Circuit Description
The stop lamp switch signal informs the electronic brake control module (EBCM) when the brake pedal is pressed.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC C1294 Brake Lamp Switch Circuit Always Active
Conditions for Running the DTC
The vehicle speed is greater than 40 km/h (25 mph).
Conditions for Setting the DTC
The stop lamp switch input was active for 2 consecutive ignition cycles.
Action Taken When the DTC Sets
| • | The EBCM disables the Traction Control System (TCS) for the duration of the ignition cycle. |
| • | The Traction Off indicator turns ON. |
| • | The message center displays the Service Traction System message. |
| • | The Antilock Brake System (ABS) remains functional. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
Possible causes of this DTC are the following conditions:
| • | The stop lamp switch circuit is shorted to voltage. |
| • | The stop lamp switch is misadjusted. |
| • | The stop lamp switch is stuck closed. |
| • | A brake pedal that is binding. |
| • | Both brake light bulbs are burned out. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views or Lighting Systems Connector End Views in Lighting Systems | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Does the scan tool display Released? | Go to Step 3 | Go to Step 4 | |
3 |
Does the Brake Switch Status parameter change state? | Go to Diagnostic Aids | Go to Step 4 |
4 |
Did you find and correct the condition? | Go to Step 11 | Go to Step 5 |
5 |
Does the scan tool display Released? | Go to Step 8 | Go to Step 6 |
6 | Test the stop lamp switch signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 7 |
7 | Inspect for poor connections at the harness connector of the electronic brake control module (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 11 | Go to Step 9 |
8 | Inspect for poor connections at the harness connector of the stop lamp switch. 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 11 | Go to Step 10 |
9 | Replace the EBCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the repair? | Go to Step 11 | -- |
10 | Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Lighting Systems. Did you complete the repair? | Go to Step 11 | -- |
11 |
Does the DTC reset? | Go to Step 2 | System OK |
