BOBCAT-U0121 moderate Bobcat ›

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.

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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

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?

Estimated repair cost: $150-$900. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Bobcat Service Analyzer) is usually required.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

  1. Inspect harness under skid plate.

  2. Verify ABS module power and ground.

U0121 on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

Gas / Automotive (OBD-II) Generic OBD-II definition for U0121 Duramax serious Lost Communication with ABS Module Hino moderate Lost Communication with ABS Control Module Isuzu moderate Lost Communication with ABS Control Module Kubota serious Lost Communication with ABS Module PACCAR serious Lost Communication with ABS Module

Commonly Affected Vehicles

  • Bobcat UW56 utility vehicle
  • Bobcat UW32 utility vehicle

Related Codes

BOBCAT-U0100

Explore More

More Bobcat codes → Diesel home All diesel codes Heavy-duty Guides

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