Coolant Temperature Sensor/Switch (For Computer): Service and Repair

Replacing engine coolant temperature (ECT) sensor

Replacing temperature sensor

Removing temperature sensor




- Remove expansion tank cap
- Raise the car.
- Remove lower splash guard.
- Position a container under engine drain cock, drain engine coolant.
- Close stopcock.
- Lower the car.

Only turbocharged (TC) engines
- Remove turbocharger (TC)/charge air cooler (CAC) and air cleaner (ACL)/turbocharger (TC) plastic hoses.
- Remove the clamp to intake manifold at turbocharger (TC) 1, 2, 3 and turn the pipe upper section to the firewall.
- Remove upper timing belt cover.
- Lift up the servo reservoir and place on top of engine.
- Remove the hose between the expansion tank and the radiator.
- Lift up expansion tank.
- Disconnect level sensor connectors.
- Place reservoir over engine.
- Remove screw to front camshaft belt cover.
- Disconnect sensor cables connectors.
- Disconnect hose for control module box air at the box.
- Hold the air hose to one side and pull up the front camshaft belt cover.
- Disconnect sensor wire connector
- Remove sensor wire cable duct screw.
- Remove thermostat housing with cable duct.
- Secure thermostat housing in a vise and remove sensor.

Note! Handle the thermostat housing carefully when securing in the vise.

Installing temperature sensor




- Install new sensor with new gasket.Tighten temperature sensor to 22 Nm.
- Ensure that the sensor cable is correctly routed in the thermostat housing and in cable duct.
- Install thermostat housing with new gasket.Tighten to 17 Nm.
- Install screw to cable duct.Tighten to 10 Nm.
- Put control module box air hose to one side and depress the front camshaft belt cover.
- Press the air hose into place in control module box.
- Install front camshaft belt cover screw.Tighten to 12 Nm.
- Connect level sensor connector.
- Install expansion tank.
- Secure the hose between expansion tank and the radiator in the expansion tank.
- Install the reservoir tank and check that the hoses lie correctly.
- Install upper camshaft belt cover.

Only turbocharged (TC) engines
- Turn intake manifold backwards to turbocharger (TC) 1, 2, 3 and tighten clamp.
- Install the plastic hoses between the turbocharger (TC)/charge air cooler and the air cleaner (ACL)/turbocharger (TC).
- Tighten hose clamps.
Then read Follow-up work.

Follow-up work

Function test
Fill coolant.
Install expansion tank cap.
Test drive the engine until the thermostat has opened.
If necessary top up the coolant.