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P0117 — Engine Coolant Temperature Sensor Circuit Low
CautionCoolingLimp to the next safe stop
Seen on: Heavy Truck
Engine Coolant Temperature Sensor Circuit Low. Common causes: ECT sensor shorted to ground.
Don't risk it — get a diesel tech on the truck.
Your code rides along, so nearby mechanics see the fault before they quote you.
How serious is it?
Caution. Limp to the next safe stop.
Most likely causes
- ECT sensor shorted to ground
- Wiring damage
- failed sensor
First moves (roadside)
- Check sensor signal wire for ground fault
- replace sensor
FAQ
What does P0117 mean?
Engine Coolant Temperature Sensor Circuit Low. Common causes: ECT sensor shorted to ground.
How serious is P0117?
Caution — Limp to the next safe stop.
What's the most likely cause of P0117?
The most common cause is: ECT sensor shorted to ground. Other possibilities include Wiring damage; failed sensor.
Can I keep driving with P0117?
Limp to the next safe stop. When in doubt, get a qualified mobile diesel tech on the truck before continuing.
Throwing this code right now?
Find a mechanic or related guides
General diagnostic guidance for diesel engines (Cummins, Detroit, PACCAR, Volvo, Mack and more). Not a substitute for a scan-tool diagnosis on your specific truck.