Behind the cluster are a series of brown (ground) wires secured to the brake pedal brace under one bolt. Remove and clean these ground connections. The brakes lights activating is taking the ground path from the dash cluster.

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81 300CD (sold) 1972 280 SEL 4.5 (sold) 1966 250 S 4 spd (sold) 1974 450 SL (sold) 86 BMW 325ES (sold), 1973 280C (sold) 1988 300 SE.