Remove the rubber boot from the connector on the coolant temperature sensor.
Start the engine and warm it up to normal operating temperature, then leave it to idle.
Check with a voltmeter that the voltage between the contact «LR» And «weight» about 0.5 V.
To check the operation of the sensor, drain the coolant, disconnect the connector and unscrew the sensor. Hang it in a container of water and connect an ohmmeter between its contacts. Heat water by measuring its temperature with a thermometer. At a temperature of 20°C, the resistance of the sensor should be 2210–2690 Ohm; at a temperature of 80°C, the resistance should be 290–354 Ohm.
Replace the sensor if it is defective.
Installation is carried out in the reverse order of removal. Fill with coolant.