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Technical No Brake Lights

Discussion in 'The Hokey Ass Message Board' started by greg37, Jun 24, 2017.

  1. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    1. Hey Everyone, I'm pulling my hair out trying to find why my brake lights stopped working. a fuse was blown so I'm trying to find out why. I So checked all the wires for shorts , installed new brake switch ( pressure type) So I seem to have isolated it some, With a new fuse installed I can hit the brake 50 times and I have brake lights. When I start the car and put the car in gear ( 350 automatic )I have brake lights a few times and then there out ? I looked in the engine bay .and couldn't see any problem. I checked the trans. and noticed three wires ( red, white, black ) on a plug that plugs into something ( sorry ) on the left side of the trans. near the tail end, There is some trans fluid on the wires and the rubber boot covering the wires is pretty much gone. I don't really see how that would effect the brake lights but I thought I should mention it I would really appreciate any advice you could give me. Thanks You
     
  2. That may be the electric speedo wires. My guess you have the brakes along with something else on that fuse. Pull the fuse and see if you can figure what else isn't working.
     
    sunbeam likes this.
  3. squirrel
    Joined: Sep 23, 2004
    Posts: 55,931

    squirrel
    Member

    I'd have to imagine what the rest of the car looks like, and what parts it has in it, but the best I can figure is that it might possibly be a 1937 something.
     
  4. So do you have turn signals on that thing? "Normally" (That's not often the case here on the H.A.M.B.) the brake light switch has full batt. power then wire #2 goes to the signal switch. That's what makes one REAR light stay on while the other one blinks. Sound complicated?
    The Wizzard
     

  5. Oh, oh,,,, one more question. Did the blown fuse have anything to do with Brake lights or signals (if there's any on the car) ??
    The Wizzard
     
  6. wvenfield
    Joined: Nov 23, 2006
    Posts: 5,580

    wvenfield
    Member

    It would help if you stated what you had. Probably not your problem but on a 54 Chevy I had the top of my steering column would slide down grounding out my brake lights.
     
  7. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    Thanks for all the help, Yes the turn signals still work , It has a later year GM column , a pressure brake light switch just behind the m/c and booster. m/c mounted on frame ( replaced brake light switch ) Thanks Again
     
  8. Now we're getting somewhere. Did the signals still work when the Brake lights did not? Did you use a v.o.m. or test light to check the switch prior to replacing it? When a switch stops working it seldom will blow a fuse. It just stops making contact, no short involved. However, a short elsewhere could cause the switch to fail. If there is a next time the brake lights stop, at that time check to see if the signals are still in fact working. How do you know when the brake lights stop working? Do the Brake light and signal share the same fillement on the same bulb?
    The Wizzard
     
  9. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    Pist-n-Broke , Thanks for your reply, Yes signals still work. No I didn't check the pressure brake light switch with a test light but did check the connector to it and it is getting power.. With a new fuse I hit the brake pedal a few times and they go out I can see them reflect off the garage door., This is only after I start the engine and put the car in gear ( Auto. Trans.) With a new fuse before I start the engine I have brake lights as many times as I want ?? Thanks Wizard
     
  10. sunbeam
    Joined: Oct 22, 2010
    Posts: 6,213

    sunbeam
    Member

    The short could be anywhere in the rear turn signal brake light system. The turn signal flasher will act as a circuit breaker in the flasher side. Does your flasher become really fast at anytime?
     
  11. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    No it flashes normally.
     
  12. metalman
    Joined: Dec 30, 2006
    Posts: 3,297

    metalman
    Member

    Column shift? I'd guess it's in the steering column/ turn signal switch. Especially if it's a column shift, somethings loose/ moving/ shorting in there. Other wise I'd have no clue what putting it in gear would have to do with it.
    I lost the brake lights on my OT daily driver. Trade you problems, I'm told mine is some $800 control module gone bad:mad:. Hate new cars.
     
  13. sunbeam
    Joined: Oct 22, 2010
    Posts: 6,213

    sunbeam
    Member

    Does the car have a column shift? Metal man beat me to it . If so try unhooking the linkage at the trans and just moving the shifter.
     
  14. I'll be back this afternoon, I'm betting the issue is in the Jacket around the shift coller. I can tell you how to test for that when I return. What kind of steering column do you have?
    The Wizzard
     
  15. d2_willys
    Joined: Sep 8, 2007
    Posts: 4,285

    d2_willys
    Member
    from Kansas

    What is the fuse rated at, and is there more than two brake bulbs? If so, when the engine is running, the voltage will rise at the battery and would bring the current drawn higher and possibly right at the limit of the fuse. If you have an alternator this is entirely possible.
     
  16. Engine man
    Joined: Jan 30, 2011
    Posts: 3,480

    Engine man
    Member
    from Wisconsin

    Pressure style brake light switches are notorious for shorting out. They can leak internally and cause a fire. Ford used one to deactivate the cruise control on some 92 to 2004 vehicles that caused many fires.
    https://www.consumeraffairs.com/news04/2007/08/ford_massive_recall.html

    Is the switch being used designed for a boosted system? I don't know if the switches for the old cars can handle the pressure that a boosted system can provide. I avoid pressure switches like the plague ever since my friends 63 Mercury Comet started on fire one night.

    See if something else is on the circuit. If it has a newer steering column it was likely rewired in some fashion. The wires going to the lights run through the car and can short out along the way. It might not show up when the turn signal is used because it isn't on as long and only one bulb at a time is powered so it doesn't draw as much current.

    Intermittent problems are the most difficult to find. Perhaps connect a test light to the brake light switch to make sure it works every time. I have found things in the trunk hitting wires or light sockets. Check the bulbs too in case there is a broken filament.
     
  17. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    Thanks everyone for your replies, It is a Lokar shifter on a 350 trans., Car was rewired at some point and has the newer spade type fuses. 20amp stop light fuse, I've checked the bulbs and checked every wire I can see. It has a later year GM column which has the switch ( ? ) mounted on the lower part of the column. Replaced the pressure switch.
     
  18. BamaMav
    Joined: Jun 19, 2011
    Posts: 6,709

    BamaMav
    Member
    from Berry, AL

    Do away with the pressure brake switch and put in a good mechanical switch that works off the pedal or linkage. I had almost the same problem, new wiring, new switch, brake lights only worked when you stood on the pedal. Tried a different switch, same thing. Never blew any fuse though. Went to a mechanical switch on the pedal arm, problem solved.
     
  19. blackbeard40
    Joined: May 25, 2009
    Posts: 51

    blackbeard40
    Member
    from Maryland

    I once had a similar problem with a my 40 Ford tail light. Kept blowing fuses. I finally traced it to the tail light wire going thru the back of the housing. Over time the sharp metal had cut a hairline slice in the wire that was not visible to my eye. Found it was the left by disconnecting one tail light at a time.


    Sent from my iPad using H.A.M.B.
     
  20. Do you know what year GM column it is or weather or not it's an after market unit? Ididit style units are being knocked off in Tiawan and are known to have big issues. Post up a photos of it if you can. Next do a very close inspection of all 6 bulbs sockets. Who's wire kit do you have? Is there a fuse for both signals and brake lights?
    The Wizzard
     
  21. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    It's a stock GM column , tilt wheel, not sure what year
     
  22. If you're testing for power into the switch, test for power out of that switch with brakes applied and "no lights" condition present.

    Those pressure switches are EXTREEMLY problematic

    Do you loose power in or out of the switch with it running and in gear?
     
    czuch likes this.
  23. clem
    Joined: Dec 20, 2006
    Posts: 4,188

    clem
    Member

    I can't help wondering if the pressure switch is your problem.
    My experience with them is also negative.
    From other threads on this forum, - They seem to require absolutely no air bubbles in them, and some require specific mounting positions.
     
  24. Greg37; Myself, personally I have never in all my years seen a Hyd brake switch cause a short. Not that some people can have that issue but I have never seen it. I also don't subscribe to throwing parts in the hat knowing the problem is with them. I totally fail to see how just putting your Car in gear can have any connection to the brake lights. At this point I believe I would turn on the 4 way flashers and start moving wires at the lights around waiting for it to blow the fuse (I insert a circuit breaker in fuse slot) in hopes of finding a damaged wire. By now I would have already lifted the steering wheel off and inspected the signal switch and it's wires running up inside the column tube. If whoever wired your car used a bunch of Butt Connectors, they can be the beginning of your problem. Weight on a wire, vibration, rub, then raw wire and poof. I'd be looking for that spot myself. These issues can be a real Blister.
    Here is a little something I have been doing when installing a new wire kit. After being rear ended some 25 years ago not knowing I didn't have brake lights. I wire the in dash turn indicator lights to the rear lights not the Front lights.
    The Wizzard
     
    RICH B likes this.
  25. greybeard360
    Joined: Feb 28, 2008
    Posts: 2,074

    greybeard360
    Member

    Is there a neutral switch wired in? Of it only blows the fuse when it is in gear I would start there.

    Sent from my Moto G Play using The H.A.M.B. mobile app
     
  26. d2_willys
    Joined: Sep 8, 2007
    Posts: 4,285

    d2_willys
    Member
    from Kansas

    Go back to the wires going to the transmission. Disconnect them! Then see if the brake fuse blows. You can simply jumper the brake light switch to save having to depress the pedal. If it never blows (in any condition), then you probably have isolated the problem to the wires going to transmission.
     
  27. greg37
    Joined: Sep 9, 2013
    Posts: 255

    greg37
    Member
    from mi.

    I know there is power going out of the switch before the fuse goes out because the brake lights are on. After the fuse blows the brake lights are off so no power going out of the switch. I have pulled the steering wheel already. It doesn't have a neutral safety switch you press down on the shift lever to move it from park to drive
     
  28. So sitting parked, brake lights on, move the Low car shifter into gear and it blows the fuse?
    The Wizzard
     
  29. That's what I'm picking up out of this thread. If that's the case I'd bet on a mechanical movement of the drive line or shifter impinging on the harness some place.




    OHHH and put a neutral safety switch in it.
     
    Pist-n-Broke likes this.
  30. I'm with 31 Vicky here. Find your main harness going from dash back to taillights and look for a rub point.
    The Wizzard
     
    31Vicky with a hemi likes this.

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