Glow Plug / Heater Circuit A Malfunction
The YANMAR-P0380 (Yanmar) diesel fault code means: Glow Plug / Heater Circuit A Malfunction. This is a serious severity code.
Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- beginner
- Estimated cost
- $80-$300
What Are the Symptoms of YANMAR-P0380?
- Hard cold start, wait-to-start lamp on
What Causes YANMAR-P0380? (Most Likely First)
- Failed glow plug relay Very Likely
- One or more failed glow plugs Likely
Can I Still Drive with YANMAR-P0380?
Yes, but fix soon. YANMAR-P0380 is rated serious severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring it.
Frequently Asked Questions
What is Yanmar code P0380?
Yanmar P0380: Glow Plug / Heater Circuit A Malfunction. This code is reported on Yanmar equipment running the described engine family.
Can I keep working with Yanmar code P0380?
Usually drivable short-term, but fix soon to avoid derate or DPF issues.
How much does Yanmar P0380 cost to fix?
Estimated repair cost: $80-$300. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Yanmar SmartAssist / YDT) is usually required.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose YANMAR-P0380?
Clamp-meter glow plug feed (40-80A briefly on 4-cyl).
Ohm-test each glow plug (0.5-2 ohm cold).
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0380 as a generic OBD-II code)
P0380 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
Which Vehicles Commonly Get YANMAR-P0380?
- Yanmar SA221 / SA324 / SA424 compact tractors
- Yanmar YT235 / YT347 / YT359 compact tractors
- Yanmar LX4100 / LX4900 utility tractors
- Yanmar ViO17 / ViO25 / ViO35 / ViO45 / ViO55 / ViO80 mini excavators
- Yanmar B27-3 / B37-3 / B50-3 compact excavators
- Cub Cadet Yanmar Ex3200 / Lx410 compact tractors (rebadged)
- John Deere 17G / 26G / 35G compact excavators (Yanmar powered)
- Takeuchi TB210R / TB216 / TB230 mini excavators (Yanmar powered)
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