Circuit Description
The electronic brake control module (EBCM) monitors brake pedal position through the stop lamp switch. The stop lamp switch is closed when the brake pedal is pressed and the stop lamp switch opens when the brake pedal is released. When the stop lamp switch is closed, the EBCM receives a voltage signal from the stop lamp switch. The stop lamp switch receives power from the STOP fuse.
Conditions for Running the DTC
DTC 67 can be set anytime.
Conditions for Setting the DTC
The EBCM detects an open in the stop lamp switch circuit.
Action Taken When the DTC Sets
| • | The EBCM disables the traction control system for the remainder of the ignition cycle. |
| • | The TRAC OFF warning indicator turns ON. |
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Diagnostic Aids
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
| • | An open STOP fuse, possible short to ground in its circuitry |
| • | Misadjusted stop lamp switch |
| • | Faulty stop lamp switch |
| • | Open or high resistance in the stop lamp switch input circuit |
| • | An internal EBCM malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
This step inspects the operation of the stop lamps.
-
This step test the EBCM stop lamp circuit for an open or high resistance.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | |||
1 | Did you perform A Diagnostic System Check - ABS? | Go to Step 2 | |
2 | Is DTC 67 set as a current DTC? | Go to Step 3 | Go to Diagnostic Aids |
Press the brake pedal while observing the stop lamp operation. Do the stop lamps operate? | Go to Step 4 | Go to Stop Lamps Inoperative in Lighting Systems | |
Test the EBCM stop lamp circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 5 | |
5 | Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 6 |
6 | Replace the electronic brake control module (EBCM). Refer to Electronic Brake Control Module Replacement . Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |
