Engine Error
U0121
Lost Communication With Anti-Lock Brake System (ABS) Control Module
Severity
Medium
Symptoms
ABS and Traction Control lights on, loss of speedometer (on some cars)
Common Causes
- Blown ABS main fuse
- Corroded connector at ABS pump
- Damaged CAN wiring
- Failed ABS module
How to Fix
- 1 Replace blown ABS fuse
- 2 Clean electrical connector with contact cleaner
- 3 Repair communication wires
- 4 Replace or rebuild ABS control module
Estimated Repair Cost
USD
$20
–
$1000
Fuse: $20; ABS Module replacement/rebuild: $400 - $1,000