TROUBLE CODE IDENTIFICATION
Note. Trouble codes retrieved from PCM/TCM may be related to either engine or transmission. Transmission-related codes are covered in this article. For engine-related codes, see appropriate G - TESTS W/ CODES article. See TROUBLE CODE IDENTIFICATION table to determine if code is transmission or engine related.
- The system codes indicate failure of a specific sensor and/or circuit. Sensor/circuit diagnosis may indicate replacement of the control unit. Code 51 indicates PROM/MEM-CAL is installed improperly or has failed.
- Code 52 indicates PCM/TCM has failed and must be replaced. If the condition is still not corrected after replacing PCM/TCM, the cause may be as follows. An incorrect PCM/TCM or PROM/MEM-CAL application may cause a malfunction, which may or may not set a code. The PCM/TCM connector may be the problem. Connector terminals may have to be removed from the connector to be properly checked. PROM/MEM-CAL failure. Although the PROM/MEM-CAL rarely fails, it could be the cause of the problem. Replacement PCM/TCM 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/TCM failure. Use Short Circuit Tester (J-34636) to check for short circuits.
| Code | Probable Cause |
|---|---|
| 12 (1) | No Engine Speed Sensor Reference Pulse To PCM/TCM |
| 13 (1) | Open Oxygen Sensor Circuit (Gasoline) |
| 14 (1) | CTS Voltage Low (Sensor Or Signal Line Grounded) |
| 15 (1) | CTS Voltage High (Sensor, Connections, Or Wires Open) |
| 21 (1) | TPS Voltage High (Open Circuit Or Misadjusted TPS) |
| 22 (1) | TPS Voltage Low (Circuit Grounded) |
| 23 (1) | TPS Not Calibrated (Diesel - .25-1.3 Volts At Curb Idle) |
| 23 (1) | Intake Air Temperature Sensor Voltage High (Gasoline) |
| 24 (1) | Vehicle Speed Sensor Circuit Open Or Grounded |
| 25 (1) | Intake Air Temperature Sensor Voltage Low (Gasoline) |
| 28 | Pressure Switch Manifold Range Circuit Open Or Shorted |
| 31 (1) | MAP Voltage Low (Diesel) |
| 31 (1) | Turbocharger Wastegate Overboost (Gasoline) |
| 32 (1) | EGR Error (Improper Vacuum Signal) |
| 33 (1) | MAP Voltage High |
| 34 (1) | MAP Voltage Low (Gasoline) |
| 35 (1) | IAC System Fault (Gasoline) |
| 39 | TCC Stuck Off (Faulty TCC Solenoid) |
| 42 (1) | EST Circuit Fault (Gasoline) |
| 43 (1) | ESC Fault (Gasoline) |
| 44 (1) | Lean Exhaust Indicated (Gasoline) |
| 45 (1) | Rich Exhaust Indicated (Gasoline) |
| 51 (1) | Improperly Installed/Faulty PROM/MEM-CAL |
| 52 (1) | PCM/TCM Fault |
| 53 | System Voltage High (Gasoline - Charging Problem) |
| 53 | Voltage Reference Overload (Diesel) |
| 54 (1) | Fuel Pump Circuit Voltage Low (Gasoline) |
| 55 (1) | Faulty ECM (Gasoline) |
| 58 | TTS High Temperature (Sensor Or Signal Line Grounded) |
| 59 | TTS Low Temperature (Sensor, Connections, Or Wires Open) |
| 68 | Overdrive Ratio Error (Engine RPM Greater Than Input Speed) |
| 73 | Force Motor Commanded Amperage Differs From Return |
| 75 | System Voltage Low (Charging System Problem) |
| 81 | QDM Solenoid "B" Monitored Voltage Differs From Commanded |
| 82 | QDM Solenoid "A" Monitored Voltage Differs From Commanded |
| 83 | QDM TCC Monitored Voltage Differs From Commanded |
| 85 | Undefined Gear Ratio (Input Or Output Sensor Failure) |
| 86 | Shift Solenoid "B" Stuck On (Commanded Gear Not Engaged) |
| 87 | Shift Solenoid "B" Stuck Off (Commanded Gear Not Engaged) |
| (1) Code is engine related. For information on engine-related trouble codes, see appropriate G - TESTS W/ CODES article. | |
| (1) | Code is engine related. For information on engine-related trouble codes, see appropriate G - TESTS W/ CODES article. |
TROUBLE CODE IDENTIFICATION