• | 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 provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Brake Pedal Position Sensor 5-Volt Reference | C0277 06, C0890 03 | C0277 06 | 1 | -- |
Brake Pedal Position Sensor Signal | C0277 06 | C0277 06 | C0277 07 | C0277 09 C0277 4B |
Brake Applied Signal | C0297 00 and P0571 00 | 2 | 2 | -- |
Brake Pedal Position Sensor Low Reference | -- | C0277 07 | 1 | -- |
1. Stop Lamps Malfunction 2. Cruise Control Malfunction |
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 battery voltage to the stop lamp relay control circuit. When the stop lamp relay receives battery voltage from the BCM, the relay coil is energized and the stop lamp relay switch contacts close applying battery voltage to the rear stop lamps and trailer stop lamps. The stop lamp relay control circuit also supplies voltage the center high mounted stop lamp (CHMSL) when the brakes are applied.
• | Battery voltage must be between 9-16 volts. |
• | Brakes APPLIED. |
DTC C0277 06 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. |
DTC C0277 07 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. |
The DTC will set when the BCM detects the brake pedal position sensor signal is changing faster than possible under normal operating conditions.
The DTC will set when the brake pedal position sensor home position is not learned.
The DTC will set when the BCM detects a short to ground in the brake pedal position sensor voltage reference circuit for 0.5 seconds or greater.
The DTC will set when the BCM detects a short to battery voltage in the brake pedal position sensor voltage reference circuits for 0.5 seconds or greater.
• | 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. |
• | For DTC C0277 4B the stop lamps may not activate at the expected brake pedal positions. |
• | 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. |
• | For DTC C0277 4B a successful brake pedal position sensor calibration has been performed. |
• | 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. |
Exterior Lighting Systems Description and Operation
Control Module References for scan tool information
⇒ | If the test lamp does not illuminate, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | 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. |
⇒ | 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. |
⇒ | 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. |
⇒ | If the DTC resets, replace the BCM. |
⇒ | If the DTC resets, replace the brake pedal position sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup and programming |