Trouble Codes

P0117 Engine Coolant Temperature Sensor – Low Input

Description of DTC P0117 General

P0117 Low voltage in the ECT sensor circuit (engine coolant temperature): The purpose of this code is to test the resistance corresponding to the very high engine coolant temperature. The control is enabled whenever the engine ECM (engine control module) or PCM (power train control module) is on. If the sensor resistance is less (low voltage) than the calibration for a certain time, DTC p0117 will set

Causes of general failure code P0117

  • Faulty ECT sensor or high resistance in sensor wiring
  • A short to ground in the ECT signal circuit
  • Faulty or damaged connectors
  • Damaged wiring harness Loose terminals on the ECT or computer
  • Engine overheated
  • Worn, damaged, shorted or corroded wires and connectors.
  • Defective coolant temperature sensors.
  • Low engine coolant level. Note that other warning lights and codes may be present when the coolant level is low.
  • Poor coolant circulation.
  • Engine control module failure. Keep in mind that this is a rare event and you should look for the faults elsewhere before replacing any driver.

Symptoms of the general failure code P0117

  • Radiator fans start working moments after starting the car
  • Engine failure indicator light on
  • The AC air conditioning compressor will receive the OFF command