Genuine Volvo V70 Coolant Temperature Sensors

Volvo V70 Coolant Temperature Sensors Parts and Q&A

• Coolant Temperature Sensor
  8653103
  Q: How to replace coolant temperature sensors on Volvo V70?

  A:

  The coolant temperature sensor in the Thermostat housing is used as an engine temperature source signal for the engine management system and the instrument panel temperature gauge. If a fault occurs in the sensor, or if there is a loss of signal because of poor electrical connections a fault code is logged in the engine management system ECU which can be accessed via the diagnostic connector in the centre console using a suitable fault code reader. In the event of a logged fault code, it is important to check the sensor wiring and connector carefully and while testing by substitution with a new unit is an option, further checks should be made using Volvo test equipment by a dealer or a suitably equipped specialist. To start removal, partially drain the cooling system down to just below the level of the sensor unit which is about 2.0 litres. For petrol models up to 2001, remove the two Torx bolts and lift off the thermostat housing cover and disconnect the wiring at the adjacent connector, and unscrew the sensor out of its position in the thermostat housing. For petrol models from 2002, remove the upper timing belt cover by undoing the clips or screws, disconnect the sensor wiring plug and then remove the sensor from the thermostat housing, removing the sensor seal if fitted and making sure to use a new one. For diesel models, pull the plastic cover on top of the engine straight up and disconnect the wiring plug before unscrewing the sensor from the housing, also discard the seal if fitted and replace it with a new one. When refitting, screw in the new sensor unit with a smear of sealant on the threads or new seal as applicable and reconnect the wiring connector and reassemble the thermostat housing making sure the screws are tightened securely. Finally, reconnect radiator hose or re-fit timing belt cover or engine cover as required and top up coolant level as required.