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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 - 4L80-E - 2 DIGIT CODES or AUTO TRANS DIAGNOSIS - 4L80E(DIESEL) - 4 DIGIT CODE 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 (1) Probable Cause
P0112 (2) IAT Sensor Circuit Low Voltage
P0113 (2) IAT Sensor Circuit High Voltage
P0117 (2) ECT Sensor Circuit Low Voltage
P0118 (2) ECT Sensor Circuit High Voltage
P0121 (2) APP Sensor 1 Circuit Performance
P0122 (2) APP Sensor 1 Circuit Low Voltage
P0123 (2) APP Sensor 1 Circuit High Voltage
P0182 (2) Fuel Temperature Sensor Circuit Low Voltage
P0183 (2) Fuel Temperature Sensor Circuit High Voltage
P0215 (2) Engine Shutoff Solenoid Control Circuit
P0216 (2) Injection Timing Control System
P0219 (2) Engine Overspeed Condition
P0220 (2) APP Sensor 2 Circuit
P0221 (2) APP Sensor 2 Circuit Performance
P0222 (2) APP Sensor 2 Circuit Low Voltage
P0223 (2) APP Sensor 2 Circuit High Voltage
P0225 (2) APP Sensor 3 Circuit
P0226 (2) APP Sensor 3 Circuit Performance
P0227 (2) APP Sensor 3 Circuit Low Voltage
P0228 (2) APP Sensor 3 Circuit High Voltage
P0231 (2) Fuel/Lift Pump Feedback Circuit Low Voltage
P0251 (2) Injection Pump Cam System
P0263 (2) Cylinder No. 1 Balance System
P0266 (2) Cylinder No. 2 Balance System
P0269 (2) Cylinder No. 3 Balance System
P0272 (2) Cylinder No. 4 Balance System
P0275 (2) Cylinder No. 5 Balance System
P0278 (2) Cylinder No. 6 Balance System
P0281 (2) Cylinder No. 7 Balance System
P0284 (2) Cylinder No. 8 Balance System
P0300 (2) Engine Misfire Detected
P0301 (2) Cylinder No. 1 Misfire Detected
P0302 (2) Cylinder No. 2 Misfire Detected
P0303 (2) Cylinder No. 3 Misfire Detected
P0304 (2) Cylinder No. 4 Misfire Detected
P0305 (2) Cylinder No. 5 Misfire Detected
P0306 (2) Cylinder No. 6 Misfire Detected
P0307 (2) Cylinder No. 7 Misfire Detected
P0308 (2) Cylinder No. 8 Misfire Detected
P0335 (2) CKP Sensor Circuit Performance
P0370 (2) Timing Reference High Resolution
P0380 (2) Glow Plug Circuit Performance
P0501 (2) Vehicle Speed Sensor Circuit
P0567 (2) Cruise Resume Circuit
P0568 (2) Cruise Set Circuit
P0571 (2) Cruise Brake Switch Circuit
P0601 (2) PCM Memory
P0602 (2) PCM Not Programmed
P0606 (2) PCM Internal Communication Interrupted
P1125 (2) APP System
P1214 (2) Injection Pump Timing Offset Error
P1216 (2) Fuel Solenoid Response Time Too Short
P1217 (2) Fuel Solenoid Response Time Too Long
P1218 (2) Injection Pump Calibration Circuit
P1621 (2) PCM Memory Performance/EEPROM Write
P1627 (2) A/D Performance
P1635 (2) PCM 5-Volt Reference Low
P1641 (2) MIL Control Circuit
P1654 (2) SERVICE THROTTLE SOON Light Control Circuit
P1656 (2) Wastegate Solenoid Control Circuit
(1) For transmission related codes, see AUTO TRANS DIAGNOSIS article in the AUTO TRANS DIAGNOSIS section for domestic vehicles.
(2) Code is engine related.
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