Brake Lights Stay On - Electrical Issues

[BuckPennell]

I have a 99 Q45 with just over 100k. It has been perfect until the past month. I have two issues, one of them more serious than the other and I would love to have some guidance.

1. Just a couple of days ago I noticed that the brake lights were on when I was in a restaurant. I went out and checked the parking brake, I hit it with my foot sometimes when getting in or out. It was fine. I checked to see if the brake pedal was sagging, it was fine. I could see no reason why the brake light was on. I restarted the car and turned it off again, they stayed on. They stayed on all the way home and when I got home I pulled the brake light fuse so as to not run down the battery. They stayed on. I ended up pulling one of the main fuses to get them to go off. Any ideas?

2. About a month ago the automatic seat adjustment, door unlocking, that whole series of things that happen when you put the key in or take it out quit working. No huge deal with that, it was always kind of an annoyance when I turned off the car and the drivers seat would squish whomever was in the back seat anyway. But there is obviously something wrong and I'd like to make it right. This car is almost mint and I would like to keep it all nice and right. Then I wondered if the two things are connected in some way. Any thoughts?

Thanks so much!

[Q451990]

to NICO!

You will want to check out your factory service manual at www.nicoclub.com/FSM/ for more information on both of these issues.

I would check the brake lamp switch. It should be mounted above the brake pedal. You'll find two switches there, one is for the cruise control cancel function, and the other is for the brake lamps. You can see which one to check by looking at the diagram on BR-9.

There is a large section in the factory service manual about the automatic drive positioner starting on page EL-413. Before you go too far, check to make sure you haven't accidentally pressed the Cancel switch. If that's not it try the "initialization procedure" at the bottom of page EL-433.

Good luck!

Heath

[BuckPennell]

Heath, you are a hero. I checked the switches, the plastic covers on the plates were gone allowing the switch buttons to go through the hole instead of being pressed. That also explains why the cruise control quit working a while back. Thanks so much for your help! I thought it was just random electrical demons that would plague me until the car eventually dies, but instead it's a practical physical, FIXABLE problem. I appreciate it more than I can say!

[BuckPennell]

the small paddles attached to the brake pedal that push on the switches for the brake lights and the automatic speed control have holes in them. A small rubber pad is supposed to go in those holes. The rubber deteriorated over time and came out leaving the holes. The switch buttons went right through the holes without hitting anything. I glued some plastic over the holes and it fixed both the speed control and the brake lights. I'm real pleased.

[Q451990]

That's awesome! I remembered someone mentioning that there were rubber caps or something there that fall out, but I haven't dealt with it specifically, and don't know what models actually had this setup.

It might be worth picking up the rubber pads the next time you're at the dealership. I bet they're on hand and cheap. The reason I say that, is that if the plastic you used to cover the hole is thinner than what was there, the brake switch won't engage as quickly - which means the lights won't come on as quickly when you hit the brakes. Kind of picky on my part, but in an emergency braking situation, milliseconds count and could make the difference between a driver behind you rear-ending you or avoiding you...

Heath

[msscomm]

Had to chime in - same 'lil problemo on an earlier 96Q - the lower Dash cover plate had kept the pieces of the demolished "Rubber Stoppers" from falling down into sight. The part # appears to be INF 46512-H0101 Rubber-Stopper. When I P/U the plugs and get them seated, I'll post a final measurement of how proud of the surface the distance actually is - A washer taped on is a fine ole' interim hold til the parts arrive !

**The final height looks to be about 5mm proud with the INF 46512-H0101, 3 quarters thickness make a fine approximation for jury-rigging