Brake Light

Discussion in 'Troubleshooting & Diagnosis' started by DMSTAINLESS, Nov 15, 2010.

  1. DMSTAINLESS

    DMSTAINLESS Veteran Member

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    So i checked out my brake light prob,{light on dash} anyway its the proportioning valve switch. This i know cause light goes out when i unplug switch. I believe my front brakes may not b working as they should for the disc is not as shiney as the drum surface that is being used on rear. So i have bled frnts at fitting goin into prop valve, each fitting leaving prop valve, and at the calipers. i have good flow at all and have no air bubbles. So why does my dash light remain on? Could the switch be bad? I was told they rarely are they problem. Oh also i can see the rod in the prop valve moving when the brake is pumped, so i know its not seized up.
    Plz any help would be greatly appreciated. Thx
     
  2. BondoSpecial

    BondoSpecial Veteran Member Lifetime Gold Member

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    Have you bled the rears too? I think the light means your proportioning valve is not balancing properly. I'd bleed the rear brakes then the front brakes and see if it goes out, if you haven't already done that.
     
  3. Camaro4life18

    Camaro4life18 Veteran Member

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    The dash brake light on the speedometer or tach? If it is that light you are talking about, that is signaling your Parking Brake is engaged. There is a switch for it on the parking brake pedal.
     
  4. DMSTAINLESS

    DMSTAINLESS Veteran Member

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    It is not the parking brake, i have checked this by disconecting e brake switch and light stays on. Only when i disconnect the proportioning valve switch does this light go out. Unless for some reason the emergency switch is a normally closed switch.
     
  5. Yellow Jacket

    Yellow Jacket Veteran Member

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    im currently experiencing the same problem. Did you ever figure this out?

    even when I unplug the e-brake switch, the light stays on.
     
  6. Gary S

    Gary S Administrator Lifetime Gold Member

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    You have it right. The brake light serves double duty. Either the emergency brake switch or the proportioning valve switch will turn it on.
    In your case, you already know it is the prop valve turning on your light. The prop valve could be stuck. You could have a weak master cylinder that is delivering ineven pressure to the front/rear brakes.
    Sometimes a stuck prop valve can be centered again by a couple of sharp jabs on the brake pedal to deliver quick pressure to the switch.
     

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