Lost Communication with ABS / Traction Control Module
The BOBCAT-U0121 (Bobcat) diesel fault code means: Lost Communication with ABS / Traction Control Module. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $150-$900
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Common Symptoms
- Traction control lamp on larger Bobcat utility vehicles
Probable Causes (Ranked by Likelihood)
- ABS module CAN fault on UW56 utility vehicle Possible
- Wiring damage under skid plate Possible
Step-by-Step Diagnostic Procedure
Inspect harness under skid plate.
Verify ABS module power and ground.
Frequently Asked Questions
What is Bobcat code U0121?
Bobcat U0121: Lost Communication with ABS / Traction Control Module. This code is reported on Bobcat equipment running the described engine family.
Can I keep working with Bobcat code U0121?
Usually drivable short-term, but fix soon to avoid derate or DPF issues.
How much does Bobcat U0121 cost to fix?
Typical repair cost: $150-$900. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Bobcat Service Analyzer) is usually required.
U0121 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: