The system relay, located within the electronic brake control module (EBCM), supplies battery voltage to all of the valve solenoids and to the ABS pump motor. When the relay contacts close, the EBCM monitors the voltage supplied to the valve solenoids and compares this voltage to monitored ignition voltage.
This diagnostic procedure supports the following DTC:
DTC C0201 Antilock Brake System (ABS) Enable Relay Contact Circuit
The ignition is ON.
The EBCM detects that the voltage supplied to the valve solenoids is less than 80 percent of monitored ignition voltage for 50 milliseconds.
• | The EBCM disables the ABS/dynamic rear proportioning (DRP). |
• | The ABS indicator turns ON. |
• | The brake warning indicator turns ON. |
The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.
Refer back to the diagnostic table, steps 3-7, if this DTC continues to set intermittently.
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No |
---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the DTC set? | -- | Go to Step 3 | Go to Diagnostic Aids |
Does the resistance measure within the specified range? | 0.3-1.0 ohms | Go to Step 4 | Go to Step 6 | |
4 | Use a DMM in order to measure the resistance between the high side of the pump motor and a good ground. Does the resistance measure less than the specified value? | 0L | Go to Step 6 | Go to Step 5 |
5 | Replace the EBCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 7 | -- |
6 |
Important: Following EBCM replacement, use the scan tool to perform the Tire Size Calibration procedure.
Did you complete the replacements? | -- | Go to Step 7 | -- |
7 |
Does the DTC reset? | -- | Go to Step 3 | System OK |