Glow Plug / Heater Circuit 'A' Malfunction
The KUBOTA-P0380 (Kubota) diesel fault code means: Glow Plug / Heater Circuit 'A' Malfunction. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- beginner
- Estimated cost
- $8-$25 per plug, $40-$120 relay
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Common Symptoms
- Hard cold start, white smoke until warm
- MIL after key cycle
Probable Causes (Ranked by Likelihood)
- Failed glow plug (one or more) - classic D/V wear item Very Likely
- Corroded glow plug bus bar Likely
- Failed glow plug relay / timer Likely
Step-by-Step Diagnostic Procedure
Ohm each glow plug - typical spec 0.5-1.5 ohm. OL means replace.
Check relay output with DMM during pre-heat cycle.
Frequently Asked Questions
What is Kubota code P0380?
Kubota P0380 means: Glow Plug / Heater Circuit 'A' Malfunction. Moderate code. Keep working cautiously and plan repair.
Can I keep using my Kubota with P0380?
Moderate fault -- continue light use, fix at next service. Use Kubota Diagmaster software (dealer tool) for full diagnostics.
How much does P0380 cost to fix on a Kubota?
Repair cost range: $8-$25 per plug, $40-$120 relay. Compact-tractor labor is typically $110-$150/hr in 2026.
P0380 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: