Engine coolant temperature sensor failure or short to ground. Low coolant level or trapped air in the cooling system. Damaged, loose, or corroded sensor wiring/connectors.

Check coolant level only when the vehicle is cool and safe to inspect. Verify the code and live coolant temperature data with an OBD-II scanner. Inspect the temperature sensor connector and wiring for corrosion or damage.

P0117

Warning

Engine Coolant Temperature Circuit Low Input

Severity

Warning

What does P0117 mean?

Fault code P0117 means the engine coolant temperature sensor circuit is reporting an unusually low voltage or temperature signal. This can affect warm-up strategy, cooling fan behavior, drivability, and overheating protection, so the vehicle should be diagnosed soon.

Possible Causes

Engine coolant temperature sensor failure or short to ground
Low coolant level or trapped air in the cooling system
Damaged, loose, or corroded sensor wiring/connectors
Thermostat, cooling fan, or coolant pump problem

Recommended Actions

1 Check coolant level only when the vehicle is cool and safe to inspect
2 Verify the code and live coolant temperature data with an OBD-II scanner
3 Inspect the temperature sensor connector and wiring for corrosion or damage
4 Avoid hard driving if the temperature gauge or warning lights indicate overheating
5 Schedule professional diagnosis if the code returns after basic checks

Related Powertrain fault codes

P0100 Mass or Volume Air Flow Circuit Malfunction P0102 Mass or Volume Air Flow Circuit Low Input P0103 Mass or Volume Air Flow Circuit High Input P0105 Manifold Absolute Pressure/Barometric Pressure Circuit P0107 Manifold Absolute Pressure/Barometric Pressure Circuit P0108 Manifold Absolute Pressure/Barometric Pressure Circuit P0110 IAT Circuit Malfunction P0118 Engine Coolant Temperature Circuit High Input