What usually causes it
- A failed coolant temperature sensor
- A short in the wiring or a wet, rusty plug
- A really hot engine from low coolant or a cooling problem
- A fault in the engine computer, which is not common
P0117Starts at: Get it checked this week
Coolant temperature sensor signal is too low
The coolant temperature sensor tells the computer how hot the engine is. Its signal is low, so the computer may think the engine is hotter than it is.
Check this first
Only when the engine is fully cool, look at the coolant level in the plastic tank. Never open the radiator cap on a hot engine.
What to watch for
- The temperature gauge climbing into the hot zone
- Cooling fans running all the time, or hard starting when the engine is warm
- Steam, or a sweet smell from the engine
Can I keep driving?
We rate P0117 as Get it checked this week. It is not an emergency yet, but it can get worse. If the light starts flashing, stop driving soon.
Quick answers about P0117
What does P0117 mean?
Coolant temperature sensor signal is too low. The coolant temperature sensor tells the computer how hot the engine is. Its signal is low, so the computer may think the engine is hotter than it is.
Can I keep driving with P0117?
We rate P0117 as Get it checked this week. It is not an emergency yet, but it can get worse. If the light starts flashing, stop driving soon.
What usually causes P0117?
The most common causes, in order: A failed coolant temperature sensor; A short in the wiring or a wet, rusty plug; A really hot engine from low coolant or a cooling problem; A fault in the engine computer, which is not common.
Estimates only. A mechanic should confirm. The same code can mean slightly different things on different cars; the app explains it for your exact year, make, model and mileage.