1986 BMW 528e Electrical

[gottfried]

Just bought a neglected E28 and trying my best to figure things out. I don't seem to have any brake lights except the one by the rear windshield. I check for voltage at the taillight, and have 12V when I pushed the brake pedals. However, the stop lights did not come on even though the bulbs are still good. Also, the windows and dash decided to quit on me couple of days ago. I changed all the fuses to make sure that everything is right. I've been looking for solutions but got stuck. Anyone have any ideas on how to figure out these electrical problems?

[Mike W.]

On the brake lights, the ground is thru 2 pieces of galvanized metal where it's folded over, my guess is that's where your problem is. Not a great design. There's a variety of ways to fix it if that is the problem, there's a guy here selling an "octopus" which is a mini harness designed to eliminate the problem, or you can run a screw in thru both plates or even solder them together. On soldering, you need a lot of heat, a gun, not an iron, and patience.

Windows may be as little as the circuit breaker down by your knee on the kick panel. Dash lights I dunno, maybe check the brightness adjustment wheel on the switch.

Here's a pic of a couple of way to ground the brake lights.

[gottfried]

Thanks for the help Mike! I figured it out just by sanding the connections. Turns out all the connections are severely corroded. I came up with another problem on the blinkers and reverse light. I did not have a front bumper yet therefore does not have front blinkers. However, on the rear I only get about 6V for the blinkers and everytime I turned it on it makes this weird buzzing sound. The reverse light does not have any volts at all when I put the car in reverse. Do you or anyone by any chance know how to fix this?

[demetk]

The corrosion will come back. This is one way to fix the problem,