C0277
DTC C0277, C0278, or C0283
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC C0277
- Brake Pedal Position Sensor Circuit
DTC C0278
- Brake Pedal Position Sensor Not Calibrated
DTC C0283
- Brake Pedal Position Sensor Circuit Low
Diagnostic Fault Information
Circuit/System Description
The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal that will increase as the brake pedal is applied. The body control module (BCM) provides a low reference signal and a 10-volt reference voltage to the brake pedal position sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM will apply battery voltage to the stop lamps, transmission control module (TCM), engine control module (ECM), electronic brake control module (EBCM), and center high mounted stop lamp (CHMSL).
Conditions for Running the DTC
* Battery voltage must be between 9-16 volts.
* Brakes APPLIED.
Conditions for Setting the DTC
DTC C0277 will set for the following conditions:
* The BCM detects a short to voltage or an open/high resistance in the brake pedal position sensor signal circuit.
* The BCM detects a short to ground or an open/high resistance in the brake pedal position sensor 5-volt reference circuit.
* The BCM detects an open/high resistance in the brake pedal position sensor low reference circuit.
DTC C0278 will set when the brake pedal position sensor home position is not learned.
Action Taken When the DTC Sets
* The Service Vehicle Soon indicator is commanded ON.
* When DTC C0277 is set as current, the vehicle will not start.
* If the DTC sets while the vehicle is running, the BCM will activate the brake lights when the vehicles transmission is not in the PARK position and the vehicle is not accelerating.
Conditions for Clearing the DTC
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.
Diagnostic Aids
Important: The stop lamps will not illuminate unless the ignition is in the ON position. For more detailed information concerning stop lamp operation, refer to Exterior Lighting Systems Description and Operation Exterior Lighting Systems.
Reference Information
Schematic Reference
Exterior Lights Schematics Exterior Lights Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Exterior Lighting Systems Description and Operation Exterior Lighting Systems
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Testing
DTC C0277 or C0283
1. Ignition OFF, disconnect the harness connector at the brake pedal position sensor.
2. Ignition OFF, verify that a test lamp illuminates between B+ and the low reference circuit terminal A.
• If the test lamp does not illuminate, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
3. Ignition ON, test for 9.8-10.2 volts between the 10-volt reference circuit terminal A and ground.
• If greater than the specified range, test the 10-volt reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
• If less than the specified range, test the 10-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
4. Verify the scan tool BPP Sensor parameter is less than 4 counts.
• If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the BCM.
5. Install a 3A fused jumper between the signal circuit terminal B and the 10-volt reference circuit terminal A. Verify the scan tool BPP Sensor parameter is greater than 250 counts.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
6. If all circuits test normal, test or replace the brake pedal position sensor.
DTC C0278
1. Verify that the DTC sets under the Conditions for Running and Setting.
2. Perform the brake pedal position sensor recalibration procedure.
3. Operate the vehicle within the conditions that the customer experienced and verify the DTC does not reset.
• If the DTC resets, replace the brake pedal position sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Brake Pedal Position Sensor Calibration Testing and Inspection
* Brake Pedal Position Sensor Replacement Service and Repair
* Control Module References Control Module References for BCM replacement, setup, and programming