Engine Controls - Self-Diagnostics: Diagnosis Mazda Tribute I

SELF-DIAGNOSTIC SYSTEM

Note. Mazda Tribute has similar diagnostic and testing procedures as the Ford Escape. This article may have references to Ford Escape articles.

Note. Manufacturer recommends using World Diagnostic System (WDS) or equivalent scan tool. WDS testers or equivalent scan tools are referred to as scan tool in diagnostic information.

KOEO & KOER Self-Test

KOEO DTCs are set when a KOEO self-test is performed. KOEO self-test is a functional test of powertrain control module performed on demand with key on and engine off. KOEO self-test will perform checks on certain sensor and actuator circuits. A fault must be present at time of testing for KOEO self-test to detect fault. When a fault is detected, a DTC will be output on data link at end of test when requested by scan tool.

KOER DTCs are set when a KOER self-test is performed. KOER self-test is a function test of powertrain control module performed on demand with key on and engine running. A check for certain inputs and outputs is made during operating conditions at normal temperature. Brake pedal position, Transaxle Control Switch (TCS) and power steering switch tests are part of KOER self-test and must be performed during this operation if applicable. A fault must be present at time of performing KOER self-test to detect fault. When a fault is detected, DTC will be output on data link at end of test when requested by scan tool.

Brake pedal position test checks ability of Powertrain Control Module (PCM) to detect a change of state in stoplight switch. Transaxle Control Switch (TCS) test checks ability of PCM to detect a change of state in overdrive OFF switch. Power steering switch test checks ability of PCM to detect a change of state in power steering fluid pressure.

Continuous Memory Self-Test

Continuous memory DTCs are set when a continuous memory self-test is performed. Continuous memory self-test is a functional test of PCM performed under any condition (engine running or off) with ignition on. Unlike KOEO and KOER self-tests which can only be activated on demand, continuous memory self-test is always active in monitoring the system. When a fault is detected, DTC will be stored in memory. This makes it possible to diagnose intermittent faults.

There are 2 types of continuous memory DTCs. First type is emission-related and will illuminate the Malfunction Indicator Light (MIL) located in instrument cluster. The second is a non-emission related and will never illuminate MIL.

For emission-related MIL codes, Powertrain Control Module (PCM) will store DTC in continuous memory when a fault is detected for the first time. At this point, DTC will not illuminate MIL and is considered a pending code. If same fault is detected after next ignition start-run cycle, emission-related code will illuminate the MIL. The MIL will remain on even if fault is intermittent. The MIL will be turned off if fault is not present through 3 consecutive drive cycles, or if PCM reset is performed. Also, an emission-related pending code and non-emission related codes will be erased after about 40-80 vehicle warm up cycles or PCM reset.

Brake On/Off Test

This tests the ability of the PCM to identify a state of change in the stoplight switch. The brake pedal must briefly be applied and released on all vehicles with a brake on/off input. This test is performed during the KOER self-test.

Transaxle Control (O/D OFF) Switch Test

This tests the ability of the PCM to identify a state of change in the O/D OFF switch. The switch must briefly be cycled on all vehicles with an O/D OFF switch. This test is performed during the KOER self-test.

Power Steering Pressure (PSP) Switch Test

This tests the ability of the PCM to identify a state of change in the power steering fluid pressure. The steering wheel must briefly be turned at least 1/4 turn. This test is done during the KOER self-test.

QUICK TEST

Note. Manufacturer recommends using World Diagnostic System (WDS) or equivalent scan tool. WDS testers or equivalent scan tools are referred to as scan tool in diagnostic information. Manufacturer has a specific procedure that must be followed during DTC retrieval. Failure to follow procedures, may result in incorrect diagnosis. Retrieve data types in order as identified.

Scheme 39

1. Record Continuous Memory DTC & Freeze Frame Data Turn ignition on with engine off. Connect scan tool to DLC. (Scheme 39) Retrieve all stored DTCs. Observe and record all DTCs and freeze frame data. Go to next step.
2. Verify Related Repair Information Check for any related Technical Service Bulletins (TSBs). If any TSBs apply, perform indicated repair. If vehicle is now repaired, procedure is complete. If no TSBs apply, go to next step.
3. Perform Key On Engine Off (KOEO) Self-Test Start engine and allow to reach normal operating temperature. Turn off all electrical accessories. Perform KOEO self-test procedure. If any DTCs are present, go to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, go to next step.
4. Perform Key On Engine Running (KOER) Self-Test Start engine. Perform KOER self-test procedure. If any DTCs are present, go to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, go to next step.
5. If Continuous Memory DTCs are present in first step, go to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If Continuous Memory DTCs are not present, proceed to «TROUBLE SHOOTING - NO CODES»(ref-134968) article for diagnosis by symptom.

INTERMITTENT DIAGNOSTICS

Intermittent diagnostics help find and isolate the cause of intermittent faults. Start with recreating a fault symptom and accumulating PCM data and comparing data to typical values. Analyze the results. Verify good engine and drivetrain mechanical conditions. Check any available Technical Service Bulletins (TSBs) and perform necessary repairs. Perform QUICK TEST under SELF-DIAGNOSTIC SYSTEM and referenced DTC tests. If after diagnosis, symptom is still present, it is necessary to attempt to re-create the fault. Start with customer's information and description of symptom. If freeze frame data is available, it will be valuable in recreating conditions when fault occurred. See RE-CREATING FAULT CONDITIONS table. Gather as much PCM PID data as possible. PID data should be gathered during different vehicle operating conditions as well as under conditions described by customer. Compare PCM PID data to known good data values. Examine PCM PID data for abnormal events or clearly incorrect values. Inspect signals for unexpected or abrupt changes. Cross check for agreement between related signals. See PIN VOLTAGE/PID VALUE CHARTS article.

RE-CREATING FAULT CONDITIONS

TEST EQUIPMENT

All voltage tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless specifically stated differently in testing procedure. When instructed to use a fused jumper wire, ensure fused jumper wire is equipped with an in-line 5-amp fuse.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

If a DTC appears with an "x" in the numerator (example DTC P071x), "x" denotes any number between 0-9. If a "P" series DTC appears that is not listed in DIAGNOSTIC TROUBLE CODE DEFINITIONS table, diagnose by symptom in TROUBLE SHOOTING - NO CODES article. On some models, PCM is capable of storing some body DTCs. If any "B", "C" or "U" series DTCs are retrieved (example DTC B1213, C1702 or U2195) that are not list in DIAGNOSTIC TROUBLE CODE DEFINITIONS table, go to appropriate MODULE COMMUNICATIONS NETWORK article in ACCESSORIES & EQUIPMENT to determine test to perform.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DIAGNOSTIC TESTS

Note. For connector terminal identification, see WIRING DIAGRAMS article. Always perform applicable drive cycle test after repair is performed to verify if DTC is reset.

Diagnostic Procedures

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. DTCs P0131 & P0151: Contaminated HO2S/Voltage Shift DTC P0131 (right front HO2S-11) and DTC P0151 (left front HO2S-21). For HO2S locations (Scheme 40) Check for water in HO2S 4-pin harness connectors. If water is not present in connector, go to next step. If water is present in HO2S connector, dry out connector and repair source of water leak. If problem cannot be repaired, replace HO2S. After repair, go to step 4.
3. Verify Wiring Is In Proper Pin Location Disconnect 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of HO2S SIG circuit between breakout box terminal No. 60 (DTC P0131) or No. 87 (DTC P0151) and HO2S 4-pin harness connector. (Scheme 41) Record measurement. Measure resistance of SIG RTN circuit (Orange wire) between breakout box terminal No. 91 and HO2S 4-pin harness connector. Record measurement. If resistance reading is 5 ohms or more, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to next step. If resistance reading is less than 5 ohms, replace suspect HO2S. After repair, go to next step.
4. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, procedure is complete.

Scheme 40

Scheme 41

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Check For Source Of Potential HO2S Contamination Investigate following items as potential sources of HO2S contamination: Use of unapproved silicone sealers. Fuel contaminated with silicone additives. Excessive oil burning (i.e., rings, valve seals and/or oil overfill). Engine coolant leaking internally in the engine. Lead contaminated fuel. Short drive cycles in cold weather. Use of unapproved cleaning agents. If all of these conditions are not present, go to next step. If any of these conditions are present, repair source of contamination. Replace HO2S and change oil and filter. For HO2S locations (Scheme 40) After repair, go to step 8.
3. Check For Unmetered Air Leaks Fuel calculations can be affected by unmetered air leaks. Carefully inspect the following areas for potential air leaks: Hoses connecting MAF/IAT sensor assembly. Hoses connecting to throttle body. Intake manifold gasket leaks. PCV disconnected. Vacuum lines disconnected. Improperly seated dipstick tube and oil filler cap. Exhaust leaks at flanges and gaskets. If no air leaks are present, go to next step. If any air leaks are present, repair source of leak. After repair, go to step 8.
4. Check HO2S Circuit Wiring With PCM Connected Connect scan tool to DLC. Disconnect suspect HO2S 4-pin harness connector. Connect fused jumper wire between HO2S 4-pin harness connector HO2S SIG terminal and VPWR terminal. Turn ignition on, engine off. Access O2S11 for P0133 or O2S21 for P0153 and note voltage reading. If voltage reading is more than 1.50 volts, go to next step. If voltage reading in 1.5 volts or less, remove fused jumper wire and go to step 6.
5. Check For Short To VPWR And VREF Disconnect scan tool from DLC. Turn ignition on, engine off. Measure voltage between suspect HO2S 4-pin harness connector HO2S SIG terminal and SIG RTN terminal. If voltage reading is less than 4.5 volts, replace HO2S and change oil and filter. For HO2S locations (Scheme 40) After repair, go to step 8. If voltage reading is 4.5 volts or less, repair short in VPWR or VREF circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
6. Check Resistance Of HO2S Signal Circuit Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of the HO2S SIG circuit between breakout box terminal No. 60 (DTC P0133) or No. 87 (DTC P0153) and HO2S 4-pin harness connector. (Scheme 41) Record measurement. Measure resistance of SIG RTN circuit (Orange wire) between breakout box terminal No. 91 and HO2S 4-pin harness connector. Record measurement. If each resistance reading is less than 5 ohms, go to next step. If each resistance reading is 5 ohms or more, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
7. Check For Short To Ground Disconnect scan tool from DLC. For P0133 (Front), measure resistance between breakout box terminals: No. 60 (HO2S SIG) and No. 91 (SIG RTN) for sensor ground. No. 60 (HO2S SIG) and No. 71 (PWR GND). For P0153 (Front), measure the resistance between breakout box terminals: No. 87 (HO2S SIG) and No. 91 (SIG RTN) for sensor ground. No. 87 (HO2S SIG) and No. 71 (PWR GND). If resistance reading is 10,000 ohms or less, go to next step. If resistances reading is more than 10,000 ohms, replace PCM. After repair, go to next step.
8. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform Fuel Monitor or HO2S Monitor Drive Cycle. Refer to «HO2S MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S32081150652002112700000) or «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. Retrieve pending code. If same DTC is present, replace PCM. After repair, go to next step. If same DTC is not present, go to next step.
9. Verify Trouble Shooting Of DTCs Completed Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and KOEO DTC P0135, P0141, P0155 and P0161 were not present, fault may be intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000). If same DTCs were present, go to next step.
2. Visual Inspection Visually inspect suspect HO2S circuit for exposed wiring, contamination, corrosion and proper assembly. If no concerns were found during visual inspection, go to next step. If any concerns were found during visual inspection, repair as necessary. After repair, go to step 8.
3. Check For VPWR At Vehicle Harness Connector If DTCs P0135 and P0155, P0141 or P0161 are displayed, both heater circuits will require testing. DTCs displayed separately are tested individually. Disconnect appropriate HO2S 4-pin harness connector(s). Turn ignition on, engine off. Measure voltage between HO2S 4-pin harness connector(s) VPWR terminal (Light Blue/Orange wire) and SIG RTN terminal (Orange wire). If voltage reading is more than 10.5 volts, go to next step. If voltage reading is 10.5 volts or less, check No. 5 FUEL PUMP fuse (15-amp) in engine compartment fuse/relay box. If fuse is okay, repair open Light Blue/Orange between No. 5 FUEL PUMP fuse (15-amp) and suspect HO2S 4-pin harness connector. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
4. Check HO2S Heater Resistance Disconnect suspect HO2S 4-pin harness connector. Measure resistance of HO2S HTR GND at component connector. For DTC P0135 (Red/White wire), P0141 (White/Black wire), P0155 (Yellow/Light Blue wire) or P0161 (Tan/Yellow wire). (Scheme 40)and (Scheme 41). If resistance reading is 3-30 ohms, go to next step. If resistance reading is not as specified, replace suspect HO2S. After repair, go to step 8.
5. Check For HTR GND & VPWR Shorted To HO2S Case Measure resistance between HO2S HTR GND terminal at HO2S component connector and HO2S case. Measure resistance between HO2S HTR GND terminal and SIG RTN terminal (Orange wire) at HO2S component connector. Measure resistance between HO2S VPWR terminal (Light Blue/Orange wire) at HO2S component connector and HO2S case. If resistance readings are more than 10,000 ohms, go to next step. If resistance reading is 10,000 ohms or less, replace suspect HO2S. After repair, go to step 8.
6. Check For Shorts To Other Grounds & VPWR In HO2S HTR GND Harness Circuits Disconnect scan tool from DLC. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Use list to measure resistance between appropriate breakout box terminals: For DTC P0135, terminal No. 93 and terminals No. 71, 91 and 103. For DTC P0141, terminal No. 100 and terminals No. 71, 91 and 103. For DTC P0155, terminal No. 94 and terminals No. 71, 91 and 103. For DTC P0161, terminal No. 96 and terminals No. 71, 91 and 103. If resistance reading is more than 10,000 ohms, go to next step. If resistance reading is 10,000 ohms or less, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
7. Check For Open HO2S HTR GND Harness Circuit Use following list to measure resistance between appropriate breakout box (HTR GND) terminal and HO2S 4-pin harness connector HTR GND terminal: For DTC P0135, breakout box terminal No. 93. For DTC P0141, breakout box terminal No. 100. For DTC P0155, breakout box terminal No. 94. For DTC P0161, breakout box terminal No. 96. If resistance reading is less than 4.0 ohms, open, shorted or excessive resistance in HTR circuit in PCM. Replace PCM. After repair, go to next step. If resistance reading is 4.0 ohms or more, repair open or excessive resistance in HTR GND circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to next step.
8. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, procedure is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and Continuous Memory Ignition (P0350-P0354) or Misfire (P0300-P0306) DTCs were received during Continuous Memory Testing, repair those DTCs first. If Continuous Memory DTCs were not present, go to next step.
2. Check For HO2S KOER If DTCs P1137, P1138, P1157 or P1158 were present during PCM Quick Test, go to next step. If DTCs P1137, P1138, P1157 or P1158 were not present, Fault that produced DTC P0136 or P0156 is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
3. Visual Inspection Checked for pinched, corroded or stretched wires. Any exhaust leaks between engine and end of catalyst can cause DTC P0136 or P0156 with P1137 and/or P1138 or P1157 and/or P1158. Inspect following: Check for punctures and cracks in catalyst and pipes leading to them. Check exhaust flanges for leaks. Check HO2S torque. If any of these possible causes are present, repair as necessary. After repair, go to step 10.
4. Check HO2S Harness For Short To VPWR & Ground Disconnect scan tool from DLC. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Disconnect suspect rear HO2S 4-pin harness connector. Measure resistance between breakout box terminal No. 35 (Bank 1) or terminal No. 60 (Bank 2) and following breakout box terminals: No. 91 (short to SIG RTN) No. 71 (short to VPWR) No. 90 (short to VREF) No. 103 (short to PWR GND) If each resistance reading is more than 10,000 ohms, go to next step. If resistance reading is 10,000 ohms or less, repair short in harness. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 10.
5. Check Resistance Of HO2S SIG & Ground Circuits For Open In Harness Measure resistance of HO2S SIG circuit between breakout box terminal No. 35 (Bank 1) or terminal No. 60 (Bank 2) and HO2S 4-pin harness connector. Record reading. Measure resistance of HO2S SIG RTN circuit between breakout box terminal No. 91 and HO2S 4-pin harness connector. (Scheme 40)and (Scheme 41). Record reading. If both resistance readings are less than 5 ohms, go to next step. If either resistance reading is 5 ohms or more, repair open HO2S SIG circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 10.
6. Check HO2S Circuit Voltage Remove Breakout Box. Reconnect PCM 104-pin harness connector and rear HO2S 4-pin harness connector. Reconnect scan tool to DLC. Turn ignition on, engine off. Access O2S12 PID (Bank 1) or O2S22 PID (Bank 2) and record reading. If voltage reading was 1.5 volts or less, go to next step. If voltage reading was more than 1.5 volts, go to step 9.
7. Check Resistance Of HO2S Ground Circuit In PCM Turn ignition off. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM only, leave harness connector disconnected. see scheme 2 Measure resistance between breakout box terminals No. 91 (SIG RTN) and No. 103 (PWR GND). If resistance reading is less than 5 ohms, go to next step. If resistance reading is 5 ohms or more, replace PCM. After repair, go to step 10.
8. Apply 12 Volts To Suspect HO2S Circuit Remove Breakout Box. Reconnect PCM 104-pin harness connector to PCM. Disconnect suspect rear HO2S 4-pin harness connector. Connect fused jumper wire between HO2S 4-pin harness connector VPWR terminal (Light Blue/Orange wire) and HO2S SIG terminal. Turn ignition on, engine off. Access O2S12 PID (Bank 1) or O2S22 PID (Bank 2) and monitor. If PID reading is more than 1.5 volts, replace rear HO2S. After repair, go to step 10. If PID reading in 1.5 volts or less, replace PCM. After repair, go to step 10.
9. Check For Over Voltage On HO2S Circuit In PCM Turn ignition on, engine off. Disconnect suspect rear HO2S 4-pin harness connector. Measure voltage between HO2S 4-pin harness connector SIG RTN terminal (Orange wire) and negative battery terminal. Record reading. Measure voltage between HO2S 4-pin harness connector HO2S SIG terminal and negative battery terminal. If either voltage reading is more than 1.5 volts, replace PCM. After repair, go to next step. If either voltage reading is 1.5 volts or less, replace rear HO2S. After repair, go to next step.
10. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, procedure is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and Continuous Memory Misfire (P0300-P0306) DTCs were received during Continuous Memory Testing or driveability concern is present, go to step 6 . If Continuous Memory DTCs were not present, go to next step. If any other DTC is present, go to appropriate DTC inspection. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If Continuous Memory DTCs were not present, go to next step.
2. Identify Trigger DTC For FREEZE FRAME DATA If DTC P0171 or P0174 are on FREEZE FRAME DATA, go to next step. If DTC P0171 or P0174 are not on FREEZE FRAME DATA, go to trouble shooting procedure for DTC that triggered FREEZE FRAME DATA.
3. Verify Current Input Signal Status Start engine. Access ECT V, MAF/IAT V, TP V and VSS PIDs using scan tool. If there is any signal that is far out of specification during KOER, check suspect sensor for excessive resistance in related harnesses. Repair as necessary. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 14 . If no sensor signals are out of specification, go to next step.
4. Verify Current Input Signal Status Under Trouble Condition Access ECT V, MAF/IAT V, TP V and VSS PIDs while simulating FREEZE FRAME DATA condition. If there is any input signal which causes drastic changes, Check suspect sensor and related wiring harnesses. Repair or replace as necessary. After repair, go to step 14 . If there are no input signals which cause drastic changes, go to next step.
5. Verify Current Input Signal Status Of Front HO2S (RH, LH) Access O2S11 PID for P0171 or O2S21 PID for P0174. Check PID under following accelerator pedal condition (in Park): Sudden depress of accelerator pedal (rich condition) should read more than 0.45 volt. Sudden release of accelerator pedal (lean condition) should read less than 0.45 volt. If PID is reading correctly, check for air leaks at following areas due to cracks, damaged and loose parts: From air cleaner to throttle body. From throttle body to dynamic chamber. From dynamic chamber to intake manifold. Vacuum hoses Engine speed may change when rust penetrating agent is sprayed on the air suction area. Repair or replace any faulty part. After repair, go to step 14 . Visually inspect for any exhaust leakage between exhaust manifold and H20S. If there is no leakage, replace HO2S. After repair, go to step 14 .
6. Inspect MAF/IAT V PID Start engine. Access MAF/IAT V PID using scan tool. Race engine. Ensure that MAF/IAT V PID changes quickly according to racing engine RPM. If MAF/IAT V PID response is okay, go to next step. If MAF/IAT V PID response is not okay, replace MAF/IAT sensor. After repair, go to step 14 .
7. Inspect For Excessive Air Suction Of Intake Air System Visually inspect air intake system for cracks, damage, or loose parts. If problem is found, repair source of air leak. After repair, go to step 14 . If no problem is found, go to next step.
8. Inspect Fuel Line Pressure Turn ignition off. Connect fuel pressure gauge. Start engine. If fuel pressure reading is 55-70 psi (380-482 kPa), go to step 12 . If fuel pressure is not as specified, go to next step.
9. Inspect Fuel Pump Circuit Turn ignition off. Check fuel pump circuit for open or poor connection. See «WIRING DIAGRAMS»(ref-134975) article. If circuit is okay, go to next step. If fuel pump circuit is not okay, repair suspect circuit as necessary. After repair, go to step 14 .
10. Inspect Fuel Line From Fuel Pump To Fuel Delivery Line Visually inspect fuel line for any leakage. If no fuel leaks are found, go to next step. If any fuel leakage is found, replace fuel line. After repair, go to step 14 .
11. Inspect Fuel Filter Inspect fuel filter for: Restriction or clogging at high pressure side. Foreign material or stains at low pressure side. If any condition or fault is found on high pressure side, replace fuel filter. If problem is found on low pressure side, clean fuel tank and low pressure filter. After repair, go to step 14 . If no condition or fault is found, replace fuel pump. After repair, go to step 14 .
12. Inspect Engine Compression Perform an Engine Compression test. If compression readings are okay, go to next step. If engine compression is not okay, overhaul engine.
13. Inspect Fuel Injector Operation Remove injector from suspected bank and swap with injector from other bank. Start engine. Using scan tool, monitor FREEZE FRAME DATA. If fuel trim system is lean for bank which has suspected injector, Turn ignition off. Replace fuel injector. After repair, go to next step. If fuel trim system is not lean for bank which has suspected injector, go to next step.
14. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) or «HO2S MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S32081150652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If same DTC is present, replace faulty PCM. If same DTC is not present, go to next step.
15. Verify Trouble Shooting Of DTCs Completed Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and driveability concern or rough idle is present, go to step 7 . If any other DTC is present, refer to appropriate DTC test under «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If Continuous Memory DTCs were not present, go to next step.
2. Identify Trigger DTC For FREEZE FRAME DATA If DTC P0171 or P0174 are on FREEZE FRAME DATA, go to next step. If DTC P0172 or P0175 are not on FREEZE FRAME DATA, go to trouble shooting procedure for DTC that triggered FREEZE FRAME DATA.
3. Verify Current Input Signal Status Start engine. Access ECT V, MAF V, TP V and VSS PIDs as well as BARO and LONGFT using scan tool. If no signal is far out of specification, go to next step. If any signal is far out of specification during KOER, check suspect sensor and related wiring harnesses for excessive resistance. See «WIRING DIAGRAMS»(ref-134975) article. Repair as necessary. After repair, go to step 9 .
4. Verify Current Input Signal Status Under Trouble Condition Access ECT V, MAF V, TP V and VSS PIDs while simulating FREEZE FRAME DATA condition. If there is any input signal which causes drastic changes, check condition of suspect sensor and related wiring harnesses. Repair as necessary. After repair, go to step 9 . If no input signal caused any drastic changes, go to next step.
5. Verify Current Input Signal Status Of Front HO2S Access O2S11 PID for P0172 or O2S21 PID for P0175. Check PID under following accelerator pedal condition (in PARK position): Sudden depress of accelerator pedal (rich condition) should read more than 0.45 volt. Sudden release of accelerator pedal (lean condition) should read less than 0.45 volt. If both PIDs are reading correctly, go to next step. If either PID read is incorrect, replace HO2S. After repair, go to step 9 .
6. Inspect Fuel Line Pressure Turn ignition off. Connect fuel pressure gauge. Start engine. If fuel pressure reading is 55-70 psi (380-482 kPa), go to next step. If fuel pressure is not as specified, refer to «FUEL DELIVERY SYSTEM»(ref-150940-S38917645432002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000) . After repair, go to step 9 .
7. Inspect EVAP Canister Purge Valve Turn ignition off. Disconnect both hoses from EVAP canister purge valve. Blow air through EVAP canister purge valve. If air passes through valve, replace EVAP canister purge valve. After repair, go to step 9 . If air does not pass through valve, go to next step.
8. Inspect PCV Valve Operation Inspect PCV valve for proper operation. If PCV valve is okay, go to next step. If PCV valve is not okay, replace PCV valve. After repair, go to next step.
9. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) or «HO2S MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S32081150652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If same DTC is present, replace faulty PCM. If same DTC is not present, go to next step.
10. Verify Trouble Shooting Of DTCs Completed Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and any other DTCs are present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If DTC P0300 only is present, go to step 18. If DTCs P0300 and P0301-P0306 are present, go to next step.
2. Check/Compare PID Values Turn all accessories off (A/C, heater, etc.). Turn Key On, Engine Off (KOEO). Access DPFEGR PID with scan tool and record values. Turn Key On, Engine Running (KOER). Compare KOEO and KOER PID values. Turn ignition off. If difference between PID values is not within 0.15 volt, go to next step. If difference between PID values is within 0.15 volt, go to step 4. NOTE: Perform KOER Self-Test and repair any DTCs before proceeding with this test.
3. Check Operation Of EGR Valve The symptom indicates possible EGR flow at idle with no EGR DTCs output. Possible causes: EGR valve not fully seating. EGR vacuum regulator solenoid vent restricted. Damaged EGR vacuum regulator solenoid. Disconnect vacuum hose at EGR valve and plug hose. Turn ignition on, engine off. Access DPFEGR PID with scan tool and record voltage. Start engine. With engine at idle, look at DPFEGR PID voltage reading and compare to engine off reading. An increase in voltage reading at idle indicates that DPFEGR sensor is sensing EGR flow. Turn ignition off. If DPFEGR PID voltage reading was more at idle by a minimum of 0.15 volt than with engine off, DPFEGR PID voltage reading indicates EGR flow at idle. Since vacuum hose to EGR is disconnected and plugged, fault is most likely in EGR valve. Remove and inspect EGR valve for signs of contamination, unusual wear, carbon deposits binding or other damage. Repair as necessary. After repair, go to step 20. If DPFEGR PID voltage reading was not as specified, a fault in EGR vacuum supply is indicated. Inspect EGR Vacuum Regulator (EGRVR) solenoid vent and vent filter for restrictions. Repair as necessary. If no restrictions are found, replace EGRVR solenoid. After repair, go to step 20. WARNING: Fuel system will remain pressurized when engine is not running. To prevent injury or fire, use caution when working on fuel system.
4. Check Fuel Pressure Install fuel pressure gauge. Start engine. Note fuel pressure. Increase engine speed to 2500 RPM and maintain for 1 minute. Note and compare fuel pressure. Turn ignition off. If fuel pressure was 55-70 psi (380-482 kPa) and it remained at specification within 5 psi (35 kPa) for 60 seconds, go to next step. If fuel pressure was not as specified, refer to «FUEL DELIVERY SYSTEM»(ref-150940-S38917645432002120200000) testing.
5. Check Injector Driver PIDS INJ1F Through INJ6F Turn ignition on, engine off. Access appropriate PID(s) for suspect fuel injector. If PID status is YES, go to next step. If PID status is NO, go to step 9.
6. Check Resistance Of Fuel Injector(s) & Harness Turn ignition off. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of INJ circuit between breakout box terminal No. 71 or 97 and suspect fuel injector breakout box terminal. See «BREAKOUT BOX INJECTOR TERMINAL IDENTIFICATION»(ref-150940-S28116256382003011500000) table. If resistance reading is 11-18 ohms, replace PCM. After repair, go to step 9. If resistance reading is not as specified, go to next step. BREAKOUT BOX INJECTOR TERMINAL IDENTIFICATION Injector Circuit Breakout Box Terminal No. (2.0L) Breakout Box Terminal No. (3.0L) INJ1F 70 75 INJ2F 96 101 INJ3F 20 74 INJ4F 95 100 INJ5F N/A 73 INJ6F N/A 99
7. Check Resistance Of Fuel Injector Harness Disconnect harness connector at suspected fuel injector. Measure resistance of VPWR circuit between breakout box terminal No. 71 or 97 and fuel injector harness connector. Measure resistance of INJ circuit between appropriate breakout box terminal and fuel injector harness connector. See «BREAKOUT BOX INJECTOR TERMINAL IDENTIFICATION»(ref-150940-S28116256382003011500000) table. If each resistance reading is less than 5 ohms, go to next step. If each resistance reading is not as specified, go to step 9.
8. Check Fuel Injector Harness Circuit For Short To Power Or Ground Measure resistance between breakout box terminal No. 71 (VPWR) and suspect fuel injector SIG circuit terminal(s). Measure resistance between breakout box terminal No. 103 (PWR GND) and suspect fuel injector SIG circuit breakout box terminal(s). See «BREAKOUT BOX INJECTOR TERMINAL IDENTIFICATION»(ref-150940-S28116256382003011500000) table. If each resistance reading is more than 10,000 ohms, go to next step. If each resistance reading is not as specified, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 20.
9. Inspect Fuel Injector Operation Remove fuel injector from suspect cylinder. Swap suspect fuel injector with a fuel injector from another cylinder. Start engine. If misfire DTC does not move to cylinder with suspect fuel injector, go to next step. If misfire DTC moves to cylinder with suspect injector, replace fuel injector. After repair, go to step 20.
10. Check Vacuum System Inspect all vacuum lines for damage, such as pinched lines, cracks, proper routing and assembly. If vehicle vacuum system is okay, go to next step. If vacuum system is not okay, repair as necessary. After repair, go to step 20. CAUTION: Remove front under cover if necessary to observe crankshaft pulley.
11. Check Damper & Pulley Assembly Observe crankshaft pulley for wobble. Examine pulse ring fastened to harmonic damper. If no problem is found, go to next step. If crankshaft pulley wobbles or pulse ring is loose or damaged, replace damper or pulse ring. Disconnect battery for 5 minutes to allow PCM to learn new data. After repair, go to step 20. NOTE: Misfire Monitor can be influenced by Evaporative Emission (EVAP) system. Next five test steps will diagnose EVAP system.
12. Check EVAP System Check EVAP canister for fuel saturation. If there is an excess amount of liquid fuel present in EVAP canister, replace EVAP canister. After repair, go to step 20. If an excess amount of liquid fuel is not present, check fuel tank vent system. Go to next step.
13. Pressure Test Evaporative Emission System Perform «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If EVAP system is holding pressure, go to next step. If EVAP system is leaking, repair as necessary. After repair, go to next step.
14. Check Vacuum In EVAP System Check for blockage/restrictions or cut hoses between engine vacuum port and EVAP canister. Check for blockage in fuel tank vent system. If no fault is indicated, go to next step. If fault is indicated, replace damaged vacuum hoses or remove blockage/restrictions. After repair, go to step 20.
15. Check For EVAP Canister Purge Valve Housing Leaks Verify EVAP canister purge valve harness connector is connected. Install hand vacuum pump to fuel vapor port on EVAP canister purge valve. Apply 16 in. Hg (53 kPa) of vacuum with vacuum pump. If EVAP canister purge solenoid holds vacuum at room temperature, go to next step. If EVAP canister purge solenoid does not hold vacuum, replace EVAP canister purge solenoid. After repair, go to step 20.
16. Check For Filter Contamination Or Damage On EVAP Canister Purge Valve Remove vacuum line from input port to intake manifold on EVAP canister purge solenoid (control vacuum solenoid part of valve). Install a hand held vacuum pump to open input vacuum port on EVAP canister purge solenoid. Apply 10-15 in. Hg (48-52 kPa) of vacuum to EVAP canister purge solenoid. If EVAP canister purge solenoid valve does not hold vacuum, remove vacuum pump and go to next step. If EVAP canister purge valve holds vacuum or if valve is very slow to release vacuum to atmosphere, service EVAP canister purge solenoid filter. If unable to clean filter or remove blockage, replace EVAP canister purge solenoid. After repair, go to step 20. NOTE: This step will determine if there are any base engine concerns that may have caused misfire DTC or driveability concern.
17. Check For Base Engine Concerns Perform the following tests in order to evaluate base engine integrity. Perform Engine Compression Test. Perform Valve Train Analysis. Check PCV system. Check possible leakage points. If any service is required, service as necessary. After service, go to step 20.
18. Check/Compare PID Values Turn all accessories off (A/C, heater, etc.). Turn Key On, Engine Off (KOEO). Access DPFEGR PID with scan tool and record values. Turn Key On, Engine Running (KOER). Compare KOEO and KOER PID values. Turn ignition off. If difference between PID values is within 0.15 volt, disconnect scan tool and go to next step. If difference between PID values is not within 0.15 volt, go to step 20.
19. Check CMP Sensor Output Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) between PCM harness connector and PCM. see scheme 2 Set multimeter on AC scale (monitor less than 5.0 volts). Measure voltage between breakout box terminal No. 85 (CMP) and terminals No. 51 and 103 (PWR GND) while running engine at varying RPM. If AC voltage varies more than 0.1 volt, ensure Camshaft Position (CMP) sensor is installed correctly. If CMP sensor is installed correctly, replace PCM. After repair, go to next step. If AC voltage reading does not vary as specified, replace CMP sensor. After repair, go to next step.
20. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool generic OBD-II function. Perform «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. Retrieve pending code. If same DTC is present replace PCM. After repair, go to next step. If same DTC is not present, go to next step.
21. Verify Trouble Shooting Of DTCs Completed Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Check Voltage Between Sensor & SIG RTN Verify KS is installed properly and harness connector is connected securely. Complete «COMPREHENSIVE COMPONENT MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S10090757572002112700000). Turn ignition on, engine off. Access KSI PID. If KSI PID reading is less than 0.5 volt, go to next step. If KSI PID is more than 0.5 volt, go to step 6.
3. Check KS Resistance Disconnect KS harness connector. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance between breakout box terminal No. 87 (2.0L) or terminal No. 32 (3.0L) and breakout box terminal No. 57. If resistance reading is more than 5.35 megohms, go to next step. If resistance reading is less than 4.39 megohms, go to step 5. If resistance reading is 4.39-5.35 megohms, go to step 7.
4. Check For Open Of KS(+) Circuit Measure the resistance of KS(+) circuit (Yellow/Red wire) between breakout box terminal No. 57 and KS harness connector. If resistance reading is less than 5.0 ohms, replace KS. After repair, go to step 8. If resistance reading is more than 5.0 ohms, repair open in Yellow/Red wire between KS and PCM 104-pin harness connector terminal No. 57. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
5. Check KS Circuits For Short To Ground In Harness Measure resistance of KS(+) circuit (Yellow/Red wire) between breakout box terminal No. 57 and KS harness connector. Measure the resistance of KS(-) circuit (Dark Green/Violet wire) between ground and breakout box terminal No. 87 (2.0L) or terminal No. 32 (3.0L). If resistance reading is more than 10,000 ohms, go to next step. If resistance reading is less than 10,000 ohms, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
6. Check KS(+) Circuit For Short To Power In Harness Connect PCM to breakout box 104-pin harness connector. Turn ignition on, engine off. Measure voltage of KS(+) circuit (Yellow/Red wire) between breakout box terminal No. 57 and negative battery terminal. If voltage reading for KS(+) was less than one volt, replace PCM. After repair, go to step 8. If voltage reading for KS(+) was more than one volt, repair short in Yellow/red wire between PCM 104-pin harness connector terminal No. 57 and KS harness connector. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
7. Check PCM For Short To Ground Reconnect PCM 104-pin harness connector to PCM. Measure resistance between KS(+) and KS(-) circuits at KS harness connector. See «WIRING DIAGRAMS»(ref-134975) article. If resistance reading is more than 10,000 ohms, replace KS. After repair, go to next step. If resistance reading is less than 10,000 ohms, replace PCM. After repair, go to next step.
8. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If PCM Quick Test was performed and engine starts, go to next step. If engine does not start, DTC P0340 is not the cause of NO START condition. Refer to «NO START»(ref-150940-S40223251252002120300000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
2. Clear & Attempt To Re-Generate DTC P0340 Clear DTCs using PCM Reset Procedure. See «CLEARING CODES»(ref-150940-S31080003522002112700000) under SELF-DIAGNOSTIC SYSTEM. Start engine. Increase engine speed to more than 1500 RPM for 10 seconds. Repeat two times. Turn ignition off. Retrieve Continuous Memory DTCs. If DTC P0340 is present, go to next step. If DTC P0340 is not present, problem is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
3. Check For Open CMP Circuit Between PCM & CMP Sensor Disconnect PCM 104-pin harness connector and CMP sensor harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of CMP circuit between breakout box terminal No. 85 and CMP sensor harness connector terminal (Dark Blue/Orange wire). Measure resistance of SIG RTN circuit between breakout box terminal No. 23 (2.0L) or terminal No. 3 (3.0L) and CMP sensor harness connector terminal (Brown/Light Green wire). If resistance readings are less than 5 ohms, go to next step. If resistance readings are not as specified, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
4. Check CMP For Short To Power Reconnect CMP sensor harness connector. Turn ignition on, engine off. Measure voltage between breakout box terminal No. 85 (CMP) and terminals No. 51 and 103 (PWR GND). Turn ignition off. If voltage reading is less than one volt, go to next step. If voltage reading was more than one volt, repair short to power in Dark Blue/Orange wire between PCM 104-pin harness connector terminal No. 85 and CMP sensor harness connector. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
5. Check CMP For Short To GND Disconnect CMP sensor harness connector. Measure resistance between breakout box terminal No. 85 (CMP) and terminal No. 23 (2.0L) or terminal No. 3 (3.0L) (SIG RTN). If resistance reading is more than 10,000 ohms, go to next step. If resistance reading is less than 10,000 ohms, repair short in Dark Blue/Orange wire between PCM 104-pin harness connector and CMP sensor harness connector. After repair, go to step 8.
6. Check For Shorts In PCM Connect PCM to breakout box 104-pin harness connector. Disconnect CMP sensor harness connector. Measure resistance between CMP (Dark Blue/Orange wire) and SIG RTN (Brown/Light Green wire) terminals at CMP sensor harness connector. If resistance reading is more than 500 ohms, go to next step. If resistance reading is 500 ohms or less, replace PCM. After repair, go to step 8.
7. Check CMP Sensor Output Reconnect CMP sensor harness connector. Set multimeter to AC scale (to monitor less than 5.0 volts). Measure voltage between breakout box terminals No. 85 (CMP) and No. 103 (PWR GND) while running engine at varying RPM. If AC voltage varies more than 0.1 volt, replace PCM. After repair, go to next step. If AC voltage does not vary more than 0.1 volt, replace CMP sensor. After repair, go to next step.
8. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Visual Inspection Visually inspect engine compartment to ensure all vacuum hoses and spark plug wires are properly routed and securely connected. Check all wiring harnesses and connectors for damaged, burned or overheated insulation and loose or broken conditions. Ensure battery is fully charged. All accessories must be off during diagnosis. If a problem is indicated, repair as necessary NOTE: In order for diagnostic procedures to provide accurate results, it is essential that the calibration of the engine analyzer be maintained. Refer to equipment manual for procedure to calibrate engine analyzer. If equipment manual is not available, an estimate of the calibration can be made by connecting a Spark Tester (303-D037) to a properly operating ignition system and measuring the firing voltage of spark tester only. The spark tester firing voltage should be approximately 28KV.
3. Connect Engine Analyzer Obtain Engine Analyzer (010-01060) or equivalent to diagnose concerns in secondary side of ignition system. After engine analyzer is connected to vehicle, go to next step.
4. Check For Ignition Pattern Observe pattern on scope while cranking engine. (Scheme 43) If ignition pattern is not flat, go to next step. If ignition pattern is flat which indicates no spark on all cylinders, check condition of No. 19 STARTER fuse (40-amp) in under-hood battery junction box. If fuse is okay, repair open circuit. If fuse/fuse link is burned, check IGN START/RUN circuit for short to ground. See «WIRING DIAGRAMS»(ref-134975) article. Repair as necessary. After repair, go to step 12. NOTE: Spark plugs are fired up to four strikes per firing. Multi-strike operating mode is dependent on PCM calibration and is limited to less than 2000 RPM. Above 2000 RPM, spark plugs are fired once per firing.
5. Check For Normal Ignition Pattern Start engine. Check spark plug firing voltage average and evenness of patterns. (Scheme 44) If patterns are even and average value of spark plug firing voltage is 20KV or more with evenness of spark plug firing voltage of 8KV or less, proceed as follows: If directed here from TROUBLE SHOOTING - NO CODES article, return to «SYMPTOM DIAGNOSIS»(ref-134968-S36579230062002022100000) in TROUBLE SHOOTING - NO CODES article. If directed here from step 5) of IGNITION SCOPE TEST under «SYSTEM TESTS»(ref-150940-S42556424782002112700000) return to step 6. All others, go to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000). If ignition pattern values are not normal as specified, go to next step.
6. Check Pattern On Scope Observe pattern on scope and look for anything unusual. (Scheme 45)- (Scheme 49) for unusual signal patterns. If ignition pattern appears normal, go to next step. If ignition pattern does not appear normal, inspect spark plug wires (if applicable). Measure resistance of spark plug wires. Replace spark plug wires if resistance reading is more than 7000 ohms per foot. If okay, go to step 10.
7. DTC P0301-P0310: Misfire On Cylinders 1-6 If any DTCs P0301-P0310 are present, go to next step. If DTCs P0301-P0310 are not present, go to step 9.
8. Check For Spark At Cylinder(s) Indicated By DTC(s) Disable Inertia Fuel Shutoff (IFS) switch. Connect spark tester and check for spark at suspect cylinder while cranking engine. If a Bluish-White spark is present, go to step 10. If a Bluish-White spark is not present, check spark plugs at cylinder with miss. Measure resistance of spark plugs. Replace spark plugs if resistance reading is less than 2000 ohms or more than 20,000 ohms. After repair, go to step 12.
9. Check For Spark At All Cylinders Disable Inertia Fuel Shutoff (IFS) switch. Using spark tester check for spark at each cylinder while cranking engine. If a Bluish-White spark is consistent between all cylinders, go to next step. If a Bluish-White spark is not present between all cylinders, measure resistance of spark plugs. Replace spark plugs if resistance reading is less than 2000 ohms or more than 20,000 ohms. After repair, go to step 12.
10. Check Spark Plugs Remove and check plugs for damage, wear, carbon deposits and proper plug gap. If spark plugs are okay, go to next step. If spark plugs are not okay, adjust gap or replace spark plugs. After repair, go to step 12.
11. Check Spark Plug Resistance Measure spark plug resistance. If resistance reading is less than 2000 ohms or more than 20,000 ohms, replace spark plugs and go to next step. If resistance reading is 2000-20,000 ohms, proceed as follows: If directed here from TROUBLE SHOOTING - NO CODES article, return to «SYMPTOM DIAGNOSIS»(ref-134968-S36579230062002022100000) in TROUBLE SHOOTING - NO CODES article. If directed here from step 5) of IGNITION SCOPE TEST under «SYSTEM TESTS»(ref-150940-S42556424782002112700000) return to step 6. All others, go to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
12. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. See «CLEARING CODES»(ref-150940-S31080003522002112700000) under SELF DIAGNOSTICS. Perform Misfire Monitor Drive Cycle. See «MONITOR REPAIR VERIFICATION DRIVE CYCLES»(ref-150940-S24809892142002112700000) under DRIVE CYCLE PROCEDURES. Retrieve pending code. If same DTC is present, replace PCM. After repair, go to next step. If same DTC is not present, go to next step.
13. Verify Trouble Shooting Of DTCs Completed Perform PCM Quick Test. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step. NOTE: If DTC P1405 is in continuous memory, diagnose that first.
2. Check For EGR Flow At Idle With EGR Vacuum Hose Disconnected Disconnect vacuum hose at EGR valve and plug hose. see scheme 18 Perform Key ON, Engine Running (KOER) Self-Test. If able to run KOER self-test, go to next step. If KOER DTC P0402 output or unable to run KOER self-test due to engine stall or no start, possible EGR flow at idle. Check pressure hoses first for pinching and icing. If okay, remove and inspect EGR valve and EGR tube for signs of contamination, unusual wear, carbon deposits, binding or damage. Repair as necessary. After repair, go to next step.
3. Check For EGR Flow At Idle With EGR Vacuum Hose Connected Reconnect EGR vacuum hose. Perform KOER self-test. Turn ignition off. If able to run KOER self-test, fault is intermittent. Inspect pressure hoses for pinching or icing. Repair as necessary. After repair, go to step 11. If KOER DTC P0402 output or unable to run KOER self-test due to engine stall or no start, possible EGR flow at idle. Go to next step. NOTE: A pinched or plugged EGR vacuum hose can trap vacuum between EGR vacuum regulator solenoid and EGR valve not allowing EGR valve to close.
4. Check EGR System Vacuum Hoses For Integrity & Connection Trace each vacuum hose from EGR vacuum regulator solenoid and verify that each hose is connected properly. Refer to «VACUUM DIAGRAMS»(ref-12158) article. Ensure EGR valve vacuum hose is not pinched or plugged and is routed properly. If vacuum hoses are okay, reconnect vacuum hoses and go to next step. If vacuum hoses are not okay, repair as necessary. After repair, go to step 14.
5. Check DPFEGR Sensor Output By Applying Vacuum With Hand Pump Disconnect pressure hoses at DPFEGR sensor. Connect a hand vacuum pump to downstream connection at sensor (intake manifold side of sensor or smaller diameter pickup tube). Turn ignition on, engine off. Access DPFEGR PID with scan tool and record PID value. Apply 8-9 in. Hg (27-30 kPa) vacuum to the DPFE sensor and hold for a few seconds. Quickly release vacuum. DPFEGR PID voltage reading must be 0.2-1.3 volts with ignition on and no vacuum applied. DPFEGR PID voltage reading must increase to more than 4.0 volts with vacuum applied. DPFEGR PID voltage reading must drop to less than 1.5 volts in less than 3 seconds when vacuum is released. If DPFEGR PID voltage reading did not indicate a fault in DPFEGR sensor, go to next step. If DPFEGR PID voltage reading indicated a fault in DPFEGR sensor, replace DPFEGR sensor. After repair, go to step 15.
6. Check For EGR Flow At Idle With EGRVR Solenoid Connector Off Disconnect vacuum hose at EGR valve and connect hose to vacuum gauge. Start engine and bring to an idle. While monitoring vacuum gauge, disconnect EGRVR solenoid harness connector. EGR valve requires vacuum more than 1.6 in. Hg (5.4 kPa) to begin to open. If vacuum reading remains more than 1.6 in. Hg (5.4 kPa) after EGRVR solenoid harness connector is disconnected, this would indicate a mechanical fault in EGRVR solenoid. Turn ignition off. If EGR vacuum remained more than 1.6 in. Hg (5.4 kPa) at idle even after EGRVR solenoid harness connector was disconnected, go to next step. If EGR vacuum did not remain more than 1.6 in. Hg (5.4 kPa) at idle even after EGRVR solenoid harness connector was disconnected, go to step 8. NOTE: A plugged EGR vacuum regulator solenoid vent will not allow EGR vacuum to vent to atmosphere.
7. Inspect EGRVR Solenoid Vent For Plugging Disconnect EGRVR solenoid vacuum hoses. Remove EGRVR solenoid vent cap (if removable). Remove filter and inspect for blockage or icing in some cases. With EGR vacuum supply port plugged, apply 10-15 in. Hg (34-51 kPa) of vacuum directly to EGRVR solenoid vacuum source port with a hand vacuum pump. If vacuum holds or is slow to release to atmosphere, EGRVR solenoid vent could be plugged or restricted. If EGRVR solenoid vent or vent filter is not plugged or restricted, replace EGRVR solenoid. After repair, go to step 15. If EGRVR solenoid vent or vent filter is plugged or restricted, repair EGRVR solenoid as necessary. If unable to repair, replace EGRVR solenoid. After repair, go to step 15.
8. Measure Resistance Across EGRVR Solenoid Disconnect EGRVR solenoid. Measure resistance across EGRVR solenoid terminals. If EGRVR solenoid resistance reading is 26-40 ohms, go to next step. If EGRVR solenoid resistance reading is not as specified, replace EGRVR solenoid. After repair, go to step 15.
9. Check EGRVR Circuit For Short To Ground In Harness Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance between breakout box terminal No. 79 (2.0L) or terminal No. 47 (3.0L) (EGRVR) and breakout box terminals No. 51 and 103 (PWR GND). If resistance reading is more than 10,000 ohms, go to next step. If resistance reading is less than 10,000 ohms, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 15.
10. Check EGRVR Circuit For Short To VREF Measure resistance between breakout box terminal No. 79 (2.0L) or terminal No. 47 (3.0L) (EGRVR) and terminal No. 90 (VREF). If resistance reading is more than 10,000 ohms, replace PCM. After repair, go to step 15. If resistance reading is less than 10,000 ohms, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 15.
11. Check DPFEGR Sensor Output By Applying Vacuum With Hand Pump Disconnect pressure hoses at DPFEGR sensor. Connect a hand vacuum pump to downstream connection at sensor (intake manifold side of sensor or smaller diameter pickup tube). Turn ignition on, engine off. Access DPFEGR PID with scan tool and record PID value. Apply 8-9 in. Hg (27-30 kPa) vacuum to DPFEGR sensor and hold for a few seconds. Quickly release vacuum. DPFEGR PID voltage reading must be 0.2-1.3 volts with ignition on and no vacuum applied. DPFEGR PID voltage reading must increase to more than 4.0 volts with vacuum applied. DPFEGR PID voltage reading must drop to less than 1.5 volts in less than 3 seconds when vacuum is released. Turn ignition off. If DPFEGR PID voltage reading indicated a fault in the DPFEGR sensor, replace DPFEGR sensor. After repair, go to step 15. If DPFEGR PID voltage reading did not indicate a fault in the DPFEGR sensor, reconnect sensor and go to next step.
12. Check DPFEGR Sensor Voltage While Exercising EGR Valve Turn ignition on, engine off. View DPFEGR PID with scan tool and record PID voltage reading. Typical DPFEGR sensor voltage with no EGR flow is 0.2-1.3 volts. Disconnect and plug vacuum hose at EGR valve. Connect a hand vacuum pump to EGR valve. Start engine and bring to idle. Observe DPFEGR PID voltage reading at idle and compare to KOEO voltage reading. A higher voltage at idle could be due to a non-seating EGR valve. Apply just enough vacuum to EGR valve to open it 2-3 in. Hg (7-10 kPa) without stalling engine and release vacuum. Repeat several times while observing DPFEGR PID on scan tool. DPFEGR PID voltage reading should increase as valve begins to open and return to initial voltage reading as vacuum is released. A slow to return voltage reading could be an indication of a binding or slow-closing EGR valve. Turn ignition off. If DPFEGR PID voltage reading did not indicate an open, binding or slow-closing EGR valve, go to next step. If DPFEGR PID voltage reading indicated an open, binding or slow-closing EGR valve, inspect EGR valve for signs of contamination, unusual wear, carbon deposits, binding or damage. Repair as necessary. After repair, go to step 15. NOTE: An intermittent short to GND in the EGR vacuum regulator circuit will cause the vacuum applied to the EGR valve to be higher than normal while short is present.
13. Monitor EGR Valve Vacuum While Wiggling EGRVR Circuit Vacuum available at EGR valve at idle is normally below one in. Hg (3.4 kPa) and it takes about 1.6 in. Hg (5.4 kPa) for valve to begin to open. Disconnect vacuum hose at EGR valve from hand vacuum pump and connect hose to a vacuum gauge. Start engine. Observe vacuum gauge for an indication of a fault while performing the following: Lightly tap on EGRVR solenoid. Wiggle EGRVR solenoid connector and vehicle harness between solenoid and PCM. A fault is indicated by a sudden jump in vacuum reading. Turn ignition off. If a fault was indicated, isolate fault and repair as necessary. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 15. If no fault was indicated, reconnect vacuum hose and go to next step.
14. Inspect EGRVR Solenoid & Vacuum Hoses For Potential Plugging Remove EGRVR solenoid vent filter and inspect for contamination and excessive water absorption. In cold climate, excessive water in filter could freeze and plug EGRVR solenoid vent. Inspect EGR vacuum hose for possible blockage and pinching. If EGRVR solenoid vent or filter was contaminated or vacuum hose plugged, repair EGRVR solenoid or vacuum hose as necessary. After repair, go to next step. If EGRVR solenoid vent or filter were not contaminated or vacuum hose plugged, unable to duplicate or identify fault at this time. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
15. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If entering this test from Symptom Trouble Shooting, go to next step. IF QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and any other DTCs are present, go to applicable procedure for other DTCs first. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If only DTC P0420 and/or P0430 are present, go to next step. NOTE: If electrical connections of rear HO2S are interchanged/crossed, Catalyst Efficiency Monitor Test will fail.
2. Check Rear HO2S Wiring & PCM Connections Inspect wiring of rear HO2S for proper routing and connection. Disconnect PCM 104-pin harness connector, inspect for damaged or pushed out pins, corrosion and loose wires. If any wiring or connection concerns are present, repair as necessary. If faulty terminals at PCM are present, replace PCM. After repair, go to step 10 . If no faults are present related to DTCs, go to next step. WARNING: Fuel system will remain pressurized when engine is not running. To prevent injury or fire, use caution when working on fuel system. NOTE: Fuel pressures above specification can produce abnormally rich air/fuel mixture. Rich air/fuel mixture can cause higher than normal catalyst operating temperatures.
3. Check Fuel Pressure Install fuel pressure gauge. Start and run engine at idle. Record fuel pressure. Increase engine speed to 2500 RPM and maintain for one minute. Record fuel pressure. If fuel pressure is 55-70 psi (380-482 kPa), go to next step. If fuel pressure is not as specified, refer to «FUEL DELIVERY SYSTEM»(ref-150940-S38917645432002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000) .
4. Check For Obvious Leak Sources In Exhaust System If a catalyst is in series with a leaking exhaust system, it can fail Catalyst Efficiency Monitor test. Turn ignition off. Inspect following for leaks, cracks, loose connections or punctures: Exhaust manifold. Front exhaust pipe. Rear exhaust pipe. Muffler/tailpipe assembly. If components are free of cracks and punctures, etc., go to next step. If components are not free of cracks or punctures, repair source of fault as necessary. After repair, go to step 10 .
5. Check For Obvious Restrictions In The Exhaust System Inspect following for dents, areas of collapsed material and unusual bending: Front exhaust pipe. Rear exhaust pipe. Muffler/tailpipe assembly. If components are free of dents and areas of collapsed material or unusual bending, etc., go to next step. If components are not free of dents and areas of collapsed material or unusual bending, etc., repair restricted components as necessary. After repair, go to step 10 . NOTE: Vacuum gauge reading may be normal when engine is first started and idled. However, excessive restriction in exhaust system will cause vacuum gauge needle to drop to a low point even while engine is idled.
6. Check Manifold Vacuum For Indication Of Excessive Exhaust System Restriction Attach vacuum gauge to intake manifold vacuum source. Monitor RPM with scan tool or tachometer. Observe vacuum gauge needle while performing following: Start engine and gradually increase engine speed to 2000 RPM with transaxle in neutral. Decrease engine speed to base idle RPM. Turn ignition off. If manifold vacuum rose above 16 in. Hg (54 kPa) with engine at 2000 RPM, go to next step. If manifold vacuum did not rise as specified, go to step 8 .
7. Check Manifold Vacuum For Indication Of Moderate Exhaust System Restriction Start engine. Increase engine speed gradually from base idle RPM to 2000 RPM with transaxle in neutral. Observe rate of speed vacuum gauge needle rises, while maintaining increased engine RPM. On a non-restricted exhaust system, vacuum gauge needle will rise quickly to above 16 in. Hg (54 kPa) (normal range) as increased RPM is maintained. On a restricted exhaust system, vacuum gauge needle will rise slowly to normal range as increased RPM is maintained. Decrease engine speed to base idle RPM. Turn ignition off. If rate of speed that vacuum gauge needle rose back to normal range was much slower than that of a non-restricted system, go to next step. If rate of speed that vacuum gauge needle rose back to normal range was same as that of a non-restricted system, no fault is present. If here because of DTCs P0420 or P0430, catalytic converter is chemically inactive. Replace catalytic converter. After repair, go to step 10 . NOTE: In following step, do not use a wire or lamp to check ports. Restriction may be small enough for both to pass through, but large enough to cause excessive back-pressure at high engine RPM.
8. Check Manifold Vacuum With Exhaust Manifold Disconnected For Indication Of A Restriction An intake manifold gasket leak can also cause vacuum gauge needle to remain well below normal range. Turn ignition off. Disconnect exhaust system immediately after exhaust manifold. Repeat vacuum measurement performed in step 7) . If vacuum needle quickly rose above 16 in. Hg (54 kPa) with engine speed at 2000 RPM, exhaust restriction is down stream of exhaust manifold. Reconnect exhaust system. Go to next step. If vacuum needle did not rise quickly above 16 in. Hg (54 kPa) with engine speed at 2000 RPM, a restriction is present in exhaust manifold. Remove vacuum gauge and tachometer. Inspect exhaust manifold for casting flash/restrictions by dropping length of chain into it. Replace exhaust manifold if unable to remove casting flash/restriction. After repair, go to step 10 .
9. Check Manifold Vacuum With Muffler/Tailpipe Assembly Disconnected For Indication Of A Restriction Turn ignition off. Disconnect muffler/tailpipe assembly located after catalytic converter. Repeat vacuum measurement performed in step 7). If vacuum needle quickly rose above 16 in. Hg (54 kPa) with engine speed at 2000 RPM, restriction is in muffler and tailpipe. Replace muffler and tail pipe. After repair, go to next step. If vacuum needle did not rise quickly above 16 in. Hg (54 kPa) with engine speed at 2000 RPM, restriction is in catalytic converter. Remove vacuum gauge and tachometer. Replace catalytic converter. Ensure converter debris did not enter muffler. After repair, go to next step.
10. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool generic OBD-II function. Perform Catalyst Monitor Repair Verification Drive Cycle. Refer to «MONITOR REPAIR VERIFICATION DRIVE CYCLES»(ref-150940-S24809892142002112700000) under DRIVE CYCLE PROCEDURES. Retrieve pending code. If same DTC is present, replace PCM. After repair, go to next step. If same DTC is not set, go to next step.
11. Verify Trouble Shooting Of DTCs Completed Perform PCM Quick Test. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Visually Inspect Components For Small Leaks Check for presence of fuel filler cap. DO NOT tighten or check for correct installation at this time. Verify that Canister Vent (CV) solenoid is properly seated on EVAP canister. Visually inspect for cut or loose connections to fuel vapor hoses/tubes in following locations: EVAP canister to EVAP vapor management valve. EVAP canister to evaporative emission valve assembly. Evaporative emission valve assembly to fuel tank (if applicable). Check for fuel filler pipe damage. If concern with a hose, tube, connection, or valve is visually evident, repair or install NEW component as necessary. After repair, go to step 10 . If no problems are found, go to next step.
3. Check For Small System Leaks From EVAP Test Port Connect EVAP System Leak Tester to EVAP test port. Perform EVAP System Leak Test. Refer to «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If EVAP system passed leak test, go to next step. If EVAP system failed leak test, go to step 5 .
4. Check For Small Leaks At Fuel Filler Cap & EVAP Test Port Connect EVAP System Leak Tester to fuel filler pipe. Turn ignition on, engine off. Close EVAP Canister Vent (CV) solenoid using EVAPCV PID. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND modes. Select OUTPUT TEST mode. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). Using ultrasonic leak detector, check for leaks around fuel filler cap and EVAP test port. If a leak is detected, repair or replace component as necessary. After repair, go to step 9 . If a leak is not detected, remove leak tester. Install fuel filler cap and go to step 11 .
5. Visually Inspect Fuel Filler Cap Visually inspect fuel filler cap for damage. If fuel filler cap is damaged, install NEW filler cap. After repair, go to step 11 . If fuel filler cap is okay, go to next step.
6. Check For Small Leak With Tester Set At FILL Position Turn ignition on, engine off. Close EVAP Canister Vent (CV) solenoid using EVAPCV PID from OUTPUT TEST mode on scan tool. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). If pressure holds between 13.80 and 14.20 in. H 2 O (3.43 and 3.53 kPa), go to next step. If pressure does not hold as specified, go to step 8 .
7. Check For Leaks In Complete EVAP System Verify EVAP Canister Vent (CV) solenoid is closed. Verify system is pressurized to 14 in. H 2 O (3.48 kPa). Using ultrasonic leak detector, check following EVAP system locations: EVAP return tube to EVAP vapor management valve. EVAP vapor management valve to EVAP CV solenoid assembly. EVAP CV solenoid assembly to fuel tank. Fuel filler cap and fuel filler pipe. If a leak is detected, repair or install NEW component as necessary. After repair, go to step 10 . If a leak is not detected, Discontinue pressurizing system. Go to next step.
8. Check For Small Leak From EVAP Return Tube To EVAP Canister Disconnect fuel tank vapor tube at fuel vapor tee and plug opening in tee. Turn ignition on, engine off. Close EVAP Canister Vent (CV) solenoid using EVAPCV PID from OUTPUT TEST mode on scan tool. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). Using ultrasonic leak detector, check EVAP system from intake manifold to EVAP CV solenoid. If a leak is detected, repair or install NEW component as necessary. After repair, go to step 10 . If a leak is not detected, open EVAP CV solenoid and go to next step.
9. Check For Small Leak Between Fuel Tank Vapor Tube & Fuel Tank Filler Pipe Transfer plug from fuel vapor tee to fuel tank vapor tube. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). Using ultrasonic leak detector, check fuel tank vapor tube to fuel tank for leaks. Check Fuel Tank Pressure (FTP) sensor, fuel tank vapor tube and fuel filler pipe. If a leak is detected
10. EVAP System Leak Test Connect all disconnected connectors and hoses. Perform EVAP System Leak Test. Refer to «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If test result is okay, go to step 12 . If test result is not okay, locate leak and repair. After repair, repeat EVAP System Leak Test.
11. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool generic OBD-II function. Perform Catalyst Monitor Repair Verification Drive Cycle. Refer to «MONITOR REPAIR VERIFICATION DRIVE CYCLES»(ref-150940-S24809892142002112700000) under DRIVE CYCLE PROCEDURES. Retrieve pending code. If same DTC is present, replace PCM. After repair, go to next step. If same DTC is not set, go to next step.
12. Verify Trouble Shooting Of DTCs Completed Perform PCM Quick Test. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

Note. EVAP canister purge valve may also be referred to as EVAP vapor management valve.

Scheme 42

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, fault that produced Continuous Memory DTC P0443 (without KOEO or KOER P0443) can be intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000). If fault is not intermittent, replace PCM. If KOEO or KOER P0443 is also present, go to next step.
2. Check For VPWR To EVAP Canister Purge Solenoid Turn ignition off. Disconnect EVAP Canister Purge Valve (EVAPCPV) harness connector. Turn ignition on, engine off. Measure voltage between ground and VPWR (Red wire) at EVAPCPV harness connector. (Scheme 42) If voltage reading is more than 10.5 volts, go to next step. If voltage reading is not as specified, repair open in Red wire between EVAPCPV harness connector and PCM 104-pin harness connector terminal No. 71. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 7. NOTE: EVAP canister purge valve resistance reading must be taken with engine cooled down.
3. Check EVAP Canister Purge Solenoid Resistance Turn ignition off. With EVAPCPV disconnected. Measure resistance between EVAPCPV and VPWR terminals at EVAPCPV. If resistance reading is 30-38 ohms, go to next step. If resistance reading is not as specified, replace EVAPCPV. After repair, go to step 7.
4. Check Resistance Of EVAPCPV Circuit Disconnect PCM 104-pin harmess connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of EVAPCPV circuit between breakout box terminal No. 56 and EVAPCPV harness connector. If resistance reading is less than 5.0 ohms, go to next step. If resistance reading is not as specified, repair open in EVAPCPV circuit (Light Green/Black wire) between PCM 104-pin harness connector terminal No. 56 and EVAPCPV harness connector. After repair, go to step 7.
5. Check EVAP Canister Purge Solenoid Circuit For Short To PWR GND Disconnect scan tool from DLC. Measure resistance between breakout box terminal No. 56 (EVAPCPV) and terminal No. 103 (PWR GND). Is resistance reading is more than 10,000 ohms, go to next step. If resistance reading is less than 10,000 ohms, repair short between EVAPCPV (Light Green/Black wire) and PWR GND (Black wire). See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 7.
6. Check EVAPCPV Circuit For Short To VPWR Turn ignition on, engine off. Measure voltage between breakout box terminal No. 56 (EVAPCPV) and terminal No. 103 (PWR GND). If voltage reading is more than 10.5 volts, repair short to power between EVAPCPV (Light Green/Black wire) and VPWR (Red wire). After repair, go to next step. If voltage reading is not as specified, replace PCM. After repair, go to next step.
7. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Perform PCM Quick Test. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

If QUICK TEST was not performed, go to QUICK TEST under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and any other DTC is present, go to appropriate trouble shooting for that DTC first. If only DTC P0451 and/or P0461 are present, refer to INTERMITTENT testing under SYSTEM TESTS .

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. DTC P0453: Verify FTP Voltage Turn ignition on, engine off. Access FTP V PID with scan tool. If FTP V PID voltage reading is more than 4.5 volts, go to next step. If FTP V PID voltage reading is not more than 4.5 volts, problem is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
3. Check FTP At FTP Sensor For Short To Power Turn ignition off. Disconnect FTP sensor 3-pin harness connector. Turn ignition on, engine off. Measure voltage between ground and FTP circuit (Red/Pink wire) at FTP sensor 3-pin harness connector. see scheme 20 If voltage reading is more than 10.5 volts, go to next step. If voltage reading is not more than 10.5 volts, go to step 5.
4. Check FTP Circuit For Short To VPWR Turn ignition off. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Turn ignition on, engine off. Measure voltage between breakout box terminal No. 62 (FTP) and terminal No. 103 (PWR GND). If voltage reading is more than 10.5 volts, repair short to VPWR in Red/Pink wire between FTP sensor 3-pin harness connector and PCM 104-pin harness connector terminal No. 62. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 11. If voltage reading is not more than 10.5 volts, FTP circuit is shorted inside PCM. Replace PCM. After repair, go to step 11. NOTE: If a scan tool communication concern exists during next step, remove fused jumper wire immediately and go to step 10.
5. Induce Opposite FTP Signal Turn ignition off. Attach a fused jumper wire between FTP sensor SIG RTN circuit (Orange wire) and FTP circuit (Red/Pink wire) at FTP sensor 3-pin harness connector. Turn ignition on, engine off. Access FTP V PID with scan tool. If FTP V PID voltage reading is less than 0.10 volt, remove fused jumper wire and go to next step. If FTP V PID voltage reading is not as specified, go to step 8.
6. Verify That VREF Is In Range Measure voltage between VREF (Brown/White wire) and SIG RTN (Orange wire) at FTP sensor 3-pin harness connector. If VREF voltage reading is 4-6 volts, go to next step. If VREF voltage reading is not as specified, refer to «VEHICLE REFERENCE VOLTAGE»(ref-150940-S23619745912002112700000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
7. Check FTP For Short To VREF In Sensor Or Harness Turn ignition off. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance between breakout box terminals No. 62 (FTP) and No. 90 (VREF). If resistance reading is more than 10,000 ohms, replace FTP sensor. After repair, go to step 11. If resistance reading is not as specified, repair short between FTP SIG circuit (Orange wire) and VREF circuit (Brown/White wire) or PWR GND circuit (Black wire). See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 11.
8. Check Resistance Of FTP Circuit Turn ignition off. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of FTP circuit (Red/Pink wire) between breakout box terminal No. 62 and FTP sensor 3-pin harness connector. see scheme 20 If resistance reading is less than 5.0 ohms, go to next step. If resistance reading is not as specified, repair open in Red/Pink wire between PCM 104-pin harness connector terminal No. 62 and FTP sensor 3-pin harness connector. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 11.
9. Check Resistance Of SIG RTN Circuit Measure resistance of SIG RTN circuit (Orange wire) between breakout box terminal No. 91 and FTP sensor 3-pin harness connector. If resistance reading is less than 5.0 ohms, go to next step. If resistance reading is not as specified, repair open in Orange wire between PCM 104-pin harness connector terminal No. 91 and FTP sensor 3-pin harness connector.
10. Check FTP For Short To VREF In PCM Or Harness Measure resistance between breakout box terminals No. 62 (FTP) and No. 90 (VREF). If resistance reading is more than 10,000 ohms, replace PCM. After repair, go to next step. If resistance reading is not as specified, repair short between FTP circuit (Red/Pink wire) and VREF circuit (Brown/White wire). After repair, go to next step.
11. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and DTC P0455 is present, go to next step. If DTC P1443 is present, go to step 3 .
2. Visually Check For Large EVAP System Leak Check for presence of fuel filler cap. DO NOT tighten or check for correct installation at this time. Verify that both input port vacuum hose and EVAP return tube are attached to EVAP Canister Purge Valve (EVAPCPV). Verify Canister Vent (CV) solenoid is properly attached to EVAP canister. Visually inspect for disconnected or cracked fuel vapor hoses/tubes between intake manifold and following components: EVAPCPV EVAP canister Fuel vapor vent valve assembly Check for damage to fuel filler pipe and fuel tank. If concern is not visually evident, go to next step. If a concern is visually evident, repair or replace EVAP components as necessary. After repair, go to step 7 .
3. Check For EVAP System Leaks Disconnect EVAP return tube from intake manifold and plug EVAP return tube. Connect EVAP System Leak Tester to EVAP test port. Perform EVAP System Leak Test. Refer to «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If pressure reading stays above 8 in. H 2 O (1.99 kPa), go to next step. If pressure reading is not as specified, verify fuel filler cap is installed correctly. Repair or replace as necessary. After repair, go to step 7 .
4. Check For Blockage Between EVAP Canister Purge Valve & Fuel Vapor Tee Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Select OUTPUT TEST MODE. Close EVAP CV solenoid using EVAPCV PID. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). Press STOP (#4) on scan tool to open EVAP CV solenoid. If pressure drops immediately, go to next step. If pressure does not drop immediately, replace vapor line between EVAP CV and vapor tee. After repair, go to step 8 .
5. Check For Blockage Between Fuel Filler Pipe & Fuel Vapor Tee Connect the EVAP System Leak Tester to the fuel filler pipe. Close EVAP Canister Vent (CV) solenoid using EVAPCV PID from OUTPUT TEST MODE. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). Press STOP (#4) to open EVAP CV solenoid. If pressure drops immediately, go to next step. If pressure does not drop immediately, replace fuel tank vapor line(s). Repeat this step to verify repair. After repair, go to step 8 .
6. Check For Failed EVAP Canister Purge Valve Or Fuel Tank Pressure Sensor If both P0455 and P1443 present at step 1), replace EVAPCPV. After repair, go to next step. If both P0455 and P1443 were not present at step 1), replace FTP sensor. After repair, go to next step.
7. EVAP System Leak Test Connect all disconnected connectors and hoses. Perform EVAP system leak test. Refer to «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If test result is okay, go to step 9 . If test result is not okay, locate leak and repair. After repair, repeat this step.
8. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool generic OBD-II function. Perform EVAP System Monitor Drive Cycle. Refer to «EVAP RUNNING LOSS SYSTEM REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S35062712432002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. Retrieve pending code. If same DTC is present, replace PCM. After repair, go to next step. If same DTC is not present, go to next step.
9. Verify Trouble Shooting Of DTCs Completed Perform PCM Quick Test. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Check For Missing Or Leaking Fuel Filler Cap Check for missing or loose fuel filler cap. Check for possible cross-threaded fuel filler cap. If a concern is present, repair or replace as necessary. After repair, go to next step. If a concern is not present, go to step 4 .
3. EVAP System Leak Test Perform EVAP system leak test. Refer to «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If test result is okay, go to next step. If test result is not okay, go to «DTC P0455 OR P1443»(ref-150940-S23701737862002112700000) trouble shooting.
4. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool generic OBD-II function. Perform EVAP System Monitor Drive Cycle. Refer to «EVAP RUNNING LOSS SYSTEM REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S35062712432002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. Retrieve pending code. If DTC P0455 and P0457 are not present, go to next step. If DTC P0455 and P0457 are still present, go to «DTC P0455 OR P1443»(ref-150940-S23701737862002112700000) trouble shooting.
5. Verify Trouble Shooting Of DTCs Completed Perform PCM Quick Test. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete. Advise customer that it is important and necessary to tighten fuel filler cap after refueling.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and DTC P1639 is present, go to next step. For all other DTCs, go to step 3.
2. Program PCM Parameters Connect scan tool with flash cable. Turn ignition on, engine off. Select DIAGNOSTIC DATA LINK. Select PCM. Select MODULE CONFIGURATION and follow directions to access. Scroll to TIRE SIZE and press TRIGGER. Turn dial to select 720 for 235/70R16 tires or 749 for 215/70R16 tires then press TRIGGER. Scroll to AXLE RATIO and press TRIGGER. Turn dial to select 3.78 and press TRIGGER. Press START to program PCM parameters. Press CANCEL to return to first screen. If programming was successful, Clear DTCs and perform brief drive cycle of at least a quarter mile. Start and stop vehicle 2 times during cycle, turning ignition on and off. After completing drive cycle, go to step 6. If programming was unsuccessful, refer to appropriate MODULE COMMUNICATIONS NETWORK article in ACCESSORIES & EQUIPMENT. NOTE: If KAPWR is interrupted to PCM (when breakout box is installed or battery is disconnected), DTCs P0603 and P1605 can be generated on first power-up.
3. Check Battery Terminals Inspect battery cables for loose connections, corrosion. If battery terminal connections are in good condition, go to next step. If battery connections are not good, repair as necessary. After repair, go to step 6.
4. Inspect Engine Compartment For Proper Wire Routing Inspect engine compartment wiring for proximity to ignition components or wires. If wiring is too close to ignition components or wires, reroute wiring as necessary. If wire harness routing is okay, go to next step.
5. Check Keep Alive Power (KAPWR) To PCM Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure voltage between breakout box terminals No. 55 (KAPWR) and No. 103 (PWR GND). While observing multimeter, grasp engine harness and wiggle, shake or bend a small section while working from PCM to dash panel. If voltage reading indicates less than 10.5 volts at any time, repair open in KAPWR circuit (Red/Light Green wire).
6. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and brake pedal was applied during KOEO self-test, perform KOEO self-test again and avoid applying brake pedal during test. If brake pedal was not applied and released during KOER self-test, perform KOER self-test again and ensure brake pedal is applied and released. For KOEO DTC P0703 or P1703, go to step next step. For KOER DTC P0703 or P1703, go to step 3.
2. DTCS P0703 & P1703: Check Operation Of Stop lamps Apply and release brake pedal several times and observe stop lamp operation. If stop lamps operate normally, go to next step. If stop lamps are never on, go to step 4. If stop lamps are always on, go to step 6.
3. Check For PCM BPP/BOO PID Cycling Turn ignition on, engine off. Access BPP/BOO PID with scan tool. Apply and release brake pedal several times while viewing BPP/BOO PID. If BPP/BOO PID cycles ON/OFF, problem is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000). If BPP/BOO PID does not cycle ON/OFF, go to step 9. NOTE: Check the condition of the stop lamp bulbs before starting this test.
4. Check For Power To BPP Switch Disconnect BPP switch harness connector. Measure B+ input voltage between chassis ground and BPP switch harness connector (Light Green/Red wire). If voltage reading is more than 10 volts, go to next step. If voltage reading is not as specified, verify integrity of No. 24 fuse (15-amp) for B+ to BPP switch. If okay, repair open in B+ circuit (Light Green/Red wire. If No. 24 fuse (15-amp) is damaged, check B+ circuit (Light Green/Red wire), BPP circuit (Light Green wire), stop lamp PWR circuit (light Green wire) and any other associated circuits for short to ground. See «WIRING DIAGRAMS»(ref-134975) article. Repair as necessary. After repair, go to step 10.
5. Verify Integrity Of BPP Switch Connect DVOM test probes to BPP switch terminals. Apply brake pedal while monitoring resistance reading. If resistance reading is less than 5.0 ohms, repair open circuit between BPP switch and stop lamp ground. After repair, go to step 10. If resistance reading is not as specified, replace BPP switch. After repair, go to step 10.
6. Verify BPP Switch Is Not Always Closed Turn ignition off. Disconnect BPP switch harness connector. Turn ignition on, engine off. If stop lamps are still on, go to next step. If stop lamps are not on, ensure BPP switch is adjusted correctly. If BPP switch is installed correctly, replace BPP switch. After repair, go to step 10.
7. Check For Short To Power In PCM Turn ignition off. Disconnect PCM 104-pin harness connector. Turn ignition on, engine off. If stop lamps are still on, go to next step. If stop lamps are not on, replace PCM. After repair, go to step 10.
8. Check Stop Lamp Circuit For Short To Power In Harness One at a time, disconnect all modules associated with stop lamp circuit (PCM, cruise control, GEM, 4WABS and RABS). See «WIRING DIAGRAMS»(ref-134975) article. After disconnecting each module, turn ignition on and observe stop lamps. Turn ignition off. Repeat until each associated module has been disconnected or stop lamps turn off. If stop lamps turned off when any modules were disconnected, go to appropriate MODULE COMMUNICATIONS NETWORK article in ACCESSORIES & EQUIPMENT.
9. Check For BPP Circuit Cycling Turn ignition off. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure voltage between breakout box terminals No. 92 (BPP) and No. 76 (PWR GND) while applying and releasing brake pedal. If voltage reading cycles, replace PCM. After repair, go to next step. If voltage reading does not cycle, repair open in BPP circuit (Light Green wire) to PCM 104-pin harness connector terminal No. 92. After repair, go to next step.
10. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step. NOTE: During KOEO self-test, clutch pedal must be down for manual transaxle.
2. Check CPP Switch Function Turn ignition on, engine off. Access CPP PID and observe PID cycling ON/OFF with clutch pedal up, then down (M/T). If CPP PID reading changes from ON to OFF, problem is intermittent. Inspect both ends or PCM 104-pin harness connector for pushed out terminals, corrosion and loose wires. Repair as necessary. If connector is okay, replace PCM. If CPP PID reading does not change from ON to OFF, go to next step.
3. Check CPP Switch Turn ignition off. Locate CPP switch near clutch pedal. Inspect switch and bracket for damage, bent or broken conditions. Repair as necessary. Disconnect CPP harness connector and inspect for damage, pushed out or broken pins and broken wires. Repair as necessary. Measure resistance across CPP switch terminals with clutch pedal down. If resistance reading is less than 5.0 ohms, go to next step. If resistance reading is not as specified, replace CPP switch. After repair, go to step 6.
4. Check Resistance Of CPP Circuit Disconnect scan tool. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of CPP circuit between breakout box terminal No. 64 and CPP switch harness connector (Light Blue/Yellow wire). If resistance reading is less than 5.0 ohms, go to next step. If resistance reading is not as specified, replace CPP switch. After repair, go to step 6.
5. Check CPP Circuit For Short Measure resistance between breakout box terminals No. 64 (CPP) and No. 91 (SIG RTN). Measure resistance between ground and breakout box terminal No. 64 (CPP). If each resistance reading is more than 10,000 ohms, go to next step. If each resistance reading is not as specified, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to next step.
6. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step. NOTE: DTC P1000 indicates that all OBD II monitors have not yet been successfully tested to clear DTC P1000.
2. DTC P1000: Check For Other DTCs Test should be used only if DTC P1000 was received in Continuous Memory. Ignore any DTC P1000s in KOEO or KOER. If no other DTCs were received with P1000, go to next step. If any other DTCs were received with P1000, repair those DTCs first. Refer to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) .
3. Request To Clear DTC P1000 If customer has requested DTC P1000 be cleared from PCM memory, go to next step. If customer has not requested DTC P1000 be cleared from PCM memory, inform customer that if the law in this state requires additional driving in order to clear DTC P1000 from PCM memory, it must be performed before an inspection/maintenance test.
4. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are present, trouble shooting is complete.

KOER P1127 - Scan to connected. Turn ignition on, engine off. Access following PIDs

1. HTR11 (Front Bank 1).
2. HTR21 (Front Bank 2).
3. HTR12 (Rear Bank 1).
4. HTR22 (Rear Bank 2).

Turn ignition off. If all PIDs indicate ON, perform KOER self-test. If all PIDs do not indicate ON, operate engine until all PIDs indicate ON. Refer to QUICK TEST under SELF-DIAGNOSTIC SYSTEM.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Inspect HO2S Harness Connectors Visually inspect vehicle front HO2S harness connector(s) (P1128) or rear HO2S harness connector(s) (P1129) for any indication of being crossed (stretched wires, wire harnesses not mounted properly). If there are no crossed connections or wires, go to next step. If there are any crossed connections or wires, repair as necessary. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 4.
3. Verify Proper HO2S SIG PIN Location Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 For DTC P1128, disconnect both front HO2Ss from vehicle harness connectors. HO2S-11 (Front Bank 1) = breakout box terminal No. 60. HO2S-21 (Front Bank 2) = breakout box terminal No. 87. For P1129, disconnect both rear HO2Ss from vehicle harness connectors. HO2S-12 (Rear Bank 1) = breakout box terminal No. 35. HO2S-22 (Rear Bank 2) = breakout box terminal No. 60. Measure resistance of HO2S signal circuits between appropriate breakout box terminals and HO2S 4-pin harness connector. If resistance reading is more than 5.0 ohms, go to next step. If resistance reading is less than 5.0 ohms, problem is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
4. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. DTCS P1131, P1151: Upstream HO2S(s) Not Switching Check air intake system for leaks and damage. Verify integrity of PCV system. See «POSITIVE CRANKCASE VENTILATION SYSTEM»(ref-150940-S18985781452002120200000) in «SYSTEM TESTS»(ref-150940-S42556424782002112700000). Check for vacuum leaks. If any concerns are present, repair as necessary. After repair, go to step 21. If concerns are not present, go to next step.
3. Perform KOER Self-Test Disconnect fuel vapor hose from intake manifold and plug fitting at intake manifold. Start engine and run at 2000 RPM for 5 minutes and return to idle. Perform KOER self-test. If DTC P1131 and/or P1151 is present, go to next step. If DTC P1131 and/or P1151 are not present, perform EVAP Emissions System Leak Test to locate leak. Refer to «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article.
4. HO2S Circuit Test (With Lean DTCs) Turn ignition off. Disconnect suspect HO2S 4-pin harness connector related to DTC. P1131 = HO2S11 (Front Bank 1) P1151 = HO2S21 (Front Bank 2) Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PIN/DATA MONITOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID. Connect fused jumper wire between HO2S SIG and HO2S VPWR at HO2S 4-pin harness connector. If voltage reading is 1.3 volts or more, go to next step. If voltage reading is not as specified, go to step 7. NOTE: If a spark occurs, indicating a short, remove fused jumper wire and check for short to ground (check fuse in heater circuit).
5. Check Signal Return Circuit For Shorts And Opens Measure resistance of HO2S SIG RTN circuit (Orange wire) between HO2S 4-pin harness connector and battery ground terminal. If resistance reading is less than 5 ohms, reconnect all connectors and go to step 10. If resistance reading is not as specified, repair Orange wire for open or short to ground between PCM 104-pin harness connector terminal No. 91 and HO2S 4-pin harness connector. After repair, go to next step.
6. Check HO2S Signal Return Circuit In Vehicle Harness Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of HO2S SIG RTN circuit between breakout box terminal No. 91 and HO2S 4-pin harness connector (Orange wire). If resistance reading is less than 5 ohms, replace PCM. After repair, go to step 21. If resistance reading is not as specified, repair open circuit in Orange wire between PCM 104-pin harness connector terminal No. 91 and HO2S 4-pin harness connector. After repair, go to step 21.
7. Check Resistance Of HO2S Ground Circuits Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of HO2S SIG circuit between breakout box terminal and HO2S 4-pin harness connector (Red/Black wire). Use following terminal assignment and record reading: HO2S-11 SIG = Terminal No. 60 HO2S-21 SIG = Terminal No. 87 If resistance reading is less than 5 ohms, go to next step. If resistance reading is not as specified, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 21.
8. Check HO2S Circuit Wiring Harness For Short To Ground Measure resistance of HO2S SIG circuit between breakout box terminal No. 60 or 87 and terminal No. 103 (PWR GND). Measure resistance of HO2S SIG circuit between breakout box terminal No. 60 or 87 and terminal No. 91 (SIG RTN). If each resistance reading is more than 10,000 ohms, go to next step. If each resistance reading is not as specified, repair short circuit. After repair, go to step 21.
9. Check HO2S For Short To Ground Reconnect HO2S 4-pin harness connector. Measure resistance of HO2S SIG circuit between breakout box terminal No. 60 or 87 and terminal No. 103 (PWR GND). Measure resistance of HO2S SIG circuit between breakout box terminal No. 60 or 87 and terminal No. 91 (SIG RTN). If resistance reading is more than 10,000 ohms, go to next step. If resistance reading is not as specified, repair short circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 21.
10. Check HO2S Ability To Generate A Voltage Greater Than 0.5 Volt Inspect HO2S harness for chafing, burned wiring or other damage and repair as necessary. Disconnect suspect HO2S from vehicle harness. Connect DVOM to HO2S SIG RTN or HO2S GND at HO2S sensor 4-pin connector. (Scheme 41) Run engine at 2000 RPM for 3 minutes. Run KOER self-test and monitor HO2S voltage. Turn ignition off. If voltage reading was more than 0.5 volt during or at end of Self-Test, go to next step. If voltage reading was not as specified, replace HO2S. After repair, go to step 21.
11. Monitor HO2S (PID) For Proper Switching Start engine. Warm up engine to operating temperature. Using scan, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID and monitor while wiggling, bending and shaking small sections of engine harness from HO2S to PCM. Turn ignition off. If HO2S voltage reading did not stay high (more than 0.45 volt) or low (less than 0.45 volt), go to next step. If HO2S voltage reading stayed high or low, isolate cause for lack of switching and repair as necessary. After repair, go to step 21. WARNING: Fuel system is pressurized when engine is not running. To prevent injury or fire, use caution when working on fuel system. NOTE: During next step, fuel pump will only operate for approximately 8 seconds when Output Test Mode is selected and activated.
12. Check Fuel Pressure Install fuel pressure gauge. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Access OUTPUT TEST MODE and run fuel pump to obtain maximum fuel pressure. If fuel pressure is 55-70 psi, go to next step. If fuel pressure is not as specified, refer to «FUEL DELIVERY SYSTEM»(ref-150940-S38917645432002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
13. Check Injector Fault PIDs Access INJ1F-INJ6F PIDs. If an injector(s) fault is present, go to next step. If an injector fault is not present, go to step 17. NOTE: Performing following procedure erases Continuous Memory DTCs. NOTE: Use injector fault PID to determine fuel injector circuit(s) requiring testing.
14. Check Fuel Injector(s) & Harness Resistance Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of suspect fuel injector between suspect INJ circuit breakout box terminal and breakout box terminal No. 71 (VPWR). If resistance reading is 11-18 ohms, replace PCM. After repair, go to step 21. If resistance reading is not within specification, go to next step.
15. Check Fuel Injector Harness Resistance Disconnect fuel injector harness connector at suspect fuel injector. Measure resistance of VPWR circuit (Red wire) between breakout box terminal No. 71 and fuel injector harness connector. Measure resistance of INJ circuit between appropriate breakout box terminal and fuel injector harness connector. see scheme 23 If each resistance reading is less than 5 ohms, go to next step. If each resistance reading is not as specified, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 21.
16. Check Fuel Injector Harness Circuit For Short To Power & Ground Measure resistance between suspect INJ circuit breakout box terminal and breakout box terminal No. 71 (VPWR). Measure resistance between suspect INJ circuit breakout box terminal and breakout box terminal No. 103 (PWR GND). If each resistance reading is more than 10,000 ohms, go to next step. If each resistance reading is not as specified, repair short circuit. After repair, go to step 21.
17. Flow Test Fuel Injector(s) Use a fuel injector tester to flow test fuel injectors according to instructions for tester. Flow rate specification is 17 lb/hr (7.8 kg/hr) for 2.0L engines and 22 lb/hr (10.1 kg/hr) for 3.0L engines. If leakage and flow are within specification, go to next step. If leakage and flow are not within specification, replace fuel injector(s). After repair, go to step 21.
18. Inspect Induction System For Air Leaks Inspect following areas for signs of air leaks: Inlet tube(s) from air cleaner to throttle body. Gaskets which seal upper and lower intake manifold. Vacuum hoses and lines for cracks and proper connections. PCV system. If there are no signs of leakage or damage, go to next step. If there are any signs of leaks or damage, repair as necessary. After repair, go to step 21. NOTE: Use Misfire DTCs (if present) to determine which cylinder's compression to check. Otherwise check all cylinders.
19. Check Cylinder Compression Check cylinder compression. Refer to «MECHANICAL INSPECTION»(ref-134958-S31679170122002022100000) under PRELIMINARY INSPECTION & ADJUSTMENTS in BASIC DIAGNOSTIC PROCEDURES article. If cylinder compression readings are within specification, go to next step. If cylinder compression readings are not within specification, repair as necessary. After repair, go to step 21.
20. Test Drive While Monitoring HO2S PID For Proper Switching Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITTOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID. While observer views PID, test drive vehicle under different road conditions in an attempt to simulate original fault. If HO2S appears to switch properly, unable to duplicate problem. Go to next step. If HO2S does not appear to switch properly, replace HO2S. After repair, go to next step.
21. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. DTCS P1132, P1152: Upstream HO2S(s) Not Switching Check air intake system for leaks and damage. Verify integrity of PCV system. See «POSITIVE CRANKCASE VENTILATION SYSTEM»(ref-150940-S18985781452002120200000) in «SYSTEM TESTS»(ref-150940-S42556424782002112700000). Check for vacuum leaks. If any concerns are present, repair as necessary. After repair, go to step 17. If concerns are not present, go to next step.
3. Perform KOER Self-Test Disconnect fuel vapor hose from intake manifold and plug fitting at intake manifold. Start engine and run at 2000 RPM for 5 minutes and return to idle. Perform KOER self-test. If DTC P1132 and/or P1152 is present, go to next step. If DTC P1132 and/or P1152 are not present, perform «EVAPORATIVE EMISSIONS SYSTEM LEAK TEST»(ref-134970-S31500842372002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article.
4. HO2S Circuit Test (With Rich DTCs) Turn ignition off. Disconnect suspect HO2S 4-pin harness connector related to DTC. P1132 = HO2S11 (Front Bank 1) P1152 = HO2S21 (Front Bank 2) Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PIN/DATA MONITOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID. Connect fused jumper wire between HO2S SIG (Red/Black wire) and HO2S VPWR (Light Blue/Orange wire) at HO2S 4-pin harness connector. (Scheme 41) If voltage reading is 0.2 volt or less, go to step 6. If voltage reading is not as specified, go to next step.
5. Check For Shorts To Voltage Source In Harness Circuit Turn ignition off. Disconnect scan tool from DLC. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 For DTC P1132, measure resistance between breakout box terminal No. 60 and terminals No. 71 (VPWR) and No. 93 (HTR11). For DTC 1152, measure resistance between breakout box terminal No. 87 and terminals No. 71 (VPWR) and No. 94 (HTR21). If resistance reading is more than 10,000 ohms, replace PCM. After repair, go to step 17. If resistance reading is not as specified, replace HO2S. After repair, go to step 17.
6. Check For HO2S Signal Shorted To HO2S Heater Circuit In Sensor Reconnect suspect HO2S sensor 4-pin harness connector. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID. If HO2S voltage reading is more than 0.45 volt, replace HO2S. After repair, go to step 17. If voltage reading is not as specified, go to next step. WARNING: Fuel system is pressurized when engine is not running. To prevent injury or fire, use caution when working on fuel system. NOTE: During next step, fuel pump will only operate for approximately 8 seconds when Output Test Mode is selected and activated.
7. Check Fuel Pressure Install fuel pressure gauge. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Access OUTPUT TEST MODE and run fuel pump to obtain maximum fuel pressure. If fuel pressure is 55-70 psi, go to next step. If fuel pressure is not as specified, refer to «FUEL DELIVERY SYSTEM»(ref-150940-S38917645432002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
8. Check Injector Fault PIDs Access INJ1F-INJ6F PIDs. If an injector(s) fault is present, go to next step. If an injector fault is not present, go to step 17. NOTE: Performing following procedure erases Continuous Memory DTCs. NOTE: Use injector fault PID to determine fuel injector circuit(s) requiring testing.
9. Check Fuel Injector(s) & Harness Resistance Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of suspect fuel injector between suspect INJ circuit breakout box terminal and breakout box terminal No. 71 (VPWR). If resistance reading is 11-18 ohms, replace PCM. After repair, go to step 17. If resistance reading is not within specification, go to next step.
10. Check Fuel Injector Harness Resistance Disconnect fuel injector harness connector at suspect fuel injector. Measure resistance of VPWR circuit (Red wire) between breakout box terminal No. 71 and fuel injector harness connector. Measure resistance of INJ circuit between appropriate breakout box terminal and fuel injector harness connector. see scheme 23 If each resistance reading is less than 5 ohms, go to next step. If each resistance reading is not as specified, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 17.
11. Check Fuel Injector Harness Circuit For Short To Power & Ground Measure resistance between suspect INJ circuit breakout box terminal and breakout box terminal No. 71 (VPWR). Measure resistance between suspect INJ circuit breakout box terminal and breakout box terminal No. 103 (PWR GND). If each resistance reading is more than 10,000 ohms, go to next step. If each resistance reading is not as specified, replace fuel injector(s). After repair, go to step 17.
12. Flow Test Fuel Injector(s) Use a fuel injector tester to flow test fuel injectors according to instructions for tester. Flow rate specification is 17 lb/hr. (7.8 kg/hr.) for 2.0L engines and 22 lb/hr. (10.1 kg/hr.) for 3.0L engines. If leakage and flow are within specification, go to next step. If leakage and flow are not within specification, replace fuel injector(s). After repair, go to step 17.
13. Attempt To Generate DTCS P1131 & P1151 Disconnect suspect HO2S 4-pin harness connector. Install fused jumper wire between negative battery post and HO2S 4-pin harness connector HO2S SIG terminal. Perform KOER self-test. If DTCs P1131 or P1151 are present, remove fused jumper wire and go to next step. If DTCs P1131 or P1132 are not present, remove fused jumper wire. Reconnect HO2S 4-pin harness connector. Disconnect PCM 104-pin harness connector. Inspect both ends for damaged or pushed out terminals, corrosion and loose wires. Repair as necessary. If connector, terminals and wiring are okay. Replace PCM. After repair, go to step 17.
14. HO2S Check Connect DVOM to HO2S SIG and HO2S SIG RTN terminals at HO2S sensor 4-pin connector. (Scheme 41) Disconnect any vacuum hose. Start engine and run at 2000 RPM. If voltage reading indicates less than 0.4 volt within 30 seconds, reconnect vacuum line and go to next step. If voltage reading is not as specified, replace HO2S. After repair, go to step 17.
15. Monitor HO2S (PID) For Proper Switching Start engine. Warm up engine to operating temperature. Using scan, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID and monitor while wiggling, bending and shaking small sections of engine harness from HO2S to PCM. Turn ignition off. If HO2S voltage reading did not stay high (more than 0.45 volt) or low (less than 0.45 volt), go to next step. If HO2S voltage reading stayed high or low, isolate cause for lack of switching and repair as necessary. After repair, go to step 21.
16. Test Drive While Monitoring HO2S PID For Proper Switching Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. Access O2S11 (Front Bank 1) or O2S21 (Front Bank 2) PID. While observer views PID, test drive vehicle under different road conditions in an attempt to simulate original fault. If HO2S appears to switch properly, unable to duplicate problem. Go to next step. If HO2S does not appear to switch properly, replace HO2S. After repair, go to next step.
17. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. Check All Other Passive Anti-Theft System (PATS) DTCs Repair all other PATS DTCs before DTC P1260. Refer to SELF-DIAGNOSTIC SYSTEM in appropriate IMMOBILIZER SYSTEM - PASSIVE ANTI-THEFT SYSTEM - TRIBUTE article in ACCESSORIES & EQUIPEMENT. After all other PATS DTCs have been diagnosed, go to next step.
2. Check For Other Powertrain DTCs Repair all other powertrain DTCs before P1260. Refer to «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . After all other powertrain DTCs have been diagnosed, go to next step. NOTE: PATS cannot stall engine after one second of operation.
3. Attempt To Start Engine Complete Keep Alive Random Access Memory (KAM). Reset to clear DTC 1260. This reset initializes PCM to communicate with PATS. Attempt to start engine. If engine starts, problem is intermittent. For intermittent Stalls while driving, verify scan tool to PCM communication during concern. If PCM communication error occurs, possible causes are: Loss of PWRS or GNDS to PCM. Faulty PCM PWR relay. Faulty EEC PWR diode. Repair as necessary and return vehicle to customer. If engine does not start, DTC P1260 is not cause of No Start. Refer to SYSTEM TESTS in appropriate GENERATORS & REGULATORS article in ELECTRICAL.

Check Vehicle Operation - Check for

1. Water, ice, mud and snow causing wheel slippage.
2. Excessive engine RPM in N (Neutral).
3. Driven at high rate of speed.

If vehicle was operating in any of these conditions, vehicle is okay. Clear DTC and return vehicle to customer with information about P1270. If vehicle was not operating in any of these conditions, clear DTC and refer to SYMPTOM DIAGNOSIS in TROUBLE SHOOTING - NO CODES article to address any driveability concerns.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Check CMP Sensor Output Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector and PCM. see scheme 2 Start engine and vary engine RPM. Measure voltage between breakout box terminal No. 85 (CMP) and terminal No. 103 (PWR GND). If AC voltage reading varies more than 0.1 volt, verify correct installation of CMP sensor. If CMP sensor installation is correct, replace PCM. After repair, go to next step. If AC voltage reading does not vary more than 0.1 volt, replace CMP sensor.
3. Verify Troubleshooting Of DTCs Completed Make sure to reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool generic OBD-II function. Perform «Fuel Or Misfire Monitor Repair Verification Drive Cycle»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If same DTC is present, replace PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step. NOTE: If DTC P1406 is currently present, DTC P1408 will also appear in Key ON, Engine Running (KOER) Self-Test.
2. Inspect Pressure Hose Connections Inspect upstream or downstream hose at DPFEGR sensor and orifice tube assembly for disconnect or poor connection. If hose is off or poorly connected, repair as necessary. After repair, go to step 7 . NOTE: It is essential that DPFEGR pressure hose is the correct service part and not a substitute.
3. Inspect Pressure Hose For Plugging Visually inspect upstream or downstream hose routing. Hose should not be pinched or have dips in it where water could settle and freeze. Remove upstream or downstream hose and carefully inspect for plugging, water or leaks. If a fault is detected in hose, repair or replace hose as necessary. After repair, go to step 7 .
4. Check Orifice Tube Assembly & DPFEGR Sensor Inspect connections at DPFEGR sensor for plugging or damage. Inspect exhaust and intake manifold side pressure pickup tube and orifice tube assembly for plugging, loose connection or damage. If no problem is found with DPFEGR sensor or orifice tube, go to next step. If DPFEGR sensor or orifice tube assembly is plugged, loose or damaged, repair or replace DPFEGR sensor or orifice tube assembly as necessary. After repair, go to next step.
5. Check DPFEGR Sensor Output By Applying Vacuum With Hand Pump Disconnect pressure hoses at DPFEGR sensor. Connect a hand vacuum pump to downstream connection at sensor (intake manifold side of sensor or smaller diameter pickup tube). Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. Access DPFEGR PID and note PID value. Apply 8-9 in. Hg (27-30 kPa) vacuum to DPFEGR sensor and hold for a few seconds. Quickly release vacuum. DPFEGR PID voltage reading must be 0.2-1.3 volts with ignition on and no vacuum applied. DPFEGR PID voltage reading must increase to more than 4.0 volts with vacuum applied. DPFEGR PID voltage reading should drop to less than 1.5 volts in less than 3 seconds when vacuum is released. Turn ignition off. If DPFEGR PID voltage reading indicates a fault in DPFEGR sensor, replace DPFEGR sensor. After repair, go to next step. If DPFEGR PID voltage reading does not indicate a fault in DPFEGR sensor, problem is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000) .
6. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «EVAPORATIVE EMISSION REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S36910449522003010300000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. Retrieve pending code. If same DTC present, replace PCM. After repair, go to next step. If same DTC is not present, go to next step.
7. Verify Trouble Shooting Of DTCs Completed Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed and KOEO and KOER DTC P1409 is present, go to next step. If Continuous Memory DTC P1409 is present, go to step 7.
2. DTC P1409: Measure Resistance Across EGRVR Solenoid Disconnect EGRVR solenoid harness connector. Measure EGRVR solenoid resistance. If solenoid resistance reading is 26-40 ohms, go to next step. If solenoid resistance is not as specified, replace EGRVR solenoid. After repair, go to step 8.
3. Check VPWR Circuit Voltage At EGRVR Solenoid Turn ignition on, engine off. Measure voltage between ground and VPWR circuit (White/Red wire) at EGRVR solenoid harness connector. see scheme 17 Turn ignition off. If voltage reading is more than 10.5 volts, go to next step. If voltage reading is 10.5 volts or less, repair open in VPWR circuit (Red/White wire) between EGRVR solenoid harness connector and PCM 104-pin harness connector terminal No. 71. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
4. Check EGRVR Circuit Resistance Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of EGRVR circuit between breakout box terminal No. 79 (2.0L) or No. 47 (3.0L) and EGRVR solenoid harness connector (Violet wire). If resistance reading is less than 5.0 ohms, go to next step. If resistance reading is 5.0 ohms or more, repair open in EGRVR circuit (Violet wire) between EGRVR solenoid harness connector and PCM 104-pin harness connector terminal No. 79 (2.0L) or No. 47 (3.0L). After repair, go to step 8.
5. Check EGRVR Circuit For Short To Power In Harness Turn ignition on, engine off. Measure voltage of EGRVR circuit between breakout box terminal No. 79 (2.0L) or No. 47 (3.0L) and negative battery post. If voltage reading is less than one volt, turn ignition off. Go to next step. If voltage reading is not as specified, repair short to power in Violet wire between EGRVR solenoid harness connector and PCM 104-pin harness connector terminal No. 79 (2.0L) or No. 47 (3.0L). After repair, go to step 8.
6. Check EGRVR Circuit For Shorts To Ground Measure resistance between breakout box terminal No. 79 (2.0L) or No. 47 (3.0L) (EGRVR) and terminals No. 24 and 103 (PWR GND). If resistance reading is more than 10,000 ohms, replace PCM. After repair, go to step 8. If resistance reading is not as specified, repair short in Violet wire between EGRVR solenoid harness connector and PCM 104-pin harness connector terminal No. 79 (2.0L) or No. 47 (3.0L). See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 8.
7. Wiggle EGRVR Solenoid While Monitoring VPWR Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of EGRVR circuit between breakout box terminal No. 79 (2.0L) or No. 47 (3.0L) and terminal No. 24 (PWR GND). Voltage reading must be more than 10.5 volts. For an indication of a fault, look for this voltage to drop while performing following: Lightly tap on EGRVR solenoid. Wiggle EGRVR solenoid connector. Grasp EGRVR solenoid connector and wiggle wires between solenoid and PCM. If a fault is indicated, isolate fault and repair as necessary. After repair go to next step. If no fault is indicated, fault is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
8. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Check For Visual Causes Of Excessive Fuel Tank Vacuum Check for kinks or bends in fuel vapor hoses and tubes. Visually inspect EVAP canister inlet port, canister vent solenoid, EVAP dust separator or outlet hose for contamination or foreign material. If a concern is not evident, go to next step. If a concern is evident, remove any contamination or foreign material around fuel vapor hoses and tubes. Repair as necessary. After repair, go to step 7 .
3. Perform EVAP Leak Test Connect EVAP Leak Tester to fuel filler pipe. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Close EVAP Canister Vent (CV) solenoid by accessing OUTPUT TEST MODE. Pressurize EVAP system to 14 in. H 2 O (3.48 kPa). If pressure reaches 14 in. H 2 O (3.48 kPa), go to next step. If pressure does not reach 14 in. H 2 O (3.48 kPa), check if EVAP vapor management valve is stuck open. Replace if necessary. After repair, go to step 7
4. Check For Canister Vent Solenoid Stuck Closed Press STOP (#4 button) to open CV solenoid. If pressure drops immediately, go to next step. If pressure does not drop immediately, go to «HISSING SOUND WHEN REMOVING FUEL CAP»(ref-134970-S11652989262002022100000) under SYSTEM TESTS (EVAPORATIVE EMISSION) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article.
5. Check For Fuel Tank Pressure Sensor PID Without Pressure Applied Disconnect EVAP canister outlet tube at EVAP canister. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Access FTP V PID and record reading. If FTP V PID voltage reading is 2.40-2.80 volts, go to next step. If FTP V PID voltage reading is not as specified, replace Fuel Tank Pressure (FTP) sensor. After repair, go to next step.
6. EVAP System Leak Test Connect all disconnected connectors and hoses. Perform EVAP system leak test. Refer to «SYSTEM TESTS (EVAPORATIVE EMISSION)»(ref-134970-S09458215942002022100000) in SYSTEM & COMPONENT TESTING - B2300, B3000, B4000 & TRIBUTE article. If test result is okay, go to step 8 . If test result is not okay, locate leak and repair. Repeat this step.
7. Drive Cycle Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «EVAPORATIVE EMISSION REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S36910449522003010300000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. Retrieve pending code. If same DTC present, replace PCM. After repair, go to next step. If same DTC is not present, go to next step.
8. Verify Trouble Shooting Of DTCs Completed Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If any DTC is present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000) . If no DTCs are set, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, proceed as follows: If DTC P1474 is present, go to step 10. If DTC P1477 is present, go to step 12. If DTC P1479 is present, go to step 14 (for 2.0L) or go to step 7 (for 3.0L). For all others, go to next step.
2. Check VPWR (IGN START/RUN) Voltage To Applicable Fan Relay Disconnect appropriate fan control relay: DTC 1474: LFC DTC 1477: MFC DTC 1479: HFC Turn ignition on, engine off. Measure VPWR (IGN START/RUN) circuit voltage at applicable fan control relay harness connector. See «WIRING DIAGRAMS»(ref-134975) article. If voltage reading is more than 10.5 volts, go to next step. If voltage reading is not as specified, repair open in VPWR (IGN START/RUN) circuit to applicable fan control relay. After repair, go to step 16. NOTE: Commanding LFC PID on will also command MFC PID output on if MFC PID is not available.
3. Check For LFC, MFC Or HFC Circuit Cycling Connect a non-powered test light between VPWR circuit (White/Violet wire) and LFC, MFC or HFC circuit at the applicable fan control relay 5-pin harness connector. See «WIRING DIAGRAMS»(ref-134975) article. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Select OUTPUT TEST MODE. While observing test light, command appropriate cooling fan (LFC, MFC or HFC PIDs) speed on and off. If test light does not turn on and off when cooling fan output is commanded on and off, repeat test to verify results. If test results are same, remove testlight. Turn ignition off and go to next step. If test light turns on and off when cooling fan output is commanded on and off, replace appropriate fan control relay. After repair, go to step 16.
4. Check LFC, MFC Or HFC Circuit For Short To Power In Harness Disconnect PCM 104-pin harness connector. Turn ignition on, engine off. Measure voltage between ground and LFC, MFC or HFC circuit at applicable fan relay 5-pin harness connector. If voltage reading is less than one volt, go to next step. If voltage reading is not as specified, repair short to power between PCM 104-pin harness connector and appropriate fan control relay 5-pin harness connector. After repair, go to step 16.
5. Check LFC Or HFC Circuit For Short To Ground In Harness Turn ignition off. Disconnect scan tool. Measure resistance between ground and LFC, MFC or HFC circuit at applicable fan control relay harness connector. If resistance reading is more than 10,000 ohms, go to next step. If resistance reading is not as specified, repair short circuit between PCM 104-pin harness connector and appropriate fan control relay. After repair, go to step 16.
6. Check For Open LFC, MFC Or HFC Circuit Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of LFC, MFC or HFC circuit between breakout box terminal and appropriate fan control relay harness connector. LFC - breakout box terminal No. 68 (2.0L) or No. 28 (3.0L). MFC - breakout box terminal No. 43 (2.0L) or No. 42 (3.0L). HFC - breakout box terminal No. 17 (2.0L) or No. 46 (3.0L). If resistance reading is less than 5.0 ohms, replace PCM. After repair, go to step 16. If resistance reading is not as specified, repair open circuit between PCM 104-pin harness connector and appropriate fan control relay terminal No. 2.
7. Check Ignition START/RUN Circuit Voltage To High Speed FC Relay No. 1 Disconnect HFC relay No. 1 (MAIN FAN relay in battery junction box). Turn ignition on, engine off. Measure VPWR (IGN START/RUN) circuit voltage at applicable fan control relay 5-pin harness connector (White Violet wire). See «WIRING DIAGRAMS»(ref-134975) article. If voltage reading is more than 10.5 volts, go to next step. If voltage reading is not as specified, repair open in IGN START/RUN circuit (White/Violet wire) between PCM power relay and HFC relay No. 1. After repair, go to step 16.
8. Check For HFC Circuit Cycling At High Speed FC Relay No. 1 Connect a non-powered test light between VPWR circuit and LFC, MFC or HFC circuit at applicable fan control relay 5-pin harness connector. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Select OUTPUT TEST MODE. While observing test light, command high speed cooling fan on and off (using HFC PID). If test light turns on and off when cooling fan output is commanded on and off, replace HFC relay No. 1. After repair, go to step 16. If test light does not turn on and off when cooling fan output is commanded on and off, leave test light connected and go to next step.
9. Check For HFC Circuit Cycling With High Speed FC Relay No. 2 Disconnected Disconnect HFC relay No. 2 (ADD FAN relay in battery junction box). While observing test light, command high speed cooling fan on and off (using HFC PID). If test light turns on and off when cooling fan output is commanded on and off, replace HFC relay No. 2. After repair, go to step 16. If test light does not turn on and off when cooling fan output is commanded on and off, go to step 4 to diagnose HFC circuit. Make checks at HFC relay No. 1 5-pin harness connector.
10. Check Low Speed Fan Control (LFC) Circuit For Open Or Short To Power Verify A/C and defrost are off. Disconnect cooling fan 3-pin harness connectors. Connect a non-powered test light between (LOW) FAN PWR circuit (Gray/Red wire) and ground circuit at cooling fan 3-pin harness connector. Toggle load on and off (headlights). For 2.0L, use driver's side fan. For 3.0L, use passenger's side fan. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Select OUTPUT TEST MODE. Command LOW SPEED FAN on (using LFC PID). Observe test light for an indication of a fault while completing following (the lamp will turn off when a fault is detected, indicating an open or short to power): Shake, wiggle and bend LFC circuit between PCM and LFC relay. Shake, wiggle and bend VPWR (IGN START/RUN) circuit to LFC relay. Lightly tap on LFC relay to simulate road shock. If no fault is indicated, go to next step. If a fault is indicated, isolate fault and repair as necessary. After repair, go to step 16.
11. Check LFC Circuit For Short To Ground Command LFC relay off (using LFC PID). Observe test light for an indication of a fault while completing following (test lamp will turn on when a fault is detected, indicating LFC circuit short to ground): Shake, wiggle and bend the LFC circuit between the PCM and low speed FC relay. Lightly tap on the low speed FC relay to simulate road shock. If a fault is indicated, isolate fault and repair as necessary. After repair, go to step 16. If a fault is not indicated, fault is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under SYSTEM TESTING.
12. Check Medium Speed Fan Control (MFC) Circuit For Open Or Short To Power Verify A/C and defrost are off. Disconnect cooling fan 3-pin harness connectors. Connect a non-powered test light: For 2.0L, connect test light between MEDIUM FAN PWR circuit (Light Blue/Black wire) and ground circuit at passenger-side cooling fan 3-pin harness connector. For 3.0L, disconnect MFC relay (located on left front of radiator core support) and connect test light between MFC circuit (Black wire) and IGN START/RUN circuit (White/Violet wire) at MFC relay 5-pin harness connector. NOTE: Commanding LFC PID on will also command MFC PID output on if MFC PID is not available. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Select OUTPUT TEST MODE. Command medium speed fan on (using LFC or MFC PID). Observe test light for an indication of a fault while completing following (lamp will turn off when a fault is detected, indicating an open or short to power): Shake, wiggle and bend MFC circuit between PCM and MFC relay. Shake, wiggle and bend VPWR (IGN START/RUN) circuit to MFC relay. For 2.0L, lightly tap on MFC relay to simulate road shock. If a fault is not indicated, go to next step. If a fault is indicated, isolate fault and repair as necessary. After repair, go to step 16.
13. Check MFC Circuit For Short To Ground Command low speed fan off (using LFC or MFC PID). Observe test light for an indication of a fault while completing following (lamp will turn on when a fault is detected, indicating MFC circuit short to ground): Shake, wiggle and bend MFC circuit between PCM and MFC relay. For 2.0L, lightly tap on MFC relay to simulate road shock. For 3.0L, inspect MFC relay for intermittent concerns. If a fault is indicated, isolate fault and repair as necessary. After repair, go to step 16. If a fault is not indicated, problem is intemittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
14. Check High Speed Fan Control (HFC) Circuit For Open Or Short To Power Verify A/C and defrost are off. Disconnect cooling fan 3-pin harness connectors. Connect a non-powered test light between (HIGH) FAN PWR circuit and ground circuit at cooling fan harness connector. For 2.0L, use driver's side fan. For 3.0L, use passenger's side fan. Turn ignition on, engine off. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select ACTIVE COMMAND MODES. Select OUTPUT TEST MODE. Command high speed fan on (using HFC PID). Observe test light for an indication of a fault while completing following (lamp will turn off when a fault is detected, indicating an open or short to power): Shake, wiggle and bend HFC circuit between PCM and HFC relay. Shake, wiggle and bend VPWR (IGN START/RUN) circuit to HFC relay. Lightly tap on HFC relay to simulate road shock. If a fault is not indicated, go to next step. If a fault is indicated, isolate fault and repair as necessary. After repair, go to step 16.
15. Check HFC Circuit For Short To Ground Command high speed fan off (using HFC PID). Observe test light for an indication of a fault while completing following (lamp will turn on when a fault is detected, indicating HFC circuit short to ground): Shake, wiggle and bend HFC circuit between PCM and HFC relay. Lightly tap on HFC relay to simulate road shock. If a fault is not indicated, replace generator/regulator assembly. After repair, go to next step. If fault is indicated, isolate fault and repair as necessary. After repair, go to next step.
16. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. DTC P1506: Check For Vacuum Leaks Start engine. With engine at idle, listen for vacuum leaks. Inspect entire intake air system from Mass Airflow (MAF) sensor to intake manifold for damage or leaks such as: Cracked or punctured intake air tube. Loose or cracked IAC air tubes. Loose intake air tube at the air cleaner housing or throttle body. IAC valve assembly or gasket seal. Intake manifold assembly or gasket seal. EGR valve gasket seal. Vacuum supply connectors and hose. PCV valve, connectors and hoses. Turn ignition off. If no leaks were detected, go to next step. If any leaks were detected, repair or replace components as necessary. After repair, go to step 7.
3. Check EVAP System For A Stuck Open Valve Disconnect hoses at EVAP canister purge valve. Connect hand vacuum pump at fuel vapor port of EVAP canister at EVAP canister purge valve. Apply 16 in. Hg (53 kPa) of vacuum to EVAP canister purge valve. If EVAP canister purge valve holds vacuum for 20 seconds, reconnect all components and go to next step. If EVAP canister purge valve did not hold vacuum for 20 seconds, replace EVAP canister purge valve.
4. Check EVAP System For A Stuck Open Valve Start engine. Bring engine to normal operating temperature. Transaxle in park or neutral. Disconnect IAC valve harness connector. Turn ignition off. If RPM dropped or engine stalled, go to next step. If RPM did not drop, inspect for throttle body damage. If throttle body is okay, replace Idle Air Control (IAC) valve. If throttle body is not okay, repair or replace throttle body. After repair, go to step 7.
5. Check IAC Circuit For Short To Ground Disconnect scan tool from DLC. Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance between breakout box terminal No. 83 (IAC) and terminals No. 51 and 103 (PWR GND). If resistance reading is more than 10,000 ohms and fast idle symptom is present, replace PCM. After repair, go to step 7. For all others, go to next step. If resistance reading is not as specified, repair short in IAC SIG circuit (White/Light Blue wire). See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 7.
6. Check IAC System For Intermittent Open Or Short Connect scan tool. Start engine. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. Access IAC PID and RPM PIDs. With engine at normal operating temperature, accessories off and at idle, IAC duty cycle must be 20-45percent. Observe PIDs for an indication of a fault while performing following at idle: Lightly tap on IAC valve assembly and wiggle harness connector to simulate road shock. Grasp vehicle harness closest to IAC valve assembly. Shake and bend a small section of harness from IAC to dash panel and from dash panel to PCM. If IAC or RPM PIDs suddenly change in value indicating a fault, isolate fault and repair as necessary. After repair, go to next step. If IAC or RPM PIDs do not change, for idle, starting or stalling symptoms currently present, replace IAC solenoid. After repair, go to next step. For all other concerns, refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
7. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

1. If QUICK TEST was not performed, go to «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If QUICK TEST was performed, go to next step.
2. Verify Electrical Function Start enigne. Using scan tool, select DIAGNOSTIC DATA LINK. Select PCM. Select PID/DATA MONITOR AND RECORD. View PSP PID while turning steering wheel back and forth. If PSP PID does not indicate Low/High or High/Low, go to next step. If PSP PID indicates Low/High or High/Low, problem is intermittent. Refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000).
3. Check For PSP Switch Cycling Disconnect PSP switch. Install a fused jumper wire between PSP switch harness connector terminals. Start engine. Record PSP PID reading. Access PID/DATA MONITOR AND RECORD. Remove fused jumper wire and record PSP PID reading. Turn ignition off. If PSP PID does not change from high to low, go to next step. If PSP PID changes from high to low, replace PSP switch. After repair, go to step 6.
4. Check Continuity Of PSP Circuits Disconnect PCM 104-pin harness connector. Connect Breakout Box (49-UN01-130) to PCM harness connector only. see scheme 2 Measure resistance of PSP circuit between breakout box terminal No. 31 and PSP switch harness connector (Yellow/Light Green wire). Measure resistance of SIG RTN circuit between breakout box terminal No. 91 and PSP switch harness connector (Orange wire). If each resistance reading is less than 5.0 ohms, go to next step. If each resistance reading is not as specified, repair open circuit. See «WIRING DIAGRAMS»(ref-134975) article. After repair, go to step 6.
5. Check PSP Circuit For Short Measure resistance between breakout box terminals No. 31 (PSP) and No. 91 (SIG RTN). Measure resistance between ground and breakout box terminal No. 31 (PSP). If either resistance reading is less than 10,000 ohms, repair short in harness. After repair, go to next step. If either resistance reading is not as specified, replace PCM. After repair, go to next step.
6. Verify Trouble Shooting Of DTCs Completed Reconnect all disconnected connectors. Clear DTCs from PCM memory using scan tool. Perform «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is present, replace faulty PCM. Repeat «QUICK TEST»(ref-150940-S17451707022002112700000) under SELF-DIAGNOSTIC SYSTEM. If same DTC is not present, go to applicable procedure for other DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-150940-S42582837182002112700000). If no DTCs are present, trouble shooting is complete.

FUEL PUMP INSPECTION

1. Check Fuel Pump For Operation Verify battery is fully charged. Verify fuel tank unit 4-pin harness connector is securely connected. Turn ignition on, engine off. Connect scan tool to DLC. Select PCM, ACTIVE COMMAND MODE, OUTPUT TEST MODE and fuel pump PID. Press MODE to change to ALL ON MODE. Press START to run fuel pump and listen for fuel pump operation. Press STOP. If fuel pump operation was heard, go to «FUEL DELIVERY SYSTEM»(ref-150940-S38917645432002120200000) testing for more trouble shooting procedures. If fuel pump operation is not heard, go to next step.
2. Check Fuel Pump For Continuity Turn ignition off. Disconnect fuel tank unit 4-pin harness connector. Check for continuity between fuel tank unit 4-pin connector power terminal (Pink/Black wire) and ground terminal (Black wire). See «WIRING DIAGRAMS»(ref-134975) article. If continuity present is present, go to next step. If continuity is not present, replace fuel pump module.
3. Check Voltage At Fuel Pump (Vehicle Harness Connected) Turn ignition on, engine off. Select DIAGNOSTIC DATA LINK, PCM, ACTIVE COMMAND MODE, OUTPUT TEST MODE and fuel pump PID. Press MODE to change to ALL ON MODE. Press START to run fuel pump and measure the voltage at fuel tank unit 4-pin connector power terminal (Pink/Black wire). Press STOP. If voltage is more than 10.5 volts, go to next step. If voltage reading is 10.5 volts or less, check fuel pump relay or Inertia Fuel Shut-off (IFS) switch.
4. Check Fuel Pump Ground Circuit Disconnect fuel tank unit 4-pin harness connector. Measure resistance between fuel tank unit 4-pin connector ground terminal (Black wire) and chassis ground. If resistance is less than one ohm, ground circuit is okay. Recheck fuel pump. If resistance reading is one ohm or more, repair open in Black wire between tank unit 4-pin harness connector and chassis ground.

FUEL LINE/FUEL PRESSURE HOLD INSPECTION

1. Check Fuel Pressure Install Fuel Pressure Gauge. Turn ignition on, engine off. Connect scan tool to DLC. Select DIAGNOSTIC DATA LINK, PCM, ACTIVE COMMAND MODE, fuel pump PID and OUTPUT TEST MODE. Press MODE to change to ALL ON MODE. Press START to run fuel pump and observe fuel pressure. If fuel pressure is 55-70 psi (380-482 kPa)
2. Check Fuel Pressure After One Minute Observe fuel pressure after one minute. Press STOP. If fuel pressure is within 5 psi (34 kPa) of previous reading, fuel pressure hold inspection is okay. If fuel pressure is not within 5 psi (34 kPa) of previous reading, check for fuel injector leakage.

FUEL INJECTOR INSPECTION

1. Listen For Injector Operation Warm up engine and run at idle (or cranking if engine will not start). Listen for "clicking" sound from fuel injectors (use stethoscope if necessary). If all fuel injectors are "clicking", go to step 3 . If all fuel injectors are not "clicking", go to next step.
2. Check Injector Resistance Disconnect suspect injector connectors. Measure resistance of injectors. If resistance reading is 11-18 ohms at 68°F (20°C), check injector driver circuits from PCM. WARNING: Before performing following operation, release fuel pressure from fuel system to reduce possibility of injury or fire. See «FUEL PRESSURE RELEASE»(ref-134958-S02405930982002022100000) under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article.
3. Check Injectors For Fuel Leakage Remove fuel rail assembly from intake manifold. Connect fuel lines. Disconnect Inertia Fuel Shutoff (IFS) switch 3-pin harness connector. Install fused jumper wire between battery positive and IFS switch terminal No. 2 (Pink/Black wire) to run fuel pump. See «WIRING DIAGRAMS»(ref-134975) article. Check for fuel leaks from injectors. If fuel leakage is less than one drop per 2 minutes, fuel injectors are okay. If fuel leakage is more than one drop per 2 minutes, replace leaking fuel injector. Replace O-rings and check for fuel rail damage. Repair or replace as necessary.

EGR VACUUM REGULATOR SOLENOID INSPECTION

1. Check EGR Vacuum Regulator (EGRVR) Solenoid Output By Applying Vacuum With Hand Pump Disconnect vacuum hoses from solenoid. Connect hand vacuum pump to port "A" of EGRVR solenoid. Plug port "B". Apply vacuum to port "A". If vacuum holds, go to next step. If vacuum does not hold, replace EGRVR solenoid. CAUTION: Never apply voltage to terminal "B". The diode in the solenoid may be damaged.
2. Check EGRVR Solenoid Vacuum Output Capability Apply vacuum to port "A". Apply battery voltage to terminal "A" and ground terminal "B". If vacuum holds and releases when solenoid is energized, EGRVR is okay. If vacuum does not hold and release when solenoid is energized, replace EGRVR solenoid.

IGNITION SCOPE TEST

Scheme 43

Scheme 44

Scheme 45

Scheme 46

Scheme 47

Scheme 48

Scheme 49

1. Visual Inspection Of Ignition System Visually inspect the engine compartment to make sure all coils and spark plug wires are properly and securely connected. Examine all wiring harnesses and connectors for damaged, burned or overheated insulation and loose or broken conditions. Ensure battery is fully charged. All accessories must be off during diagnosis. If a problem is indicated, Repair as necessary. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If a problem is not indicated, for diagnosis with engine analyzer, go to next step. For diagnosis without engine analyzer, go to step 10. NOTE: In order for diagnostic procedures to provide accurate results, it is essential that calibration of the engine analyzer be maintained. Refer to equipment manual for procedure to calibrate engine analyzer. If equipment manual is not available, an estimate of the calibration can be made by connecting Spark Tester (303-D037) or equivalent to a properly operating ignition system and measuring firing voltage of spark tester only. Spark tester firing voltage should be approximately 28KV.
2. Connect Engine Analyzer Obtain Engine Analyzer (010-01060) or an equivalent to diagnose concerns in secondary side of ignition system. After engine analyzer is connected to vehicle, go to next step.
3. Check For Ignition Pattern Observe pattern on scope while cranking engine. (Scheme 43) If pattern is flat, which indicates no spark on all cylinders, turn ignition off. Check condition of related fuses/fuse links. If okay, repair open circuit. If fuse/fuse link is damaged, check IGN START/RUN circuit for short to ground. Repair as necessary. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If pattern is not flat, go to next step. NOTE: Spark plugs are fired up to four strikes per firing. Multi-strike operating mode is dependent on PCM calibration and is limited to less than 2000 RPM. Above 2000 RPM, spark plugs are fired once per firing.
4. Check For Normal Ignition Pattern Start engine. Check spark plug firing voltage average and evenness of patterns. (Scheme 44) If patterns are even and average value of spark plug firing voltage is 20KV or more with evenness of spark plug firing voltage within 8KV or less, proceed as follows: If directed here from TROUBLE SHOOTING - NO CODES article, return to «SYMPTOM DIAGNOSIS»(ref-134968-S36579230062002022100000) in TROUBLE SHOOTING - NO CODES article. If directed here from step 6) of NO START - TEST, return to step 7. All others, go to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing. If ignition pattern and values are not normal as specified, go to next step.
5. Check For Two Missing Spark Patterns On The Same Coil Observe pattern on scope. (Scheme 45) If spark pattern is missing from two cylinders on same coil, proceed as follows: Inspect spark plug wires and spark plugs for missing cylinders. Measure resistance of spark plug wires (2.0L). Replace wire(s) if resisitance reading is more than 7000 ohms per foot. Measure resistance of spark plugs. Replace if resistance is lower than 2000 ohms or higher than 20,000 ohms. If spark plug wires and spark plugs are OK, go to «DTC P0350: IGNITION COIL PRIMARY CIRCUIT - MALFUNCTION»(ref-150940-S25344015032002112700000) under DIAGNOSTIC TESTS. If spark pattern is not missing from two cylinders on same coil, go to next step.
6. Check For One Missing Spark Pattern Observe pattern on scope. (Scheme 46) If spark pattern is missing from one cylinder, proceed as follows: Inspect spark plug wire (2.0L) and spark plug for missing cylinder. Measure resistance of spark plug wire (2.0L). Replace wire if resistance is more than 7000 ohms per foot. Measure resistance of spark plugs. Replace if resistance is lower than 2000 ohms or higher than 20,000 ohms. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If spark pattern is not missing, go to next step.
7. Check For High Spark Plug Firing Voltage Check spark plug firing voltage average and evenness. (Scheme 47) If average value of spark plug firing voltage is more than 20KV with evenness of spark plug voltage within 8KV or less, conditions affect all cylinders. Proceed as follows: Inspect spark plug wires (2.0L) and spark plugs. Measure resistance of spark plug wires (2.0L). Replace if resistance is more than 7000 ohms per foot. Measure resistance of spark plugs. Replace if resistance is lower than 2000 ohms or higher than 20,000 ohms. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If spark pattern is not as specified, go to next step.
8. Check For Low Spark Plug Firing Voltage Check spark plug firing voltage average and evenness. (Scheme 48) If there is consistently low spark plug firing voltage or sloping spark line on one or more cylinders, proceed as follows: Inspect spark plug wires (2.0L) and spark plugs. Measure resistance of spark plug wires (2.0L). Replace if resistance is more than 7000 ohms per foot. Measure resistance of spark plugs. Replace if resistance is lower than 2000 ohms or higher than 20,000 ohms. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If spark pattern is not as specified, go to next step.
9. Check For Evenness Between Cylinders Check spark plug firing voltage average and evenness. (Scheme 49) If evenness of spark plug firing voltage is more than 8KV, proceed as follows: Inspect spark plug wires (2.0L) and spark plugs. Measure resistance of spark plug wires (2.0L). Replace if resistance is more than 7000 ohms per foot. Measure resistance of spark plugs. Replace if resistance is lower than 2000 ohms or higher than 20,000 ohms. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If spark pattern is not as specified, go to next step.
10. DTC P0301-P0306: MISFIRE ON CYLINDERS 1-6 If any misfire DTCs are present, go to next step. If misfire DTCs are not present, go to step 12.
11. Check For Spark At Cylinder(s) Indicated By DTC(s) Disable Inertia Fuel Shutoff (IFS) switch. Disconnect spark plug wire from each spark plug (2.0L). Connect Spark Tester (303-D037 or D81P-6666-A) or equivalent to spark plug wire (2.0L) or to ignition coil (3.0L). Check for spark while cranking engine. If Bluewish-White spark is present, turn ignition off and go to step 13. If Bluewish-White spark is not present, turn ignition off and proceed as follows: Inspect spark plug wires (2.0L). Measure resistance of spark plug wires (2.0L). Replace if resistance is more than 7000 ohms per foot. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If spark plug wires are okay, refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing under «SYSTEM TESTS»(ref-150940-S42556424782002112700000). If spark pattern is not as specified, go to next step.
12. Check For Spark At All Cylinders Disable Inertia Fuel Shutoff (IFS) switch. Disconnect spark plug wire from each spark plug (2.0L). Connect Spark Tester (303-D037 or D81P-6666-A) or equivalent to spark plug wire (2.0L). Check for spark while cranking engine. If Bluewish-White spark is present at all cylinders, turn ignition off and go to step 13. If Bluewish-White spark is not present at all cylinders, turn ignition off and proceed as follows: Inspect spark plug wires (2.0L). Measure resistance of spark plug wires (2.0L). Replace if resistance is more than 7000 ohms per foot. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES. If spark plug wires are okay, refer to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing. If spark pattern is not as specified, go to next step.
13. Check Spark Plugs Remove and check plugs for damage, wear, carbon deposits and proper plug gap. If spark plugs are okay, go to next step. If spark plugs are not okay, adjust gap or replace as necessary. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES.
14. Measure Spark Plug Resistance Measure spark plug resistance. If resistance reading is 2000-20,000 ohms, proceed as follows: If directed here from TROUBLE SHOOTING - NO CODES article, return to «SYMPTOM DIAGNOSIS»(ref-134968-S36579230062002022100000) in TROUBLE SHOOTING - NO CODES article. All others, go to «INTERMITTENT»(ref-150940-S23445146842002120200000) testing. If resistance reading is not as specified, replace faulty spark plug. Complete «FUEL OR MISFIRE MONITOR REPAIR VERIFICATION DRIVE CYCLE»(ref-150940-S00750885652002112700000) under MONITOR REPAIR VERIFICATION DRIVE CYCLES.