Diagnostic Test
- CHECK FOR AN ACTIVE DTC
- Perform any Service Bulletins that may apply.
- Turn the ignition on.
- With the scan tool, read ABS DTCs and record on the vehicle repair order.
- With the scan tool, erase ABS DTCs.
- Cycle the ignition from off to on.
- Press and hold the brake pedal.
- Push the EPB Switch to release the Electric Park Brakes.
- Push the EPB Switch to set the Electric Park Brakes.
- Push the EPB Switch to release the Electric Park Brakes.
- Release the brake pedal.
- Cycle the ignition from off to on.
- With the scan tool, read ABS DTCs.
Did the DTC return?
Yes
- Go To 2
No
- The conditions that caused this code to set are not present at this time. Using the appropriate SYSTEM WIRING DIAGRAM/schematic as a guide, inspect the wiring harness and electrical connectors.
- Perform the EPB VERIFICATION TEST. Refer to EPB VERIFICATION TEST .
- CHECK BRAKE CALIPERS
- This error may arise due ABS control unit overtemperature. Check whether the brake calipers are blocked.
Blocked brake calipers
Yes
- Wait for the ABS control unit to cool and restore correct operation in the brake calipers.
No
- Go To 3
- This error may arise due ABS control unit overtemperature. Check whether the brake calipers are blocked.
- CHECK CONNECTIONS ON BRAKE CALIPERS AND REAR BRAKE CALIPER MOTORS
- Check for loose, damaged or corroded connections on the brake calipers or the rear brake caliper motors.
Are there any loose or damaged connections?
Yes
- Repair the wiring connections as necessary.
No
- Go To 4
- Check for loose, damaged or corroded connections on the brake calipers or the rear brake caliper motors.
- CHECK CONNECTIONS ON REAR BRAKE CALIPER MOTORS AND ABS CONTROL UNIT
- Check for loose, damaged or corroded connections on the rear brake caliper motors or the ABS control unit.
Are there any loose or damaged connections?
Yes
- Repair the wiring connections as necessary.
No
- Go To 5
- Check for loose, damaged or corroded connections on the rear brake caliper motors or the ABS control unit.
- CHECK WIRING BETWEEN REAR BRAKE CALIPER MOTORS AND ABS CONTROL UNIT
- Check the wiring for an open circuit or high resistance between the rear brake caliper motors and PINS 2, 3, 12 and 13 of connector A on the ABS control unit.
Is there a high resistance or open condition in the wiring?
Yes
- Repair the open circuit or high resistance in the wiring.
No
- Go To 6
- Check the wiring for an open circuit or high resistance between the rear brake caliper motors and PINS 2, 3, 12 and 13 of connector A on the ABS control unit.
- CHECK WIRING BETWEEN REAR BRAKE CALIPER MOTORS AND ABS CONTROL UNIT
- Check the wiring for a short circuit between the rear brake caliper motors and PINS 2, 3, 12 and 13 of connector A on the ABS control unit.
Is there a short circuit in the wiring?
Yes
- Repair the short circuit in the wiring.
No
- Go To 7
- Check the wiring for a short circuit between the rear brake caliper motors and PINS 2, 3, 12 and 13 of connector A on the ABS control unit.
- CHECK RELATED HARNESS CONNECTIONS
- Disconnect the ABS Module harness connector.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
- Proper connector installation.
- Damaged connector locks.
- Corrosion.
- Other signs of water intrusion.
- Weather seal damage (if equipped).
- Bent terminals.
- Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
- Terminals that have been pushed back into the connector cavity.
- Perform a terminal drag test on each connector terminal to verify proper terminal tension.
Repair any conditions that are found.
- Connect the ABS Module harness connector. Be certain that the harness connector is fully seated and the connector lock is fully engaged.
- Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Connect the related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.WARNING:
To avoid possible serious or fatal injury, check brake capability is available before road testing.
- Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
- With the scan tool, read ABS Module DTCs.
Did the DTC return?
Yes
- Replace the Anti-lock Brake System (ABS) Module in accordance with the Service Information. Refer to MODULE, ANTI-LOCK BRAKE SYSTEM (ABS), REMOVAL AND INSTALLATION .
- Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .
No
- The wiring or poor connection problem has been repaired.
- Perform ABS VERIFICATION TEST. Refer to ABS VERIFICATION TEST .