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.
- Keep driving?
- No -- stop driving
- 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
Step-by-Step Diagnostic Procedure
Check ECM power at key-on; verify fuse.
Terminate CAN with 60-ohm resistor reading across the bus.
Flex-test harness at pivot points.
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?
Typical 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.
U0100 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: