The stop lamp switch signal informs the electronic brake control module (EBCM) when the brake pedal is pressed.
This diagnostic procedure supports the following DTC:
DTC C0281 Stop Lamp Switch Circuit
Either of the following conditions will cause the DTC to run:
• | The ignition is ON and the vehicle achieves at least 56 km/h (35 mph) before coming to a stop. |
• | The ignition is ON and the vehicle experiences an antilock brake system (ABS) event lasting at least 1 second. |
The EBCM detects an open or shorted brake switch or brake switch circuit.
This information-only DTC is stored in EBCM memory until it is cleared by using the specified procedure.
The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to the following:
The numbers below refer to the step numbers 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 |
2 |
Does the scan tool display Off? | Go to Step 3 | Go to Step 5 |
3 |
Does the scan tool display On? | Go to Diagnostic Aids | Go to Step 4 |
Does the scan tool display On? | Go to Step 9 | Go to Step 7 | |
Does the scan tool display Off? | Go to Step 9 | Go to Step 6 | |
6 | Test the ignition 3 voltage circuit and the TCC brake switch signal circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 8 |
7 | Test the TCC brake 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 12 | Go to Step 8 |
8 | 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 12 | Go to Step 10 |
9 | 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 12 | Go to Step 11 |
10 | Replace the EBCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 12 | -- |
11 | Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Lighting Systems. Did you complete the replacement? | Go to Step 12 | -- |
12 |
Does the DTC reset? | Go to Step 2 | System OK |