Diagnostic Instructions
DTC Descriptor
DTC C0201: Antilock Brake System (ABS) Enable Relay Contact 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 voltage is greater than 9.5 volts. |
| • | The solenoid relay is commanded ON. |
Conditions for Setting the DTC
One or more of the following conditions exists:
| • | 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 solenoid valves. |
Action Taken When the DTC Sets
| • | The EBCM disables the antilock brake system (ABS)/traction control system (TCS)/dynamic rear proportion (DRP) for the duration of the ignition cycle. |
| • | The ABS indicator turns ON. |
| • | The Traction Control indicator turns ON. |
| • | The red Brake Warning indicator turns ON. |
| • | The driver information center (DIC) displays the SERVICE BRAKE SYSTEM/TRACTION SYSTEM message. |
Conditions for Clearing the DTC
| • | The condition for setting 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
Connector End View Reference
Component Connector End Views
Description and Operation
ABS Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool EBCM Battery Voltage Signal parameter. The reading should be battery voltage.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the EBCM.
- Test for less than 1 ohm between the ground terminals 13 and 38 and ground.
| ⇒ | If greater than the specified range, test the ground circuits for an open/high resistance. |
- Verify that a test lamp illuminates between the B+ terminals 25 and 1 and ground.
| ⇒ | If the test lamp does not illuminate, test the B+ circuits for a short to ground or an open/high resistance. |
- If all circuits test normal, replace the EBCM.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for EBCM replacement, setup, and programming
