C0277
DTC C0277
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 Descriptors
DTC C0277 06
- Brake Pedal Position Sensor Circuit Short to Ground or Open
DTC C0277 07
- Brake Pedal Position Sensor Circuit Voltage Above Threshold
DTC C0277 09
- Brake Pedal Position Sensor Circuit Rate of Change Above Threshold
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 5-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 voltage to the center high mounted stop lamp (CHMSL) relay coil. When the CHMSL relay receives voltage from the BCM, the relay coil is energized and the CHMSL relay switch contacts close applying battery voltage to the CHMSL, transmission control module (TCM), and engine control module (ECM).
Conditions for Running the DTC
* Battery voltage must be between 9-16 volts.
* Brakes APPLIED.
Conditions for Setting the DTC
C0277 06
This DTC will set for the following conditions:
* The BCM detects a short to ground 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.
C0277 07
This DTC will set for the following conditions:
* The BCM detects a short to battery voltage in the brake pedal position sensor signal circuit.
* The BCM detects an open/high resistance in the brake pedal position sensor low reference circuit.
C0277 09
The DTC will set when the BCM detects the brake pedal position sensor signal is changing faster than possible under normal operating conditions.
Actions 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.
* For DTC C0277 07 the ignition must be cycled before the code can be cleared.
* A history DTC will clear once 50 malfunction-free ignition cycles have occurred.
* A DTC will not clear the current status until the next ignition cycle.
Reference Information
Schematic Reference
Exterior Lights Schematics (Exterior Lights Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Exterior Lighting Systems Description and Operation (Exterior Lighting Systems 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 Testing
C0277 06 and C0277 07
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 C.
• 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 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.
• If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
• If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
4. Verify the scan tool BPP Sensor parameter is less than 0.2 volts.
• 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 wire between the signal circuit terminal B and the 5-volt reference circuit terminal A. Verify the scan tool BPP Sensor parameter is greater than 4.75 volts.
• If less than the specified range, test the signal circuit for 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.
C0277 09
1. Replace the brake pedal position sensor.
2. Perform the brake pedal position sensor recalibration procedure. Refer to Brake Pedal Position Sensor Calibration (Programming and Relearning).
3. Operate the vehicle within the Conditions for Running and Setting the DTC and verify the DTC does not reset.
• If the DTC resets, replace the BCM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Brake Pedal Position Sensor Calibration (Programming and Relearning)
* Brake Pedal Position Sensor Replacement (Brake Pedal Position Sensor Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming