Malfunction Indicator Lamp: Description and Operation

MALFUNCTION INDICATOR LAMP (MIL)

The MIL informs the driver that the powertrain control module (PCM) has detected an OBD emission-related component or system concern. When this occurs on a California-calibrated engine, an OBD diagnostic trouble code (DTC) is set. On a federal calibrated engine and transmission, certain concerns also illuminate the MIL.
- The MIL is located in the instrument cluster.
- The indicator is illuminated by a PCM message sent through the controller area network (CAN) to the instrument cluster.
- An engine or transmission with federal calibration operating in the failure mode effects management (FMEM) may cause the MIL to be illuminated.
- To turn off the MIL after a repair, a clear DTCs command from the scan tool must be sent to the PCM.
- For any MIL concern, go to Symptom Charts, Powertrain Control Module (PCM) Quick Test. QT: Powertrain Control Module (PCM) Quick Test

Malfunction Indicator Lamp (MIL):