Malfunction Indicator Lamp (MIL)

Description and Operation 1-59

Malfunction Indicator Lamp (MIL)

Malfunction Indicator Lamp (MIL)

The MIL notifies the driver the PCM has confirmed an on board diagnostic (OBD) emission related component or system concern. When this occurs, an OBD DTC sets.

• The MIL is located in the instrument panel cluster (IPC) and is labeled CHECK ENGINE, SERVICE ENGINE SOON or the international

standards organization (ISO) standard engine symbol.

• The MIL is illuminated with the ignition ON, engine OFF, until the engine is cranked for starting. The MIL will turn OFF after engine start if

no concerns are present.

• The MIL may flash after 17 seconds with the ignition ON, engine OFF, unless the OBD inspection/maintenance (I/M) readiness indicators

indicate all of the OBD monitors have completed since the last keep alive memory (KAM) reset or since the PCM DTCs have been cleared with a reset command from the scan tool.

• The MIL will remain illuminated after engine start if a confirmed emission related concern or an OBD DTC exists.

• If the MIL flashes at a steady rate, after engine start, a severe misfire condition may exist.

• The MIL will remain OFF with the ignition ON, engine OFF, if a MIL indicator or IPC concern is present.

• To turn OFF the MIL after a repair, a reset command from the scan tool must be sent, or 3 consecutive drive cycles must be completed

without a concern.

• If the MIL flashes erratically, a low battery voltage concern may be present causing the PCM to reset during cranking.

• For all MIL concerns, go to Section 3, Symptom Charts.

CHECK ENGINE, SERVICE ENGINE SOON, Or ISO Standard Engine Symbol

2016 Powertrain Control/Emissions Diagnosis, Gasoline Engines, 3/2015