The button is a circuit breaker. When there is too much electrical load it will pop instead of blowing fuses or relays. BTW for a 91 in you are in the wrong forum, you may get more/better help in the e30 forum.
PRESIDENT OF THE OVER 10 YEARS OLD AND UNDER 100K MILES CLUB
1993 325i 5spd
Benfer Performance Intake
M-tech Pedals and Shiftknob
Bavarian Auto Floor Mats
Wheelskin Steering Wheel Cover
Panasonic Head Unit
Euro Projector Lights w/ black Housing
Black Housing Clear Corners
MORE TO COME!!
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