The sensor consists of the sensor itself and a wire to the indicator on the dashboard. The sensor only works when the ignition is on.
If the sensor readings are incorrect, or it does not show anything at all, first check the condition of the wire.
- Disconnect the connector from the sensor and turn on the ignition. The gauge should read "0." Now ground the wire to the cylinder block—the gauge needle should indicate the maximum temperature. This check indicates that the indicator is working properly and the sensor is faulty. Replace it if necessary.
- If the fuel sensor does not work at the same time as the coolant temperature sensor, this may be due to a blown fuse.