ECM Trouble Code Definitions
ECM TROUBLE CODE DEFINITION
| Code No. | Circuit Affected |
|---|---|
| 13 | Open oxygen sensor circuit |
| 14 | Coolant sensor circuit shorted |
| 15 | Coolant sensor circuit open |
| 21 | TPS signal voltage high |
| 22 | TPS signal voltage low |
| 23 | MAT voltage high |
| 24 | VSS circuit |
| 25 | MAT sensor signal voltage low |
| 32 | EGR vacuum control signal |
| 33 | MAT sensor voltage high |
| 34 | MAT sensor voltage low |
| 36 | MAF Burn-Off Failure |
| 41 | No distributor reference (HEI) |
| 41 | C(3)I ignition - cam sensor loss |
| 41 | Cylinder select error (MEM-CAL) |
| 42 | EST circuit open or grounded |
| 43 | ESC retard signal too low |
| 44 | Lean oxygen sensor value |
| 45 | Rich oxygen sensor value |
| 46 | Vehicle Anti-Theft System (VATS) |
| 53 | Faulty alternator, voltage high |
| 54 | Fuel pump voltage low |
| 55 | Faulty ECM |
NOTE:
Trouble code charts should only be used if "SERVICE ENGINE SOON" light is illuminated (indicating a current problem exists). Exceptions are Code 13, 15, 24, 44 and 45 charts, which may be used to help diagnose intermittent codes.
NOTE:
Any time Codes 51, 52, 54 or 55 are displayed with another code, start with "50-series" code first, then proceed to low profile numbered code.