C0201

DTC C0201

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.

DTC Descriptor
DTC C0201 04
- Antilock Brake System (ABS) Enable Relay Contact Open Circuit

Circuit/System Description

The solenoid relay, located within the electronic brake control module (EBCM), supplies battery voltage to all of the valve solenoids.

Conditions for Running the DTC

* Ignition ON.
* Ignition voltage is greater than 10 volts.
* The solenoid relay is commanded ON.

Conditions for Setting the DTC

* The EBCM detects an open in the battery positive voltage circuit to the solenoid valve relay.
* The EBCM detects a stuck open solenoid valve relay or an open circuit between the solenoid valve relay and solenoids.

Actions Taken when the DTC Sets

* The EBCM disables the antilock brake system (ABS), traction control and Stabilitrak for the duration of the ignition cycle.
* A DIC message and/or a warning indicator may be displayed.

Conditions for Clearing the DTC

* The condition for the DTC is no longer present.
* The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

Reference Information
Schematic Reference

Antilock Brake System Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

ABS Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 ohm between the ground circuits listed below and ground:

* Terminal 16
* Terminal 45

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuits listed below and ground:

* Terminal 2
* Terminal 31

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4. If all circuits test normal, replace the EBCM.

Repair Instructions

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

Control Module References (Programming and Relearning)for EBCM replacement, programming and setup