Malfunction Indicator (Check Engine) Lamp

Check Engine Lamp:

DESCRIPTION
The malfunction indicator lamp (formerly referred to as the check engine lamp) illuminates on the instrument panel each time the ignition key is turned on. It will stay on for about three seconds as a bulb test.

OPERATION
If the Powertrain Control Module (PCM) receives an incorrect signal, or no signal from certain sensors or components, the lamp is turned on. This is a warning that the PCM has recorded a system or sensor malfunction. It signals an immediate need for service.

The lamp can also be used to display a diagnostic trouble code (DTC). Cycle the ignition switch On-Off-On-Off-On within three seconds and any codes stored in the PCM memory will be displayed. This is done in a series of flashes representing digits.