U1021
Lost Communication With Anti-Lock Brake System Control Module
Severity
🔴 HighCan you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–278 (est.)
Symptoms
- The ABS indicator on the dashboard is on
- Disabling the stabilization system (ESP)
- Lack of response to the brake pedal in emergency situations
- Errors in other ABS-related systems
Causes
- Open or short circuit in the communication circuit
- ABS module malfunction
- Poor contact in connectors
- ABS module power problems
- Software error in ABS module
How to Fix
- Check the condition of the ABS module fuses
- Inspect the ABS module connectors and wiring harness
- Check the power and ground of the ABS module
- Scan the ABS module for errors
- If necessary, replace the ABS module