Entering Diagnostic Mode
- Turn ignition on. "CHECK ENGINE" light should glow. Locate diagnostic leads. See Fig 1 . Connect diagnostic terminal leads together. If any trouble codes are stored in ECU memory, the "CHECK ENGINE" light will flash 2-digit codes.
- The trouble codes will be displayed from lowest to highest numbered code. Each code is repeated three times before the next code sequence is displayed. The trouble codes will be repeated as long as the diagnostic terminals are connected and the ignition is on.
NOTE:
An example of trouble codes is as follows: "FLASH", "FLASH", pause, "FLASH", "FLASH", "FLASH" followed by a longer pause identifies trouble code 23. First series of flashes indicates first digit of trouble code. Second series of flashes indicates second digit of trouble code.
ECU TROUBLE CODE IDENTIFICATION
| Code | Problem |
|---|---|
| 12 | No Ignition - Normal condition |
| 13 | Open Oxygen Sensor Circuit |
| 14 | Shorted Coolant Sensor Circuit |
| 15 | Incorrect Coolant Sensor Circuit |
| 16 | Open Coolant Sensor Circuit |
| 21 | Throttle Position Switch Circuits Connected at Same Time |
| 22 | Starter Signal Circuit |
| 23 | Output Terminal to Ignition Coil Grounded |
| 25 | Output Terminal to Vacuum Switching Solenoid Circuit Open or Grounded |
| 33 | Open or Shorted Fuel Injector Circuit |
| 35 | Ignition Power Transistor Open |
| 41 | Bad Signal From Crank Angle Sensor |
| 43 | No Idle Position Signal |
| 44 | Lean Oxygen Sensor Indication |
| 45 | Rich System Indication |
| 51 | Faulty ECU |
| 52 | Faulty ECU |
| 53 | Vacuum Switching Valve |
| 54 | Bad Ignition Transistor or Ground |
| 55 | Faulty ECU |
| 61 | Circuit to Airflow Sensor Bad |
| 62 | Circuit to Airflow Sensor Bad |
| 63 | No Vehicle Speed Sensor Signal |
| 64 | Fuel Injector Transistor or Ground |
| 65 | Continuous Signal From Throttle Position Switch |
| 66 | Open or Shorted Knock Sensor Circuit |
| 71 | Abnormal Signal from TPS |
| 72 | Output Terminal to EGR Vacuum Switching Valve Open or Grounded |
| 73 | EGR Vacuum Switching Valve or Ground |