Has the light come on, and stayed on? If it goes out (after a re-start) and then comes back on after a tap or 4 of the brakes, it could also be the brake light switch (stop lamp switch).

Best thing, would be to check for codes.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D