Silly question: Purpose of idiot light above temperature gauge - Ion

I have a friend that has a 2005 Ion w/ 4-cyl 2.2L engine
There is a red light just above the temperature gauge that is intermittently glowing...
sometimes at full brightness, some times just faintly.

the light is not described in the manual that I have access to....
Which may NOT be the one that came with the car.

I'm guessing this it to warn of low coolant level in the resivoir?
But.... the coolant level is fine I think ... about an inch over the "low" level arrow/seam on the tank.

Maybe the sensor or float are fowled up? Is that common?

Any wisdom appreciated!

 

Do you have a picture?

 

She says it is the two red bars at the top of the temp. gauge that are lighting up intermittently ...
Seems very weird to me but ................ that's what she says.................

 

Ok ..................
Turns out there is a partial short in dash wiring ...
How to resolve............. hmmmmmmmmmmmmmmmm
Where's my black electrical tape ...