Check voltage on wire at temperature sensor, take the wire off the sensor,switch ignition on, and measure the voltage on the wire, it should be 10 volt, if it's to low the voltage stabilizer behind the speedo cluster needs most of the time be replaced. If the voltage is 10 volt on the wire, put it to earth , the gauge should move to hot(full scale). if this is ok too, replace the temp sensor.
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Check voltage on wire at temperature sensor, take the wire off the sensor,switch ignition on, and measure the voltage on the wire, it should be 10 volt, if it's to low the voltage stabilizer behind the speedo cluster needs most of the time be replaced. If the voltage is 10 volt on the wire, put it to earth , the gauge should move to hot(full scale). if this is ok too, replace the temp sensor.