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Trouble Code Identification

NOTE: Trouble codes retrieved from PCM may be either engine or transmission related. Only engine related DTCs are covered in this article. For transmission related DTCs, see appropriate AUTO TRANS DIAGNOSIS article, AUTO TRANS DIAGNOSIS - 4L60-E or AUTO TRANS DIAGNOSIS - 4L80-E - GAS in the AUTO TRANS DIAGNOSIS section for domestic vehicles. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION  table to determine if DTC is engine or transmission related.
  1. The DTCs indicate failure of a specific sensor and/or circuit. Sensor/circuit diagnosis may indicate replacement of PCM.
  2. If PCM is replaced at any point during diagnostic testing and if condition is still not corrected after replacing PCM, the following may be the cause:
    • An incorrect PCM may cause a malfunction, which may or may not set a DTC.
    • The PCM connector may be the problem. Connector terminals may have to be removed from connector to be properly checked.
    • Replacement PCM may be faulty.
    • Intermittent problem. Make a careful physical inspection of affected sensor/circuit.
    • A shorted solenoid, coil relay, or harness may be the cause of PCM failure. Use Short Circuit Tester (J-34636) to check for short circuits.
DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

Code Probable Cause
P0101  MAF System Performance
P0102  MAF Sensor Circuit Low Frequency
P0103  MAF Sensor Circuit High Frequency
P0112  IAT Sensor Circuit Low Voltage
P0113  IAT Sensor Circuit High Voltage
P0117  ECT Sensor Circuit Low Voltage
P0118  ECT Sensor Circuit High Voltage
P0121  APP Sensor 1 Circuit Performance
P0122  APP Sensor 1 Circuit Low Voltage
P0123  APP Sensor 1 Circuit High Voltage
P0126  Insufficient ECT For Stable Operation
P0182  Fuel Temperature Sensor Circuit Low Voltage
P0183  Fuel Temperature Sensor Circuit High Voltage
P0215  Engine Shutoff Solenoid Control Circuit
P0216  Injection Timing Control System
P0219  Engine Overspeed Condition
P0220  APP Sensor 2 Circuit
P0221  APP Sensor 2 Circuit Performance
P0222  APP Sensor 2 Circuit Low Voltage
P0223  APP Sensor 2 Circuit High Voltage
P0225  APP Sensor 3 Circuit
P0226  APP Sensor 3 Circuit Performance
P0227  APP Sensor 3 Circuit Low Voltage
P0228  APP Sensor 3 Circuit High Voltage
P0231  Fuel/Lift Pump Feedback Circuit Low Voltage
P0236  Turbocharger Boost System
P0237  Turbocharger Boost Sensor Circuit Low Voltage
P0238  Turbocharger Boost Sensor Circuit High Voltage
P0251  Injection Pump Cam System
P0263  Cylinder No. 1 Balance System
P0266  Cylinder No. 2 Balance System
P0269  Cylinder No. 3 Balance System
P0272  Cylinder No. 4 Balance System
P0275  Cylinder No. 5 Balance System
P0278  Cylinder No. 6 Balance System
P0281  Cylinder No. 7 Balance System
P0284  Cylinder No. 8 Balance System
P0300  Engine Misfire Detected
P0301  Cylinder No. 1 Misfire Detected
P0302  Cylinder No. 2 Misfire Detected
P0303  Cylinder No. 3 Misfire Detected
P0304  Cylinder No. 4 Misfire Detected
P0305  Cylinder No. 5 Misfire Detected
P0306  Cylinder No. 6 Misfire Detected
P0307  Cylinder No. 7 Misfire Detected
P0308  Cylinder No. 8 Misfire Detected
P0335  CKP Sensor Circuit Performance
P0370  Timing Reference High Resolution
P0380  Glow Plug Circuit Performance
P0400  EGR Flow Malfunction
P0401  EGR Flow Insufficient
P0402  EGR Flow Excessive
P0404  EGR Flow Performance
P0405  EGR Sensor Circuit Low Voltage
P0406  EGR Sensor Circuit High Voltage
P0501  Vehicle Speed Sensor Circuit
P0567  Cruise Resume Circuit
P0568  Cruise Set Circuit
P0571  Cruise Brake Switch Circuit
P0601  PCM Memory
P0602  PCM Not Programmed
P0604  Control Module Random Access Memory
P0606  PCM Internal Communication Interrupted
P1125  APP System
P1191  Intake Air Duct Leak
P1214  Injection Pump Timing Offset Error
P1216  Fuel Solenoid Response Time Too Short
P1217  Fuel Solenoid Response Time Too Long
P1218  Injection Pump Calibration Circuit
P1406  EGR Valve Position
P1409  EGR Vacuum System Leak
P1626  VTD Controller Serial Data Circuit
P1621  EEPROM Write
P1627  A/D Performance
P1630  Theft Deterrent PCM In Learn Mode
P1631  Theft Deterrent Password Incorrect
P1635  PCM 5-Volt Reference Low
P1641  MIL Control Circuit
P1643  WAIT TO START Light Control Circuit
P1653  EGR Vent Sol. Control Circuit
P1654  SERVICE THROTTLE SOON Light Control Circuit
P1655  EGR Solenoid Control Circuit
P1656  Wastegate Solenoid Control Circuit