Yanmar Marine Transmission Oil Pressure Low
The YANMAR-TRANSMISSION-OIL-PRESSURE (Yanmar) diesel fault code means: Yanmar Marine Transmission Oil Pressure Low. This is a critical severity code.
- Keep driving?
- No -- stop driving
- DIY difficulty
- advanced
- Estimated cost
- $10-$4,500
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Common Symptoms
- No shift, slip
- Transmission alarm
Probable Causes (Ranked by Likelihood)
- Low ATF in Kanzaki / ZF marine gear Likely
- Worn clutch packs Possible
- Failed shift cable sticking between positions Possible
Step-by-Step Diagnostic Procedure
Check ATF level at dipstick (engine running, in neutral).
Verify shift cable reaches full travel at both helm and trans.
Pressure-test clutch circuits.
Frequently Asked Questions
What is Yanmar code MARINE-TRANS?
Yanmar MARINE-TRANS: Yanmar Marine Transmission Oil Pressure Low. This code is reported on Yanmar equipment running the described engine family.
Can I keep working with Yanmar code MARINE-TRANS?
Do not continue operating. Risk of engine damage or unsafe shutdown.
How much does Yanmar MARINE-TRANS cost to fix?
Typical repair cost: $10-$4,500. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Yanmar SmartAssist / YDT) is usually required.