C1249

DTC C1249

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptor
DTC C1249
- Stop Lamp Switch Circuit Open

Circuit/System 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 C1249 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 ABS warning indicator turns ON.
* The ABS is disabled.
* The vehicle stability control (VSC) warning indicator turns ON.
* The VSC is disabled.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

Reference Information
Schematic Reference

Antilock Brake System Schematics ([1][2]Antilock Brakes / Traction Control Systems)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

ABS Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Verify the brake lamps operate.

If brake lamps do not operate, refer to appropriate diagnosis.

Circuit/System Testing

1. Ignition OFF, disconnect the EBCM connector.
2. Ignition ON, check for 8-14V between EBCM connector terminal 2 and ground with brake pedal applied and less than 1.5V with braked pedal released.

• If the voltage is not as specified, test the circuit for a short to ground or an open/high resistance.

3. Ignition ON, check for 11-14V between terminals, 12, 24, 34 and ground.

• If the voltage is not as specified, test the B+ circuit for a short to ground or an open/high resistance.

4. Test for less than 1 ohm between the terminals 1, 13 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the BPMV/EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Brake Pressure Modulator Valve Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for EBCM replacement, setup, and programming