brake light circuit, over and over...

[m3f_speeder]

Dudes,



I just picked up a very clean, completely stock boston green/black interior 99 M3 with 50K highway miles. Original brakes with about 50% pad left. Pretty much mint. I don't think it's been run to hard...



One small problem: about half the time I get in and take it for a drive, the the computer starts giving me the "brake light circuit, see owner's manual" warning with the orange "check system" light on the instrument cluster coming on as well.



There doesn't seem to be any pattern associated with it's coming on. Sometimes it does, sometimes it doesn't. No change in performance, just an annoyance. Any suggestions or prior experience with the problem would be appreciated. Cruise control does not seem to be affected.



How do you turn the computer off if you've used the functions like range, etc? I like it dark at night so I can focus on the road, not a display.



Also, I'm getting ready to do a little stereo upgrade. I've got the stock unit (HK, for what it's worth) in there with the 6 disk changer in the trunk. Sounds slightly better than the Dodge Neon system I heard in a rental car recently. In other words, all mid, with cones that seem about ready to launch across the cockpit at anything more than conversation level. Think I should do a new head unit, amp, and speakers or just amp and speakers?



Thanks for any tips.

[m3f_Sirius_880bd69485]

Its the brake light switch under the dash. Replace it. Its about $40 from the stealer, not a hard DIY project.



If you have selcted one of the other functions on the OBC, just hit the 'check' button, and after a few seconds, the display will disappear.



I did just a headunit upgrade and it made the hk system sound wonderful.

[m3f_KUpolo]

use the search function

[m3f_2k_889896e9da]

Congrats on your new baby! Post some pics if you can.Here is a good DIY link I found doing a search here :chair:



I plan on doing mine tomorrow.



http://www.geocities.com/karlkarlb/brakeswitch.html

[m3f_speeder]

Amazing response in no time at all. I'm sold on the forum.



Sirius, about the alpine cda 9827- thats exactly the one I was looking at for $260. When you put it in, did you hook it up with the available wiring adapter and the factory amp, as in just plug it in and crank it up, or did you power your HK speakers with the headunit and rewire the whole system?



I have a line on an alpine cda 9815- a model that was dicontinued about 6 months ago. It retailed for $500 and has a bit more continuous power (27 vs 16 watts). The crutchfield fit guide says its a no go and I'm wondering if that's true or not (maybe they just want me to buy one of their new decks...)



For an idea of the look of the car, see KUpolo's shot, minus the grill badge. It's exactly the same as mine and I plan on keeping it nice and low pro, at least from the outside. We are blessed with some of the most amazing autobahn like 8 lane super speedways here in Cali and they are often wide open for 100+mph cruising. No need for extra attention from the Heaters, who also frequently cruise at 90+ and are very good at stealthy attacks from the back with skillfull use of instant on K and Ka band radar.

[m3f_Sirius_880bd69485]

Amazing response in no time at all. I'm sold on the forum.



Sirius, about the alpine cda 9827- thats exactly the one I was looking at for $260. When you put it in, did you hook it up with the available wiring adapter and the factory amp, as in just plug it in and crank it up, or did you power your HK speakers with the headunit and rewire the whole system?



I have a line on an alpine cda 9815- a model that was dicontinued about 6 months ago. It retailed for $500 and has a bit more continuous power (27 vs 16 watts). The crutchfield fit guide says its a no go and I'm wondering if that's true or not (maybe they just want me to buy one of their new decks...)



For an idea of the look of the car, see KUpolo's shot, minus the grill badge. It's exactly the same as mine and I plan on keeping it nice and low pro, at least from the outside. We are blessed with some of the most amazing autobahn like 8 lane super speedways here in Cali and they are often wide open for 100+mph cruising. No need for extra attention from the Heaters, who also frequently cruise at 90+ and are very good at stealthy attacks from the back with skillfull use of instant on K and Ka band radar.



I used the adapter and let the amp in the back drive the speakers. The only thing I had to wire was the remote turn on for the amp.. seems the harness I got didnt' want to do this for me.