DTC C0277 or C0890

 Diagnostic Instructions


• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions has overviews of all diagnostic categories.
 DTC Descriptors

 DTC C0277 06

Brake Pedal Position Sensor Circuit Low Voltage/Open

 DTC C0277 07

Brake Pedal Position Sensor Circuit High Voltage

 DTC C0277 09

Brake Pedal Position Sensor Circuit Too Fast Transitions

 DTC C0277 4B

Brake Pedal Position Sensor Circuit Calibration Not Learned

 DTC C0890 03

Control Module Voltage Reference Output 3 Circuit Low Voltage

 DTC C0890 07

Control Module Voltage Reference Output 3 Circuit High Voltage

 Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
5V Reference

 C0277 06, C0890 03

 C0277 06

 C0277 07, C0890 07

 -
Signal

 C0277 06, C0890 03

 C0277 06

 C0277 07, C0890 07

 C0277 09
Low Reference

 -

 1

 -

 -
1. Stop Lamps Always ON



 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 provides a low reference signal and a 5 V 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 lamp control circuit and center high mounted stop lamp control circuit. When the control circuit is energized the stop lamps are illuminated.

 Conditions for Running the DTC


• Battery voltage must be between 9-16 V.
• Brakes applied
 Conditions for Setting the DTC


C0277 06 or C0890 03

• 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 V reference circuit.

C0277 07 or C0890 07

• 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.

C0277 4B

The DTC will set when the brake pedal position sensor home position is not learned.

  Action Taken When the DTC Sets

Brake lights always ON.

 Conditions for Clearing the DTC

The condition for setting the DTC is not longer present.

 Diagnostic Aids

C0277 4B

If the DTC is set, recalibrate the brake pedal position sensor.

C0277 09

If the DTC is set, replace the brake pedal position sensor. If the DTC resets, replace the BCM.

 Reference Information

 Schematic Reference

Exterior Lights Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Exterior Lighting Systems Description and Operation

Electrical Information Reference


• Circuit Testing

• Connector Repairs

• Testing for Intermittent Conditions and Poor Connections

• Wiring Repairs


Scan Tool Reference

Control Module References for information on diagnostic tools

 Circuit/System Verification

Ignition ON, observe the scan tool Brake Switch parameter. The reading should be between Inactive/Active and change when the brake pedal is pushed or released.

 Circuit/System Testing


C0277 06 or C0277 07

1. Ignition OFF, disconnect the harness connector at the B22 Brake Pedal Position Sensor.
2. Ignition OFF, test for less than 6 Ω between the low reference circuit terminal C and ground.
3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
4. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal A and ground.
5. If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
6. If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
7. Test for less than 0.3 V between the signal circuit terminal B and ground.
8. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
9. Test for 4.8-5.2 V between the 5 V reference circuit terminal A and the signal circuit terminal B.
10. If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
11. Ignition OFF, disconnect the X2 harness connector at the K9 Body Control Module.
12. Test for infinite resistance between the signal circuit terminal B and ground.
13. If less than the specified range, test the signal circuit for a short to ground.
14. If all circuits test normal, test or replace the B22 Brake Pedal Position Sensor.

C0277 09

1. If the DTC is set, replace the B22 Brake Pedal Position Sensor.
2. Perform the brake pedal position sensor recalibration procedure. Refer to Brake Pedal Position Sensor Calibration.
3. Operate the vehicle within the Conditions for Running and Setting the DTC and verify the DTC does not reset.

4. If the DTC resets, replace the K9 Body Control Module.

C0277 4B

If the DTC is set, recalibrate the B22 Brake Pedal Position Sensor.


1. Verify that the DTC sets under the conditions for running and setting.
2. Perform the brake pedal position sensor recalibration procedure. Refer to Brake Pedal Position Sensor Calibration.
3. Operate the vehicle within the Conditions for Running and Setting the DTC and verify the DTC does not reset.

4. If the DTC resets, replace the B22 Brake Pedal Position Sensor.
 Component Testing


Static Test

1. Ignition OFF, disconnect the harness connector at the B22 Brake Pedal Position Sensor.
2. Test for 2.7-3.1 kΩ between the 5 V reference terminal A and the low reference terminal C.
3. If not within the specified range, replace the B22 Brake Pedal Position Sensor.
4. Sweep the sensor through the entire range while monitoring the resistance between the signal terminal B and the low reference terminal C. The resistance should vary between 1.5-2.3 kΩ without any spikes or dropouts.

5. If not within the specified range or is erratic, replace the B22 Brake Pedal Position Sensor.

Dynamic Test

1. Install a 3 A fused jumper wire between the 5 V reference terminal A and 5 V. Install a jumper wire between the low reference terminal C and ground.
2. Pull the sensor through the whole range while checking the voltage between signal connection B and low frequency connection C. The voltage should vary between 0.8 and 2.1 V without any peaks or losses.
3. If not within the specified range or is erratic, replace the B22 Brake Pedal Position Sensor.
 Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


• Brake Pedal Position Sensor Calibration

• Control Module References for information on BCM replacement, setup, and programming