Yanmar Fault Codes
Yanmar builds compact diesel engines across three distinct markets: industrial / agricultural (TNV / TNE families powering Yanmar's own SA, YT, LX tractors plus rebadged equipment from John Deere, Takeuchi, Cub Cadet, and others), marine propulsion (the JH and LY families on sailboats and commercial vessels), and standby gensets. Diagnostics use the Yanmar SmartAssist or YDT dealer scan tool.
56 fault codes documented· 4 platform families · Industrial / marine / genset · 1995 - present
Most Common Yanmar Fault Codes
Showing 24 of 56 Yanmar codes, sorted by severity. Each links to causes, diagnostics, common fixes, and repair cost estimates.
YANMAR-LOW-OIL-PRESSURE critical
Yanmar Marine Low Oil Pressure Alarm
YANMAR-MARINE-BILGE-WATER critical
Yanmar Marine High Bilge Water Alarm
YANMAR-MARINE-EXHAUST-TEMP critical
Yanmar Marine Exhaust Elbow Over-Temp Alarm
YANMAR-OVERHEAT-MARINE critical
Yanmar Marine Overheat Alarm
YANMAR-P0087 critical
Fuel Rail Pressure Too Low
YANMAR-P0217 critical
Engine Coolant Overtemperature
YANMAR-SALTWATER-PUMP critical
Yanmar Marine Seawater Pump Flow Loss
YANMAR-TRANSMISSION-OIL-PRESSURE critical
Yanmar Marine Transmission Oil Pressure Low
YANMAR-U0100 critical
Lost Communication with ECM
YANMAR-ALTERNATOR-BELT serious
Yanmar Marine Alternator Belt Fault / Battery Light
YANMAR-GENSET-CONTROLLER serious
Yanmar Genset Controller Communication Error
YANMAR-GENSET-LOW-FUEL serious
Yanmar Genset Low Fuel / Shutdown
YANMAR-HYD-PILOT-FAULT serious
Yanmar ViO Pilot Pressure Fault
YANMAR-LOW-COOLANT serious
Yanmar Marine Low Coolant Alarm
YANMAR-MARINE-CRANKCASE-PRESSURE serious
Yanmar Marine Crankcase Pressure High
YANMAR-MARINE-ECU-COMM serious
Yanmar Marine ECU Communication to Helm Panel Lost
YANMAR-MARINE-FUEL-PRESSURE serious
Yanmar Marine Fuel System Low Pressure
YANMAR-P0088 serious
Fuel Rail Pressure Too High
YANMAR-P0089 serious
Fuel Pressure Regulator Performance
YANMAR-P0091 serious
Fuel Pressure Regulator (SCV) Control Circuit Low
YANMAR-P0093 serious
Fuel System Leak Detected - Large
YANMAR-P0201 serious
Injector Circuit - Cylinder 1
YANMAR-P0202 serious
Injector Circuit - Cylinder 2
YANMAR-P0203 serious
Injector Circuit - Cylinder 3
Yanmar Engine Platforms
| Platform | Years | Applications | Notes |
|---|---|---|---|
| Yanmar 3TNV / 4TNV | 2003-present | Yanmar SA, YT, LX compact tractors; Yanmar ViO mini excavators; Cub Cadet rebadged tractors; JD 17G/26G/35G; Takeuchi mini ex | TNV-series industrial Tier 4 Final compact diesels. The dominant Yanmar engine on small ag and compact construction. Common-rail with EGR + DPF. |
| Yanmar 3JH / 4JH / 6JH | 1995-present | Sailboat auxiliaries (Hunter, Beneteau, Catalina), trawlers, sportfish | Marine propulsion family. JH4 and JH5 generations; mechanical-injection on older units, common-rail on newer. |
| Yanmar 6LY / 8LV | 2005-present | Yacht and commercial marine propulsion; trawlers, ferries, work boats | High-output marine common-rail diesels (6LY3-STP, 6LY400, 6LY440, 8LV320/350/370). |
| Yanmar SY / 3TNE / 4TNE gensets | 2003-present | Industrial backup generators; portable jobsite generators | TNE-powered SY-series gensets for industrial / commercial backup power. |
Common Yanmar Issues
- High-pressure fuel pump SCV (suction control valve) failures on TNV common-rail engines
- Primary fuel filter clogging from old fuel in seasonal-use ag equipment (Yanmar service interval is 500 hr)
- Marine: heat exchanger end cap O-ring leaks causing low-coolant alarms
- Marine: failed bilge water sensors on commercial fishing vessels
- Cracked expansion tank on older YM-series sailboat auxiliaries
- Glow plug controller faults on cold-start in compact tractors
- Genset low-fuel shutdowns -- often a stuck float, not actually low fuel