Stoplight Switch
WARNING: This page is about a different car, the 1994 BMW 525iT. However, it is still accessible from the selected car via links, so may be relevant.
Stoplight switch is located under instrument panel in front of brake pedal arm. To adjust, loosen lock nut and turn adjusting nut until contact plunger touches pedal arm. Adjust length of plunger until .20-.24" (5-6 mm) is visible. Tighten lock nut.