Malfunction Indicator Lamp (MIL), Function

Malfunction Indicator Lamp (MIL), Function

If emissions-influencing malfunctions are recognized by the TCM, the Malfunction Indicator Lamp (MIL) will be switched on.







Location of the MIL


NOTE:
When the MIL is switched on, it will either blink or light continuously. In either case, the DTC memory for the TCM must be checked.
- MIL flashing: there is a malfunction that could damage the Three Way Catalytic Converter (TWC). In this case, drive only with reduced power.
- MIL continuously on: there is a malfunction that degrades emissions. Check DTC memory for the Engine Control Module (ECM) and the TCM.
- If there are driveability problems (e.g. a customer complaint) and the MIL is not on, the MIL functional test must be carried out, since malfunctions that do not immediately switch on the MIL can be stored.


MIL functional check
- Switch ignition on.
The MIL must light up.

If the MIL lights up when the ignition is switched on (with the engine not running):
- Check DTC memory.
- If necessary, check wiring per wiring diagram or replace light bulb.
- Start engine and let idle.

The MIL must be switched off after several seconds.

If the MIL is not switched off after the engine is started:
- Check DTC memory.

Conditions for recognition of a driving cycle (Dcy)
A driving cycle (Dcy) is considered complete when the ignition is switched on one time, the engine is started, the engine start is recognized by the control module, and the ignition is switched off again.