U0121

U0121 means: Lost Communication With ABS Control Module. Network communication lost with the ABS module.

Lost Communication With ABS Control Module

Network communication lost with the ABS module.

SeverityCritical

CategoryNetwork / CAN

Est. Repair Cost$300–$1200

Code TypeNetwork

DIY RepairProfessional

💡 Pro Tip: ABS module communication faults can sometimes be resolved by cleaning the module connector.

Full Repair Estimate

$300–$1200

DIY Possible?

PRO

Severity

Critical

What does OBD2 code U0121 mean?+

U0121 stands for Lost Communication With ABS Control Module. Network communication lost with the ABS module.

What causes code U0121?+

Faulty ABS module; CAN bus fault; Blown fuse; Poor connector; Battery issue

How do I fix code U0121?+

Check ABS module fuse; Inspect wiring and connectors; Test CAN bus; Replace ABS module

How much does it cost to fix U0121?+

Estimated repair cost for U0121 is $300–$1200.

Is U0121 DIY-friendly?+

U0121 typically requires professional equipment and a qualified mechanic.