Malfunction Indicator Lamp: Description and Operation

PURPOSE
Inform operator of system malfunction detected by on-board diagnostic system. Provides method for reading codes.

OPERATION
As a self-test, malfunction indicator lamp (MIL) lights for approximately 3 seconds when ignition is turned "ON," then goes out. If a monitored device malfunction is detected, malfunction indicator lamp (MIL) will stay "ON" with the engine running. When data link connector is jumped between terminals "TEN" and "GND," MIL flashes codes corresponding to defective input/output devices and/or their circuits. If more than one failure present, lowest number code is displayed first, followed by remaining codes in numerical order.