Contents: Examination ↓ Replacement ↓
Examination
1. If the coolant temperature sensor is not working, check its fuse.
 |  |
2. If the gauge indicator shows that the engine is hot when you just started a cold engine, disconnect the wire from the gauge (indicated by the arrow). If the indicator readings decrease, replace the sensor. If the readings remain the same, the indicator wiring is broken or the indicator is faulty. In the picture on the left is a 4-cylinder engine, on the right is a 6-cylinder engine.
3. If the indicator shows nothing after the engine has warmed up and the indicator fuses are intact, turn off the engine, disconnect the wire from the sensor and, using a jumper, connect the wire to the engine ground. Without starting the engine, turn on the ignition for a moment. If the indicator shows that the engine is warm, replace the sensor.
Replacement
1. Drain the coolant.
2. Disconnect the wire from the sensor.
3. Unscrew the faulty sensor and screw in a new one. Connect the wire and check the sensor operation.