. Code will set when communication error between Powertrain Control Module (PCM) and immobilizer ECU continues for 2 seconds or more.
  2. Ignition is on. Code will set when PCM receives signal from immobilizer ECU to prohibit engine from starting.

Using scan tool, check for immobilizer system DTCs. If immobilizer system DTC is present, diagnose immobilizer system concern. See IMMOBILIZER SYSTEMS - MONTERO article under ACCESSORIES & EQUIPMENT. If immobilizer system DTC is not present, erase Multiport Fuel Injection (MFI) DTCs and retest system. If DTC P1610 sets again, replace PCM.

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