Injector Circuit - Cylinder 3
The YANMAR-P0203 (Yanmar) diesel fault code means: Injector Circuit - Cylinder 3. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $250-$800
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Common Symptoms
- Misfire cyl 3, rough idle
Probable Causes (Ranked by Likelihood)
- Injector wiring Likely
Step-by-Step Diagnostic Procedure
Ohm-test injector 3.
Check harness routing.
Frequently Asked Questions
What is Yanmar code P0203?
Yanmar P0203: Injector Circuit - Cylinder 3. This code is reported on Yanmar equipment running the described engine family.
Can I keep working with Yanmar code P0203?
Limited operation only -- finish the current task then shut down for repair.
How much does Yanmar P0203 cost to fix?
Typical repair cost: $250-$800. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Yanmar SmartAssist / YDT) is usually required.
P0203 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: