Checking the engine coolant temperature sensor

Fig 1: Engine Start Verification

Courtesy of VOLVO CARS OF NORTH AMERICA.

• Start the engine
• Read off the coolant temperature in the heater.

  Check that the engine coolant temperature (ECT) reading is correct. Compare with the actual coolant temperature of the engine.

  Fig 2: Identifying VCT2000 Diagnostic Tool Symbol In VIDA

  Courtesy of VOLVO CARS OF NORTH AMERICA.

Is the temperature reading OK? 

• YES 

  Refer to Checking components and wiring for contact resistance and oxidation 

• NO 

  Refer to Checking resistance of engine coolant temperature sensor