Totally Integrated Power Module
It's located under the hood and is often called a PDC (power distribution center) or the outer fuse box.
The fact that your saying the light will come on, but then go out after a few moments reinforces my suspicion of the TIPM.
If you're lucky, its a loose connection.
But when you turn the switch on, a signal is sent to the TIPM that tells the light to turn on.
A TIPM is a horrible, horrible design that we can thank the Germans for.
If it is a TIPM, the problems will be begin to appear like a domino effect. Usually the fuel pump relay circuit goes and you'll have an intermittent no start situation.