1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

Odd Brake light trouble

Discussion in 'Early CJ5 and CJ6 Tech' started by Mark Mann, May 28, 2004.

  1. May 28, 2004
    Mark Mann

    Mark Mann Kermit

    Huntsville, AL
    Joined:
    Jan 8, 2003
    Messages:
    140
    Sometimes I have brake lights and sometimes not so much brake lights. All tail and blinker lights work all of the time so I am pretty sure it's not a bad ground or the like. Seems that when I apply the brake pedal and no pressure has been built up they work fine but after I step on them once and the pressure increases no stop lights. I was wondering if maybe I should just try to replace the pressure switch? As I understand it, there is a pressure diverter (or something) and I wondered if that might cause or add to the trouble. Thanks for any input.


    MM :?
     
  2. May 28, 2004
    coby61

    coby61 Stupidiotic Member

    Prunedale CA
    Joined:
    Mar 10, 2004
    Messages:
    388
    Go to www.ronfrancis.com
    low psi switch part # SW-32....$19.95
    waterproof mech brake switch # SW-42....21.95
    Oh and the also have the most kick a$$ wiring harness kits. stress on $$. But my street rod buddies say you can call them for help and they are 1000 times better painless
     
  3. May 28, 2004
    kamel

    kamel Senior Curmudgeon

    Erlanger, Kentucky
    Joined:
    Jun 10, 2003
    Messages:
    892
    A way to test the brake switch is to take a multimeter and measure the voltage across the switch before you press the pedal.

    That is, one lead on one side of the switch, and the other lead on the other terminal of the switch.

    It should be 12 or 6 volts, depending on battery voltage.

    Have someone press the pedal - the meter should go to zero volts.

    Let up on the pedal and check the voltage - should go back to battery voltage.

    Now, once pressure has built up and the brake lights are not working or dim, measure the voltage across the switch with the pedal depressed and the lights not functioning properly. If it reads battery voltage or, say 3 - 6 volts in a 12 volt system then the switch is bad.

    If it continues to read zero when the pedal is depressed and battery when it is not depressed, the switch should be OK and look for the problem elsewhere.

    It is worth doing this test since you have to break the system open to change the switch and that could result in getting air in the lines.
     
  4. May 29, 2004
    Mark Mann

    Mark Mann Kermit

    Huntsville, AL
    Joined:
    Jan 8, 2003
    Messages:
    140
    Thanks Coby and Kamel. I will look into that website. What my major concern is at this point, is that there could be mechanical failure in either the MC or this diverter valve that I know little about. That is to say maybe there is a bypass situation and the pressure is not being applied to the rear section of the brake system. Just wondering. I assume that is why there are 2 of the pressure switches.

    MM :v6:
     

Share This Page

New Posts