Uxxxx · Network
U0121
Lost Communication with ABS Control Module
ModerateNetwork ECU
What it means
The reporting module cannot see the ABS module on the CAN bus. ABS warning light is typically also illuminated.
Common causes
Listed in rough order of frequency. Verify with vehicle-specific service info before parts replacement.
- 01ABS module unpowered or failed
- 02CAN bus fault to ABS module
- 03Wheel speed sensor harness short pulling the ABS module offline
Affected systems
ECUs and subsystems that report or are affected by this code.
ABS moduleCAN bus
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