The sensor is a thermistor powered by a stabilized voltage and is included in the pointer circuit.
Examination
1. As the liquid heats up, the current through the sensor increases and the pointer should deviate to the right. The defective sensor must be replaced.
2. If the temperature readings are incorrect, check the operation of other devices.
3. If the gauges do not work, then check the power circuit of the instrument panel.
4. In case of erroneous readings of all devices, replace the voltage stabilizer (mounted on the printed circuit board of the instrument panel).
5. If only the temperature gauge is faulty, then proceed as follows.
6. In case of low readings, disconnect the wire from the sensor and touch the mass.
7. If the arrow deviates when the ignition is on, then the sensor is faulty.
8. If the readings do not change, then remove the instrument panel (see subsection 14.9) and check the wiring from the sensor to the pointer and the power to the pointer.
9. If power is applied and the wiring is good, then the pointer is faulty.
10. If the reading is too high, disconnect the wire from the sensor.
11. If on a cold engine the arrow deviates to the left side of the scale, then the sensor is faulty.
12. If the reading does not change, then check the rest of the circuit.
Removing
On some vehicles, to access the sensor, you will need to disconnect or move aside the hoses and wiring.
1. Disconnect the battery from the ground.
2. On a cold engine, drain some of the fluid to the level of the thermal switch.
3. Disconnect the thermal switch connector.
4. Carefully unscrew the thermal switch, remove the seal (if provided).
Installation
1. Clean the thermal switch and apply sealant to the threads.
2. Replace seal (if provided).
3. Further assembly is carried out in the reverse order.