For 1990-2009 cars

### Circuit Description

The electronic brake control module (EBCM) and the powertrain control module (PCM) simultaneously control the traction control. The EBCM sends a serial data message to the PCM requesting torque reduction. When certain PCM DTCs are set, the PCM will not be able to perform the torque reduction for traction control. A serial data message is sent to the EBCM indicating that traction control is not allowed.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0242 PCM indicates Traction Control System (TCS) Malfunction

### Conditions for Running the DTC

• | The ignition switch is turned ON.

• | The ignition voltage is greater than 8 volts.

### Conditions for Setting the DTC

The PCM diagnoses a condition preventing the engine control portion of the traction control function and sends a serial data message to the EBCM indicating that torque reduction is not allowed. The PCM will typically set a DTC and the EBCM will set this DTC.

### Action Taken When the DTC Sets

If equipped, the following actions occur:

• | The EBCM disables the TCS for the duration of the ignition cycle.

• | The traction control indicator turns ON.

• | The antilock brake system (ABS) remains functional.

### Conditions for Clearing the DTC

• | The condition for the DTC is no longer present and the DTC is cleared with a scan tool.

• | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

### Diagnostic Aids

This DTC is for information only. As an aid to the technician, this DTC indicates that there are no problems in the ABS/TCS system.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Antilock Brake System Schematics
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