ABS Indicator Inoperative
Circuit Description
The Electronic Brake Control Module (EBCM) controls the operation of the amber ABS indicator lamp by means of a lamp driver module. When the ignition switch is turned to the ON position, the EBCM turns ON the ABS indicator for 3 seconds for a bulb check. Whenever a malfunction is detected within the ABS system, the EBCM funs ON the ABS indicator, notifying the driver that ABS needs to be serviced.
Diagnostic Aids
The following conditions may cause an intermittent malfunction:
^ A poor connection
^ Rubbed-through wire insulation
^ A broken wire inside the insulation
Thoroughly inspect any circuitry that may cause the intermittent complaint for the following conditions:
^ Backed out terminals
^ Improper mating
^ Broken locks
^ Improperly formed or damaged terminals
^ Poor terminal-to-wiring connections
^ Physical damage to the wiring harness
^ Open IG Fuse
^ Open bulb filament
^ Open or poor G200
^ Short to ground in the lamp driver module control circuit
^ Open within l/P gage printed circuit
^ Malfunctioning lamp driver module
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
1. The Diagnostic System Check must be the starting point for any ABS related diagnosis.
2. Tests for power distribution to the instrument panel gage cluster and EBCM.
4. Tests the ABS Indicator Control and the Battery Positive Voltage circuits for a short to ground.
7. Ensures the fault is not in the Lamp Driver Module.