Malfunction Indicator Lamp (MIL) - Description
SERVICE VEHICLEThe service vehicle indicator is controlled by the following components:
^ The powertrain control module (PCM)
^ The instrument cluster
The PCM sends a Class 2 message through circuit 1036 to the instrument cluster in order to turn on the indicator when problems with the engine have been detected.
The instrument cluster turns on the service soon indicator under the following conditions:
^ Class 2 communication has been lost between the instrument cluster and any other module (PCM, SDM, EBCM).
^ The air bag indicator is defective. DTC B0670 is set.
^ The 3 second bulb test is occurring.
The SERVICE VEHICLE warning light comes on for a 3 second bulb check when the vehicle is first started. This light will stay on steady if there are certain non-emission related vehicle problems. These problems may not be obvious and may affect vehicle performance or durability.
For diagnosis, refer to Computers and Control Systems.
SERVICE ENGINE SOON
The SERVICE ENGINE SOON indicator lamp in the instrument cluster will come on when turning the ignition ON or OFF. This serves as a bulb and system check. The light should go off after the engine starts unless a problem has been detected by the system.
For diagnosis, refer to Computers and Control Systems.