Malfunction Indicator Lamp: Description and Operation

SERVICE ENGINE SOON/MALFUNCTION INDICATOR LAMP (MIL)

The Service Engine Soon/Malfunction Indicator Lamp (MIL) is located in the Instrument Panel Cluster (IPC). The MIL is controlled by the PCM and is used to indicate that the PCM has detected a problem that affects vehicle emissions, may cause powertrain damage, or severely impacts driveability.

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.