HIGH COOLANT TEMP Cummins — High Coolant Temperature / Overheat Shutdown
At a glance
- Severity
- FAULT STOP
- Domain
- GENERATOR_SYSTEM
- Reference standard
- ISO 8528-5
What it means
The engine derates or shuts down from overheating: in a prolonged emergency the load loses its source. Typical in long runs with a dirty radiator or low coolant.
Probable causes
- Dirty radiator or heat exchange surface
- Low coolant level or leaks
- Fan, belt or thermostat failed
- Overload beyond available power
- Installation room with hot air recirculation
Where to start
Check coolant level and condition, radiator cleanliness and obstructions or recirculation in the installation room.
Full guided diagnosis in the app
The diagnostic tree for this fault has 5 guided steps with measurements, checks and resolutions. You'll find it in DataCIQ, one of the five IndexOS apps: free, works offline.
Printable sheet + Cummins updates
Leave your email: get the link to the printable Cummins error-code sheet and a heads-up when we add new codes and guides.
Double opt-in, zero spam, one-click unsubscribe.
The same fault on other brands
More Cummins codes
- FAIL TO START — Fail to Start
- FUEL FILTER CLOGGED — Degraded Fuel / Filter Clogging
- GENERATOR BREAKER TRIP — Start but No Load Pickup
- LOW FUEL LEVEL — Low Fuel Level / Fuel Starvation
- LOW OIL PRESSURE — Oil Pressure Loss / Oil Leak
- NOT IN AUTO — Not in Auto / Standby Not Ready