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ABS Active Indicator Always On



ABS Active Indicator Always On

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 antilock brake system (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 in Diagnostic Aids. Testing and Inspection
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 indicator lamps on the instrument cluster.
4. Verify if the circuits going to the instrument cluster or the cluster is at fault.