Malfunction Indicator Lamp: Testing and Inspection

MIL VERIFICATION

Typical Fault Indicator Light:

To verify that the vehicle is equipped with a functional malfunction indicator lamp turn the ignition switch "ON", and observe dash lights. A "CHECK" light with an engine symbol should illuminate (malfunction indicator lamp).

Data Link Connectors V8:

DLC Terminal Identification:

If no malfunction indicator lamp is showing, leave the ignition switch turned "ON", locate the Data Link Connectors (DLC) in the passengers footwell area (below the auxiliary relay panel). Bridge the lower terminals of connectors 1 and 2 as shown using suitable jumper wire.

If the vehicle is equipped with a functional malfunction indicator lamp, the lamp will light up while data link connectors are properly bridged and provided the lamp is not burned out. If the lamp did not light when the ignition was turned ON, but did light with the data link connectors bridged, then there may be a problem with the ECM lamp driver circuit, ECM terminal connection/wiring, or the ECM itself. Before suspecting a bad ECM, or if at this point no malfunction indicator lamp has shown, use of an LED test light at the data link connectors will be necessary to extract the diagnostic trouble codes.