C0242

DTC C0242

DTC Descriptor

DTC C0242 00

Electronic control module (ECM) Indicated TCS Malfunction

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview





Circuit/System Description

The electronic brake control module (EBCM) and the electronic control module (ECM) simultaneously control the traction control. The EBCM sends a serial data message to the ECM requested torque reduction. When certain ECM DTCs are set, the ECM 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.

Conditions for Running the DTC

The ignition switch is in the ON position.

Conditions for Setting the DTC

The ECM 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 ECM will typically set a DTC and the EBCM will set this DTC.

Action Taken When the DTC Sets

One or more of the following actions may occur:

^ The EBCM disables the traction control system (TCS)/vehicle stability enhancement system (VSES) for the duration of the ignition cycle.
^ The Traction Control and Active Handling indicator turns ON.
^ The ABS/TCS indicators turn ON.
^ The ABS remains functional.

Conditions for Clearing the MIL/DTC

^ The condition for the DTC is no longer present.
^ The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Engine Controls Schematics

Connector End View Reference

Antilock Brake System Connector End Views

Engine Control Module Connector End Views

Description and Operation

ABS Description and Operation (Under 8600 GVW ) ABS Description and Operation (Equal to or Over 8600 GVW)

Engine Control Module Description

Electrical Information Reference

^ Circuit Testing
^ Connector Repairs
^ Testing for Intermittent Conditions and Poor Connections
^ Wiring Repairs

Scan Tool Reference

Scan Tool Data List for ECM

Circuit/System Verification

DTC C0242 will set as result of the ECM detects a malfunction and then causes traction control (TCS) shut down, until the malfunction has been corrected.

Review Powertrain Symptoms list.

1. Perform Diagnostic System Check-Vehicle. Initial Inspection and Diagnostic Overview
^ Diagnose any other Vehicle DTCs before attempting diagnosis of C0242.

2. With Tech 2, view "Signals" Data Display list under EBCM.
3. Refer to appropriate module for diagnosing any "invalid" signals.
4. If no invalid signals are present, view "Signal Fault" data in "Enhanced DTC Data"
5. Refer to appropriate module for diagnosing that invalid message data.
6. Do not replace the EBCM due to this DTC fault.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

Symptoms - Engine Controls