Diagnostic Instructions
DTC Descriptor
DTC C0201 04: 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 ABS/dynamic rear proportion (DRP) for the duration of the ignition cycle. |
• | The ABS indicator turns ON. |
• | The red brake warning indicator turns ON. |
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
Antilock Brake System Connector End Views
Description and Operation Reference
ABS Description and Operation
Electrical Information Reference
Scan Tool Reference
Scan Tool Data List
for EBCM
Circuit/System Verification
With scan tool installed ignition ON clear the DTCs, command the ABS solenoids ON and OFF with a scan tool. Monitor the operation of ABS solenoids turn on and off. Also, drive the vehicle in a straight line at a speed greater than 20 km/h (13 mph).
If the DTC did not set as a current DTC see diagnostic aids.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the EBCM.
- Test for less than 1.0 ohm of resistance from ground circuit terminal 26 (LE5) or 18 (LNF) and ground.
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Test for less than 1.0 ohm of resistance from ground circuit terminal 13 and ground.
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1(LNF) or 14 (LE5) and ground.
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
- Verify that a test lamp illuminates between the B+ circuit terminal 32 (LNF) or 1(LE5) and ground.
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
- If all circuits test normal, test or replace the EBCM assembly.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
Control Module References
for EBCM replacement, setup, and programming