Table of ContentsNOTE: 96 & later are OBD2 systems and require a scanner. For an OBD2 code list, please see our GM code list or the appropriate generic list.
GM Import Codes by Model
87-88
Sprint Turbo,89 & later Metro, Tracker, Storm. |
|---|
| 12 | Diagnostic function working |
| 13 | Oxygen sensor or circuit |
| 14 | Coolant temperature sensor or circuit (open) |
| 15 | Coolant temperature sensor or circuit (shorted) |
| 21 | Throttle position sensor or circuit (open) |
| 22 | Throttle position sensor or circuit (shorted) |
| 23 | Intake air temperature sensor or circuit (open) |
| 24 | Vehicle speed sensor (VSS) or circuit |
| 25 | Intake air temperature sensor or circuit (shorted) |
| 31 | High turbo pressure (87 – 88) |
| 31 | Barometric pressure sensor or circuit (89 -95) |
| 32 | Barometric pressure sensor or circuit (89 – 95) |
| 32 | EGR system (91 – 93) |
| 33 | Airflow meter (turbo) |
| 33 | Manifold Absolute Pressure (MAP) sensor (90 – 91) |
| 41 | Ignition signal problem |
| 42 | Crank angle sensor (except Storm) |
| 42 | Camshaft position sensor circuit (94-95) |
| 42 | Electronic Spark Timing (EST) (Storm) |
| 44 | ECM idle switch circuit open |
| 44 | Oxygen sensor or circuit – lean exhaust |
| 45 | Oxygen sensor or circuit – rich exhaust |
| 46 | Idle speed control motor |
| 51 | EGR system (except Storm) |
| 51 | ECM (Storm) |
| 53 | ECM ground circuit |
| ON Steady | ECM faulty |
89 – 92 GEO Metro TBI |
|---|
| 13 | Oxygen Sensor circuit. |
| 14 | Coolant Temperature Sensor circuit. High temperature indicated. |
| 15 | Coolant Temperature Sensor circuit. Low temperature indicated. |
| 21 | Throttle Switch circuit (Manual Transmission). |
| 21 | Throttle Position Sensor Signal Voltage High (Automatic Transmission). |
| 22 | Throttle Position Sensor Signal Voltage Low. |
| 23 | Intake Air temperature (MAT) Sensor. Low temperature indicated. |
| 24 | Vehicle Speed Sensor circuit. |
| 25 | Intake Air temperature (MAT) Sensor. High temperature indicated. |
| 31 | MAP Sensor circuit – Signal Voltage Low Vacuum. |
| 32 | MAP Sensor circuit – Signal Voltage High Vacuum. |
| 33 | MAP Sensor circuit. |
| 41 | Ignition Signal circuit. |
| 42 | Crank Angle Sensor. |
| 46 | Idle Speed Control Motor circuit. |
| 51 | EGR circuit. |
| 53 | Ground circuit. |
| 93 – 95 |
|---|
| 13 | Oxygen Sensor circuit. Signal voltage does not change. |
| 14 | Engine Coolant Temperature Sensor circuit High Voltage Input. Low temperature
indicated. |
| 15 | Engine Coolant Temperature Sensor circuit Low Voltage Input. High temperature
indicated. |
| 21 | Throttle Position Sensor circuit High Voltage Input. |
| 22 | Throttle Position Sensor circuit Low Voltage Input. |
| 23 | Intake Air temperature Sensor circuit – High Voltage Input. Low temperature
indicated. |
| 24 | Vehicle Speed Sensor circuit. |
| 25 | Intake Air temperature Sensor circuit – Low Voltage Input. High temperature
indicated. |
| 31 | MAP Sensor circuit Low Voltage Input – Low manifold pressure. |
| 32 | MAP Sensor circuit High Voltage Input – High manifold pressure. |
| 41 | Ignition Signal circuit. |
| 42 | Crankshaft Position Sensor circuit – No Signal for 2 seconds. |
| 46 | Idle Speed Control Motor circuit. |
| 51 | EGR circuit. |
Sprint(non-turbo) |
|---|
| 12 | Diagnostic function working |
| 13 | Oxygen sensor circuit |
| 14 | Coolant temperature sensor circuit |
| 21 | Throttle position switches or circuit |
| 23 | Intake air temperature circuit |
| 32 | Barometric Pressure circuit |
| 51 | Possible faulty ECM |
| 52 | Fuel cut solenoid or circuit |
| 53 | Secondary air circuit |
| 54 | Mixture control solenoid or circuit |
| 55 | Bowl vent solenoid or circuit |
GEO,
Sprint, Nova & Spectrum |
|---|
| 12 | No distributor reference pulse to ECM |
| 13 | Oxygen sensor circuit |
| 14 | Coolant sensor – high or low temp |
| 21 | Throttle Position Sensor (TPS) voltage high or low |
| 23 | Intake Air Temperature IAT sensor circuit voltage high or low |
| 24 | Vehicle Speed Sensor (VSS) or circuit |
| 32 | EGR (Exhaust gas recirculation) EVRV shorted to ground on start-up |
| 33 | Manifold Absolute Pressure (MAP) sensor voltage high or low |
| 42 | Electronic Spark Timing (EST) circuit |
| 43 | Detonation (knock) sensor or circuit–Turbo type |
| 44 | Oxygen sensor or circuit indicates lean exhaust (heated type) |
| 45 | Oxygen sensor or circuit indicates rich exhaust |
| 51 | ECM or EEPROM |
Spectrum |
|---|
| 12 | No distributor reference pulses to ECM |
| 13 | Oxygen sensor circuit |
| 14 | Coolant sensor circuit shorted. |
| 15 | Coolant sensor circuit open. |
| 16 | Coolant sensor circuit open. |
| 21 | Idle switch out of adjustment (or open circuit) non-Turbo t |
| 21 | Throttle Position Sensor (TPS) voltage high– Turbo |
| 22 | Fuel cut off relay or circuit open–non-Turbo |
| 22 | Throttle Position Sensor (TPS) voltage low–Turbo |
| 23 | Open or grounded Mixture Control(M/C) solenoid or circuit–
non-Turbo |
| 23 | Manifold Air Temperature MAT sensor or circuit–Turbo |
| 24 | Vehicle Speed Sensor (VSS) or circuit–Turbo |
| 25 | Open or grounded vacuum switching valve or circuit–non-Turbo |
| 25 | Air Switching Valve (ASV) or circuit–Turbo |
| 31 | Wastegate control–Turbo |
| 33 | Manifold Absolute Pressure (MAP) sensor voltage high–Turbo |
| 34 | Manifold Absolute Pressure (MAP) sensor voltage low–Turbo |
| 42 | Electronic Spark Timing (EST) circuit EST circuit is grounded or open.
Turbo |
| 42 | Fuel cut off relay or circuit non-Turbo type |
| 43 | Detonation (knock) sensor or circuit–Turbo type |
| 44 | Oxygen sensor or circuit indicates lean exhaust non-Turbo |
| 45 | Oxygen sensor or circuit indicates rich exhaust |
| 51 | ECM or PROM |
| 53 | Shorted switching unit or faulty ECM non-Turbo |
| 54 | Mixture Control (M/C) solenoid or circuit, or faulty ECM non-Turbo |
| 55 | Faulty ECM non-Turbo |
