1970 Skylark - Disk brake, proportion valve question (brake light on)

Discussion in 'Chassis restoration' started by Nearing, Sep 25, 2022.

  1. Nearing

    Nearing Well-Known Member

    Quick question...

    My dash brake light is on (not caused by the emergency brake being applied) and the brakes work fine, no issues. However, the proportion valve electrical sendor appears to be triggering the dash brake light. When I disconnect the brown/white wire connected to the sendor, the dash brake light goes off.

    Is the sendor faulty? Any guidance addressing this issue would be appreciated. Proportioning Valve.jpg
     
  2. TrunkMonkey

    TrunkMonkey Well-Known Member

    The light is supposed to come on if the shuttle valve inside moves to block the flow to the front or rear if one of them looses fluid or if there is air in that section's lines.

    But the switch can also fail.

    You can remove the switch and check it with an Ohm meter. The switch should be "normally open" , and show "infinity" when the plunger is depressed.

    If you bleed the system, the "tool" screws in the switch port to keep the shuttle centered during the bleeding.

    https://www.amazon.com/WISPAUSU-Com...cphy=9025796&hvtargid=pla-1128070711188&psc=1
     
  3. Nearing

    Nearing Well-Known Member

    Thanks Michael.
     
  4. TrunkMonkey

    TrunkMonkey Well-Known Member

    Let us know how it goes. :)
     
  5. Duane

    Duane Member

    I have also seen where the e-pedal comes down a little and sets the light off.

    This usually happens when the spring on the front cable rusts/breaks and will not hold up the e-brake pedal.

    You can check this by manually holding the pedal assembly all the way up and seeing if the light goes off.
    Duane
     

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