Trouble code
P0117
Engine Coolant Temperature Circuit Low Input
What P0117 means
The coolant temperature signal is below the plausible range, which the computer reads as an impossibly hot engine.
Symptoms you may notice
- Cooling fans running constantly
- Rich running
- Poor economy
Common causes, cheapest first
- Failed coolant temperature sensor
- Shorted wiring
- Corroded connector
Before you buy anythingThis sensor is cheap and usually the culprit. Note that many engines have two: one for the gauge and one for the computer. Replace the one the code refers to.
What to do next
- Confirm the code with your own scan tool, or have it read free at a chain parts store.
- Decode your VIN so you know your exact engine and build date.
- Work down the causes above from cheapest to most expensive.
- Search NHTSA for a recall or service bulletin covering this symptom on your vehicle.
- Read the engine buying guide before ordering.
P0117 is a generic OBD-II code, standardized across every make and model sold in the US from 1996 onward. The meaning is the same on any vehicle; the specific part and its location are not.
Parts
Parts commonly needed for P0117
These go to Amazon. We earn a commission if you buy, at no extra cost to you — see our affiliate disclosure. Which one you actually need depends on diagnosis — read the note above first.
Confirm fitment against your VIN on the listing page before ordering. A part that matches your year and model can still be wrong for your build date or engine code.