Malfunction Indicator Lamp (MIL), Significance

Malfunction Indicator Lamp (MIL), Significance

The Malfunction Indicator Lamp (MIL) lights up when malfunctions are recognized by the Engine Control Module (ECM).

NOTE:
The Malfunction Indicator Lamp (MIL) can blink or be lit continuously. DTC memory should be checked in both cases.
- Blinking: There is a malfunction that damages the catalytic converter in this driving condition. In this case, vehicle must only be driven at reduced power!
- Continuously lit: There is a malfunction that causes increased emissions. Check DTC memory for Motronic ECM or automatic transmission.
- DTC memory must still be checked if there are driveability problems or the customer has made a complaint but the MIL is not lit, because malfunctions can be stored without causing the MIL to light immediately.