Circuit Description
The EBCM/EBTCM controls the ABS indicator through the brake lamp driver module. The instrument cluster or remote indicator bank supplies voltage to the ABS indicator. The brake lamp driver module acts as an inverter. When the EBCM/EBTCM supplies a ground to the brake lamp driver module, the indicator remains OFF. When the EBCM/EBTCM removes ground from the brake lamp driver module, the brake lamp driver module supplies ground to the ABS indicator.
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. |
| • | An intermittent malfunction can be caused by poor connections, broken insulation, or a wire that is broken inside the insulation. |
| • | If an intermittent malfunction exists, refer to Intermittents and Poor Connections Diagnosis in Wiring Systems. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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This step inspects in order to see if the EBCM/EBTCM is not cable of supplying the ground.
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This step checks for a short to ground in CKT 875 (LT GRN/BLK).
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | |
Does the ABS indicator turn off? | -- | Go to Step 3 | Go to Step 4 | |
3 | Replace the EBCM/EBTCM. Refer to Electronic Brake Control Module Replacement . Did you complete the repair? | -- | -- | |
Is the ABS indicator on? | -- | Go to Step 5 | Go to Step 6 | |
5 | Repair a short to ground in CKT 875 (LT GRN/BLK). Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | -- | |
6 | Replace the brake lamp driver module. Refer to Lamp Driver Module Replacement . Did you complete the repair? | -- | -- |
