Operation CHARM: Car repair manuals for everyone.

Malfunction Indicator Lamp (MIL)

The PCM illuminates the MIL (service engine soon or check engine) when the following occurs:
- The PCM detects a malfunction in the emissions system.
- The PCM performs the displays test at the start of each ignition cycle. The indicator illuminates for approximately 3 seconds.
- The ignition is on, with the engine off.