C0201
DTC C0201
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) 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 (JL7) (Antilock Brake System Schematics (With RPO JL7))Antilock Brake System Schematics (Except JL7) (Antilock Brake System Schematics (Except RPO JL7))
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
ABS Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
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. Test for less than 1 ohm between the ground circuits listed below and ground.
* Terminal 25
* Terminal 1
• 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 38
* Terminal 13
• 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, setup, and programming