Malfunction Indicator Lamp (MIL) Significance

If malfunctions are recognized by the Engine Control Module (ECM), the ECM will switch ON the MIL lamp.





Location of Malfunction Indicator Lamp


NOTE: The MIL lamp can be switched ON in the flashing or permanently ON mode, however; DTC memory must be checked in either case. Refer to Computers and Controls, System Diagnosis, "How to Display and Read Diagnostic Codes" at "On Board Diagnostic (OBD II)".

- Flashing: There is a malfunction which can cause damage to the Three-Way Catalyst if driven in this condition. With this condition the vehicle must not be driven under full load.
- Permanently ON: There is a malfunction which will increase exhaust emission. Check the Engine Control Module (ECM) and the Transmission Control Module (TCM).
- If the MIL lamp does not light up, even though there is an engine running problem, or a customer complaint, DTC memory must be checked, because malfunctions which do not switch ON the MIL lamp immediately can also be stored.

Functional check:
- Switch ON ignition
- MIL lamp must light up

If MIL lamp does not light-up with ignition switched ON
- Check wiring between the ECM and MIL lamp as follows:






If the MIL lamp lights-up with ignition switched ON, continue check as follows:
- Start engine and let idle
- MIL lamp must go out after a few seconds

If MIL lamp does not go out
- Check DTC memory. Refer to Computers and Controls, System Diagnosis, "How to Display and Read Diagnostic Codes" at "On Board Diagnostic (OBD II)".

If no DTC code stored:
- Refer to chart