Glow Plug Indicator Circuit Malfunction
The YANMAR-P0381 (Yanmar) diesel fault code means: Glow Plug Indicator Circuit Malfunction. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- beginner
- Estimated cost
- $10-$200
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Common Symptoms
- Wait-to-start lamp won't illuminate
Probable Causes (Ranked by Likelihood)
- Failed indicator bulb / LED driver Likely
- ECU indicator circuit fault Possible
Step-by-Step Diagnostic Procedure
Bench-test indicator circuit.
Replace bulb/LED.
Frequently Asked Questions
What is Yanmar code P0381?
Yanmar P0381: Glow Plug Indicator Circuit Malfunction.
Can I keep operating with Yanmar code P0381?
Usually drivable short-term, but fix soon.
How much does Yanmar P0381 cost to fix?
Typical cost: $10-$200. Yanmar SmartAssist / YDT diagnostic software is often required.
P0381 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: