Pic. 2.184. Wiring diagram for coolant temperature sensor with ECU
The coolant temperature sensor is installed in the coolant line on the cylinder head. It measures the temperature of the coolant and sends a signal to the engine control unit. The sensor is made in the form of a thermistor sensitive to temperature changes. The electrical resistance of the sensor decreases with increasing temperature. The ECU determines the temperature of the coolant by the magnitude of the sensor signal voltage and sets the optimal enrichment of the working mixture when the engine warms up (pic. 2.184).
Pic. 2.185. Immersion of the sensor in hot coolant
Immerse the sensor in hot coolant (pic. 2.185).
Check if the resistance of the sensor is correct.
Sensor resistance:
- at a temperature of 60°C: 123.8–172.8 ohms;
- at a temperature of 115°C: 23.5–29.5 ohms.
Installation
Check that the thermostat is correctly installed in the housing and that its flange fits snugly against the housing at the installation location.
Install the coolant inlet pipe with a new gasket.
Fill the cooling system with clean coolant.
The moment of an inhaling of the gauge of temperature of a cooling liquid: 20–40 Н·м.