Toyota Repair: Toyota Corolla Temperature Malfunction, toyota corolla, radiator fan

Question
Hello there.  I have here a Toyota Corolla '97 at 159,000
kilometers in its odometer. My problem is its TEMPERATURE
GAUGE which fluctuates from time to time. Once ignition
switch is turned to ON position, the pointer goes up all the
way beyond its maximum point then goes down halfway then up
again. It seems to me a "VU Meter in action". Same condition
even if engine is not running at ignition switch is in ON
position. First I suspect its temperature sensor, but the
radiator fan works well. Thanks in advance sir.

Answer
The radiator fan has a seperate temp sensor has nothing to do with the gauge, it has another sensor on the engine with a single wire connector on it located near the thermostat housing, this is for the gauge only.  Check the connection first and if it's ok replace this sensor.