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.
Conditions for Setting the DTC
All of the following conditions occur:
| • | The EBCM/EBTCM commands the ABS indicator ON. |
| • | The EBCM/EBTCM detects one of the following conditions in the ABS indicator control circuit: |
| - | An open |
| - | A short to ground |
| - | A short to voltage |
Actions Taken When the DTC Sets
| • | A malfunction DTC is stored. |
| • | The ABS remains functional. |
| • | For a short, the ABS indicator remains OFF. |
| • | For an open, the ABS indicator is turned ON. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present and you used the scan tool Clear DTC function. |
| • | The EBCM/EBTCM does not detect the DTC in 50 drive cycles. |
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.
-
This step checks if CKT 852 (WHT) is shorted to voltage.
-
This step checks if CKT 852 (WHT) is shorted to ground.
-
This step checks for an open in CKT 852 (WHT).
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | |
Is the voltage within the specified range? | Battery Voltage | Go to Step 3 | Go to Step 4 | |
3 | Repair the short to voltage in CKT 852 (WHT). Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | -- | |
Does the resistance equal the specified value? | OL (infinite) | Go to Step 6 | Go to Step 5 | |
5 | Repair the short to ground in CKT 852 (WHT). Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | -- | |
Is the resistance less than the specified value? | 5 ohms | Go to Step 7 | Go to Step 8 | |
7 | Replace the EBCM/EBTCM. Refer to Electronic Brake Control Module Replacement . Did you complete the repair? | -- | -- | |
8 | Repair an open or high resistance in CKT 852 (WHT). Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | -- |
