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ABS Indicator Inoperative



ABS Indicator Inoperative

Circuit Description

The instrument panel cluster (IPC) turns the ABS indicator on during the IPC bulb check for approximately 3 seconds when the ignition switch is turned to the ON position. If the electronic brake control module (EBCM) sets a diagnostic trouble code (DTC) the EBCM sends a class 2 message to the body control module (BCM) and the BCM sends a class 2 message to the IPC to command the ABS indicator on.

Diagnostic Aids

* It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
* Thoroughly inspect any circuitry that may be causing the 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
* The following conditions may cause an intermittent malfunction:
^ A poor connection
^ Rubbed-through wire insulation
^ A broken wire inside the insulation
* If an intermittent malfunction exists Refer to Inducing Intermittent Fault Conditions.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2. Confirm if the scan tool can turn on and off all the indicator lamps in the instrument cluster.
4. Verify if the circuits going to the instrument cluster or the cluster is at fault.

Step 1 - Step 4: