BOBCAT-U0101 serious Bobcat ›

Lost Communication with Transmission Control Module (Hydrostatic)

The BOBCAT-U0101 (Bobcat) diesel fault code means: Lost Communication with Transmission Control Module (Hydrostatic). This is a serious severity code.

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Keep driving?
No — stop driving
DIY difficulty
advanced
Estimated cost
$150-$1,200
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Common Symptoms

  • Drive fault / no drive
  • Cluster shows drive warning

Probable Causes (Ranked by Likelihood)

  • CAN wiring fault between ECM and hydrostat controller Likely
  • Loose connector at hydrostat controller Possible

Frequently Asked Questions

What is Bobcat code U0101?

Bobcat U0101: Lost Communication with Transmission Control Module (Hydrostatic). This code is reported on Bobcat equipment running the described engine family.

Can I keep working with Bobcat code U0101?

Do not continue operating. Risk of engine damage or unsafe shutdown.

How much does Bobcat U0101 cost to fix?

Estimated repair cost: $150-$1,200. 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. Check connector seating at hydrostat controller.

  2. Verify CAN continuity end-to-end.

U0101 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 U0101 Duramax serious Lost Communication with TCM Hino serious Lost Communication with TCM Isuzu serious Lost Communication with TCM (Aisin / GM trans) Kubota serious Lost Communication with TCM MaxxForce moderate Lost Communication with TCM PACCAR serious Lost Communication with TCM Yanmar serious Lost Communication with Transmission / Hydrostat Controller

Commonly Affected Vehicles

  • Bobcat S650 skid steer loader (Kubota V3800)
  • Bobcat S740 / S750 / S770 / S850 skid steer loaders (Kubota V3800)
  • Bobcat T650 / T750 / T770 / T870 compact track loaders (Kubota V3800)
  • Bobcat E50 / E55 / E60 / E85 mini excavators (Kubota V3800)
  • Bobcat UW56 utility vehicle (Kubota V3800)

Related Codes

BOBCAT-U0100

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

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