BOBCAT-U0100 critical Bobcat ›

Lost Communication with ECM / PCM A

The BOBCAT-U0100 (Bobcat) diesel fault code means: Lost Communication with ECM / PCM A. This is a critical severity code.

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Keep driving?
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DIY difficulty
advanced
Estimated cost
$150-$3,500
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Common Symptoms

  • No-start, blank cluster, multiple warning lamps

Probable Causes (Ranked by Likelihood)

  • Broken CAN wire between controller and ECM (rubbing point in loader arm) Likely
  • Failed ECM Possible
  • Blown ECM power fuse Possible

Frequently Asked Questions

What is Bobcat code U0100?

Bobcat U0100: Lost Communication with ECM / PCM A. This code is reported on Bobcat equipment running the described engine family.

Can I keep working with Bobcat code U0100?

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

How much does Bobcat U0100 cost to fix?

Estimated repair cost: $150-$3,500. 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 ECM power at key-on; verify fuse.

  2. Terminate CAN with 60-ohm resistor reading across the bus.

  3. Flex-test harness at pivot points.

U0100 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 U0100 Duramax serious Lost Communication with ECM/PCM A Hino serious Lost Communication with ECM/PCM Isuzu serious Lost Communication with ECM/PCM Kubota serious Lost Communication with ECM/PCM MaxxForce moderate Lost Communication with ECM PACCAR serious Lost Communication with ECM/PCM Yanmar critical Lost Communication with ECM

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)
  • Bobcat S630 / S650 skid steer loaders (Doosan D24)
  • Bobcat S770 / S850 skid steer loaders (Doosan D34)
  • Bobcat T630 / T650 / T870 compact track loaders (Doosan D24/D34)
  • Bobcat E55 / E85 mini excavators (Doosan D24)

Related Codes

BOBCAT-U0101BOBCAT-U0121

Explore More

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

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