Glow Plug / Heater Circuit A Malfunction
The BOBCAT-P0380 (Bobcat) diesel fault code means: Glow Plug / Heater Circuit A Malfunction. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- beginner
- Estimated cost
- $80-$350
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Common Symptoms
- Hard cold start
- White smoke at startup
- Wait-to-start lamp stays on
Probable Causes (Ranked by Likelihood)
- Failed glow plug relay (common on Bobcat S-series) Very Likely
- One or more failed glow plugs Likely
- Corroded glow plug harness under valve cover Possible
Step-by-Step Diagnostic Procedure
Current-clamp glow plug feed during key-on -- expect 40-80 A briefly on 4-cyl.
Ohm-test each glow plug at the tip (spec ~0.5-2 ohm cold).
Check relay output voltage with key-on engine-off.
Frequently Asked Questions
What is Bobcat code P0380?
Bobcat P0380: Glow Plug / Heater Circuit A Malfunction. This code is reported on Bobcat equipment running the described engine family.
Can I keep working with Bobcat code P0380?
Usually drivable short-term, but fix soon to avoid derate or DPF issues.
How much does Bobcat P0380 cost to fix?
Typical repair cost: $80-$350. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Bobcat Service Analyzer) is usually required.
P0380 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: