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.
- 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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