Check Engine Indicator Lamp

CHECK ENGINE indicator lamp

Schematic:

The CHECK ENGINE lamp (MIL) warns the driver when a fault occurs in the engine management system.

The lamp is powered by the main instrument unit and is grounded internally by the main instrument unit. The engine control module sends continuous bus information CHECK ENGINE, unit ON/OFF.

On receiving CHECK ENGINE ON, the control module grounds the output of the lamp, which then lights up.

On certain markets, TCM (Transmission Control Module) will turn on the CHECK ENGINE lamp.

If the engine control module changes the status of the message to CHECK ENGINE OFF, the lamp will go out.

The lamp will stay on until the engine is started if the ignition is turned to ON. Provided there are no faults, the engine control module will send bus information CHECK ENGINE OFF and the lamp will go out.

Diagnostics
The function has no diagnostics.