Your engine coolant temperature gauge has a sensor ( there is also a engine coolant temperature sensor that is used for the computer / PCM )
Coolant Temperature Sensor
The engine coolant temperature sensor and coolant temperature gauge sender are located on the passenger's side of the engine, under the intake manifold.
seriously? it tells you what temperature you engine coolant/antifreeze is. that is how your gauge on the dash knows what your temperature is at.
This is called the Temperature light or gauge
The 1995 Lincoln Town Car coolant temperature gauge sensor can be found on the front of the engine. The coolant temperature sensor will be a few inches above the thermostat housing.
Low Coolant? Weak Temerature sensor? Weak gauge Gauge working properly and recording the thermostat opening and closing as engine temperature fluctuates
Because the motor is running to hot try flushing your radiator and putting new coolant in.
Check coolant level Could be thermostat opening and closing due to engine coolant temperature flutuation
An inoperative temperature gauge will not alter how an engine runs, but the operator will not know if the water temperature has risen above normal without a properly working guage.
If you mean the warning light just to the left of your engine temperature gauge that means that the engine coolant level in the coolant reservoir is low