GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2004 🢒 Grand Prix 🢒 DTC 🢒 DTC C0278

Circuit Description

The body control module (BCM) applies a ground through the brake sensor reference low circuit to the brake position sensor. The BCM supplies a 5 volt reference through the brake sensor reference voltage circuit to the brake position sensor. When the brake pedal is being applied, the brake position sensor then sends a variable voltage signal through the brake sensor signal circuit to the BCM.

Conditions for Running the DTC

The battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC

DTC C0278.0 will set if the brake position sensor is out of calibration.

Action Taken When the DTC Sets

Conditions for Clearing the DTC
    • This DTC will clear on current status after the condition for setting the fault is corrected.
    • A history DTC will clear after 100 consecutive ignition cycles with out a fault present.
    • History and current DTCs can be cleared using a scan tool.

Diagnostic Aids
    • If DTC C0278 sets then recalibrate the brake position sensor.
    •  Perform a visual inspection for a loose or poor connection at all related components. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.

Does the scan tool display DTC C0278?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

3

Recalibrate the brake position sensor. Refer to Brake Pedal Position Sensor Calibration Description and Operation .

Did you complete the repair?

Go to Step 4

-

4
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.

Does the scan tool display DTC C0278?

Go to Step 5

Go to Step 6

5

Important: After replace the brake position sensor, perform the calibration procedure. Refer to Brake Pedal Position Sensor Calibration Description and Operation .

Replace the brake position sensor. Refer to Brake Pedal Position Sensor Replacement .

Did you complete the replacement?

Go to Step 6

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6
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK