Results 1 to 15 of 15

Thread: Electrical Issues-Brake Lights and Top

  1. #1
    Join Date
    Nov 2015
    Location
    Texas
    Posts
    35
    My Cars
    2000 BMW Z3

    Electrical Issues-Brake Lights and Top

    I've had a couple of electrical issues I want to address and they may all be related. Withing a month or so I had one of my brake lights go out, shortly after they both went out, and now the soft top which ran well and strong doesnt activate when I push the button. Any ideas where I can start diagnosing the problem? There have been heavy rains and there is potential for water to get into my car from the convertible boot because of dripping.

    I have no experience with electrical systems as of yet and all of my problems have been mechanical in nature so far. Any advice would be appreciated.

  2. #2
    Join Date
    Jul 2004
    Location
    Houston, TX
    Posts
    12,459
    My Cars
    36 Cylinders
    Most likely the brake light switch on the pedal. Easy fix.

  3. #3
    Join Date
    Feb 2005
    Location
    Denver, Colorado
    Posts
    1,922
    My Cars
    MRster / Z4 M4i / X5 M50
    Quote Originally Posted by 328 Power 04 View Post
    Most likely the brake light switch on the pedal. Easy fix.
    This would be an odd fix since both brake lights didn't stop working at the same time. I would check it though because it may be coincidence that one light burned out and then the brake switch gave up.
    2002 M Roadster, Steel Gray Metailic, Gray Nappa Leather, Black Soft Top, Steel Gray Metailic Hard Top, TC Kline Double Adj Shocks with H&R Springs, Stromung Exhaust, SSR Type C Wheels. Looking for a new home.

    2022 Z4 M40i, Misano Blue Metallic, Prem Pkg, Driver Assistance Pkg

    2023 X5 M50, Phytonic Blue, Black Extended Merion Leather, Driving Asst Pro Pkg, Park Asst Pkg, Exec Pkg, Climate Comfort Pkg.

  4. #4
    Join Date
    Jan 2008
    Location
    Arida Zona
    Posts
    30,107
    My Cars
    z3
    Quote Originally Posted by khammack View Post
    This would be an odd fix since both brake lights didn't stop working at the same time. I would check it though because it may be coincidence that one light burned out and then the brake switch gave up.
    Could have just had a bulb burn out, then the brake switch went out. Brake switch was my first thought as well...
    Quote Originally Posted by gonrico View Post
    Withing a month or so I had one of my brake lights go out, shortly after they both went out, and now the soft top which ran well and strong doesnt activate when I push the button.

    Going into my TENTH YEAR of providing high quality reproduction BMW fabrics!

    PRICE CUT on ALL FABRICS
    Offering the best prices on the best quality reproduction fabrics!

  5. #5
    Join Date
    Jul 2004
    Location
    Houston, TX
    Posts
    12,459
    My Cars
    36 Cylinders
    But, it is worth checking the trunk wiring loom for wire damage.
    -Abel

    - E36 328is ~210-220whp: Lots of Mods.
    - 2000 Z3: Many Mods.
    - 2003 VW Jetta TDI Manual 47-50mpg
    - 1999 S52 Estoril M Coupe
    - 2014 328d Wagon, self-tuned, 270hp/430ft-lbs
    - 2019 M2 Competition, self-tuned, 504whp
    - 2016 Mini Cooper S

  6. #6
    Join Date
    Dec 2011
    Location
    Riga, Latvia
    Posts
    1,326
    My Cars
    2x 1997 BMW Z3 2.8
    For soft top to start working, you need to press on brake to engage brake switch, press on the soft top button, and at the same time tilt the front part of the soft top, engaging the microswitch over drivers left shoulder where soft top folds. Seems like your problem most probably is with brake switch, but microswitch is well known for failing too, so check that if your brake lights work and soft top - not.

  7. #7
    Join Date
    Nov 2015
    Location
    Texas
    Posts
    35
    My Cars
    2000 BMW Z3
    Thanks for the advice guys, I'll investigate and update this weekend when I have time.

  8. #8
    Join Date
    Nov 2015
    Location
    Texas
    Posts
    35
    My Cars
    2000 BMW Z3
    So I installed a new switch... problems are unchanged. Maybe the switch is bad so I requested another... All typical symptoms are there... brakes, top, and cruise control. What else could it be???? Hopefully the switch was just bad.

  9. #9
    Join Date
    Dec 2007
    Location
    Great Dismal Swamp
    Posts
    16,026
    My Cars
    E36/7 E36/8x2 E46 F25
    While I have seen the asian sourced switches sold by the chain autoparts stores fail in a matter of weeks, I can't say I've ever seen one DOA. Make sure you have it adjusted correctly. Don't push the slider in, let the pedal do it. The next step would be putting a test light on things. This should have been the first step; I am not a fan of diagnosing by random parts replacement. The Blue and red wire is for the lights. If that tests good, the most likely juncture is splice X181 in the driver's footwell.


    /.randy

  10. #10
    Join Date
    Oct 2012
    Location
    Louisville, KY
    Posts
    4,503
    My Cars
    1997 BMW Z3 1.9L 5MT
    The brake light switch can be tricky to replace. I have not done it. Simple as it sounds, some people have trouble. I wonder if the destruction of the old switch is necessary. One person bent the bracket in forcibly removing the switch, which is stronger than the bracket, and this caused the new switch to not work properly.
    http://www.bimmerforums.com/forum/sh...6#post28358366
    http://perkornhall.se/Per_Kornhall/Brake_light.html
    https://www.bimmerforums.com/forum/s...5#post25267405
    http://www.bimmerforums.com/forum/sh...6#post28368906
    http://www.nmia.com/~dgnrg/page_25.htm
    Last edited by Vintage42; 06-07-2017 at 07:24 PM.
    BMW MOA 696, BMW CCA 1405

  11. #11
    Join Date
    Dec 2007
    Location
    Great Dismal Swamp
    Posts
    16,026
    My Cars
    E36/7 E36/8x2 E46 F25
    I've changed the switch in many cars. No destruction is necessary. The only tool needed is a coin.


    /.randy

  12. #12
    Join Date
    Oct 2012
    Location
    Louisville, KY
    Posts
    4,503
    My Cars
    1997 BMW Z3 1.9L 5MT
    The coin is used to remove the lower panel.
    http://www.bimmerforums.com/forum/sh...6#post28358366
    Last edited by Vintage42; 06-08-2017 at 12:53 PM.
    BMW MOA 696, BMW CCA 1405

  13. #13
    Join Date
    Nov 2015
    Location
    Texas
    Posts
    35
    My Cars
    2000 BMW Z3
    I swapped the switch and still no fix. Is there a fuse dedicated the brake light or something?

  14. #14
    Join Date
    Oct 2012
    Location
    Louisville, KY
    Posts
    4,503
    My Cars
    1997 BMW Z3 1.9L 5MT
    Quote Originally Posted by gonrico View Post
    ... All typical symptoms are there... brakes, top, and cruise control...
    Fuse 46 should be brake lights and cruise control. See if that is what your fuse box lid shows.
    Last edited by Vintage42; 06-09-2017 at 09:10 PM.
    BMW MOA 696, BMW CCA 1405

  15. #15
    Join Date
    Nov 2015
    Location
    Texas
    Posts
    35
    My Cars
    2000 BMW Z3
    Bingo... it was a fuse... it was obviously burned out.

Similar Threads

  1. Replies: 3
    Last Post: 04-09-2014, 05:28 AM
  2. Brake Lights and Electrical Issues
    By bimmer1985 in forum 1991 - 1999 (E36)
    Replies: 9
    Last Post: 03-21-2013, 11:52 PM
  3. Electrical issue: my brake light and turn signal are best buds
    By geezerman402 in forum 1983 - 1991 (E30)
    Replies: 4
    Last Post: 04-12-2010, 11:15 PM
  4. Brake light and Top liner issues
    By DGarri in forum 2002 - 2008 Z4 (E85, E86)
    Replies: 5
    Last Post: 03-09-2009, 12:40 PM
  5. Electrical Issues, Brake Light Circuit, Fuel Gage, Windshield Wipers
    By Paul Strefling in forum 1991 - 1999 (E36)
    Replies: 3
    Last Post: 09-11-2008, 05:47 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •