On-Board Diagnostics

ON-BOARD DIAGNOSTICS
- Diagnostic trouble codes are set as follows:
After the PCM first detects a malfunction, a diagnostic trouble code is recorded when the engine is restarted and the same malfunction is re-detected. (The malfunction is detected in driving cycle). However, for fuel system rich/lean misfiring, a diagnostic trouble code is recorded on the first detection of the malfunction.

- Erasing diagnostic trouble codes:
After recording the diagnostic trouble code, if the PCM does not re-detect the malfunction for 40 driving cycles, the diagnostic trouble code will be erased from the PCM memory However, for fuel system rich/lean or misfiring, the diagnostic trouble code will be erased if both of the following conditions are met:
- When driving conditions (engine speed, engine coolant temperature, etc.) are identical to those when the malfunction was first recorded.
- When the PCM does not re-detect the malfunction for 80 driving cycles.

NOTE: A "driving cycle" is complete as soon as the vehicle goes into closed loop operation.