Wiring question re handbrake warning light

Discussion in 'Mech Tech' started by AndyC, Sep 29, 2015.

  1. Go and do it now!!
     
  2. Ah dude, it takes me ages to get that poxy dash out...... :p

    And it's cold out.

    And dinner's nearly ready.

    And then what am I gonna have to tinker with tomorrow?! :)
     
  3. Did the dog eat your dinner as well? Tut
     
  4. For what it's worth, if there is a brake warning light on the actual dash cluster, that is NOT on.
     
  5. No there isn't one in the dash cluster, just the one you are trying to sort
     
  6. That'd be why it's not on then :)

    Will report back tomorrow.

    Cheers.
     
  7. theBusmonkey

    theBusmonkey Sponsor

    Watching this with interest. Ours always worked as per standard however after laying up last winter upon the restart the red light stayed on as per AndyC.
    I went through the system, replaced both switches, bled it all down and apart from a sticky caliper all was good. Good enough to travel the 7k we did last year....except the light stayed on!
    My solution has been to stick black insulating tape over the red light as what you can't see can't hurt :D
    I guess it needs sorting somehow but I'm confident the brakes are good so I figured it may be that complicated little lamp having an eppy after nearly 40 years?
     
    Iain McAvoy and AndyC like this.
  8. I will endeavour to help you if I can! :)
     
    theBusmonkey likes this.
  9. Tried disconnecting the handbrake connection?
     
  10. theBusmonkey

    theBusmonkey Sponsor

    Can't remember Snotty, I went through it all last year but I will have another look this evening. I occasionally tentatively peel back the tape & have a peek in the vain hope it's cured itself...
     
  11. Nope. No such luck. Light still comes on and won't go out.

    Might try and source a 4 pin bulb and see if that cures it.
     
  12. Does it go out when you start the engine?
     
  13. No, tried that as well.

    Before, it would go on/off just with the ignition on.

    The only thing that is different with my wiring, is the diagram for the 5 pin says it uses a blue wire instead of the white/yellow wire to go to terminal 61.

    But having read a thread by Dicky about blowing his alternator doing this wiring, I'm a bit reluctant to be plugging any blue wires into it!
     
  14. Have you checked the Haynes manual? I was wiring mine in the other day and just referred to the wiring diagram in the Haynes.
     
  15. Not got it with me.
    But interesting to know it's in there.
    Cheers
     
  16. Having done some more reading, IF there is a fault with the master cylinder / braking system, then the light should still only come on when the brakes are pressed.

    Mine is on all the time.

    I think it's likely that the bulb is the wrong one.
    There were clearly four and five pin ones for a reason!
     
  17. In addition to the above, the rear brake lights do work, so I don't see it being a problem with either of the two brake switches.
    Correct me if I'm wrong, but they would stop the rear brake lights from coming on also?
     
  18. No, the wiring's arranged such that the brake lights will come on even if there's a fault in one of the braking circuits.
     
  19. Poop! :lol:
     
  20. Right, the hunt continues.

    I wanted to rule out a defective brake switch before I buy a new warning light.

    I have followed the Bentley guide on testing them.

    Screen Shot 2015-09-30 at 16.43.34.png

    So:

    1) I turned ignition on and checked that rear brake lights came on. They did.
    2) I removed the front brake switch terminal and checked the rear brake lights came on. They did.
    3) I reconnected the front brake switch terminal, removed the rear brake switch terminal, and checked the rear brake lights came on. They did.

    I am therefore reasonably happy that both switches are still functioning, and I have brakes!
     

Share This Page