For 1990-2009 cars

### DTC Descriptor

DTC C0297 00: Brake Applied Output Circuit

### Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

### Circuit/System Description

The body control module (BCM) provides a 5-volt reference voltage and a low reference signal to the brake pedal position sensor (BPPS). When the brake pedal is applied, the BPPS sends a variable voltage signal that will increase as the brake pedal is applied, through the stop lamp switch signal circuit to the BCM. The BCM then applies a signal through the stop lamp switch signal circuit to the engine control module (ECM) and transmission control module (TCM).

### Conditions for Running the DTC

• | The engine must be ON.

• | The brake must be applied.

### Conditions for Setting the DTC

The BCM detects a short to ground in the stop lamp switch signal circuit.

### Action Taken When the DTC Sets

• | The BCM stores the DTC to memory.

• | The Service Vehicle Soon indicator is commanded ON

### Conditions for Clearing the DTC

• | The condition for setting the DTC is no longer present.

• | The history DTC clears after 40 fault-free ignition cycles.

• | The DTC can be cleared using a scan tool.

### Reference Information

#### Schematic Reference

• | Antilock Brake System Schematics .

• | Body Control System Schematics .

#### Connector End View Reference

Component Connector End Views .

#### Electrical Information Reference

• | Circuit Testing .

• | Connector Repairs .

• | Testing for Intermittent Conditions and Poor Connections .

• | Wiring Repairs .

#### Scan Tool Reference

Control Module References .

### Circuit/System Verification

Ignition ON, press and release the brake pedal. The stop lamps should illuminate then go out.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the TCM and the harness connector at the ECM.
2. Connect a test lamp between the signal circuit terminal of the TCM and a known ground.
3. Ignition ON, press and release the brake pedal. The test lamp should illuminate ON and OFF when depressing and releasing the brake pedal.

⇒ | If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.

⇒ | If the test lamp does not illuminate test the signal circuit for open/high resistance. If the circuit tests normal, replace the BCM.

4. Ignition OFF, connect the harness connector at the TCM.
5. Connect a test lamp between the signal circuit terminal of the ECM and a known ground.
6. Ignition ON, depress and release the brake pedal. The test lamp should illuminate ON and OFF when depressing and releasing the brake pedal.

⇒ | If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the TCM.

⇒ | If the test lamp does not illuminate test the signal circuit for open/high resistance. If the circuit tests normal, replace the TCM.

7. If all circuits test normal, replace the ECM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References