Proportioning Valve Light Switch?

[dwildtoy]

Just upgraded the brakes on my 65 convertible to disc with power brakes and the proportioning valve has a light switch on the side. i cant find info on what the switch does or where to wire it to.

 

[horse sence]

The original switch is on the break pedal ,to hook up a diferent switch you would have to take the two wires from the brake pedal and hook them up to your new switch ,i would leave it at the pedal though

 

[Rusty67]

If the switch on the prop valve has a single wire, it is a ground loop for the break warning light. If the pin in the prop valve kicks to one side because of a pressure differential it will ground the circuit and the brake warning light on the dash lights up. The dash light also lights up if the parking brake is set, it is a dual purpose light. I always felt the light going on due to a brake system failure was pointless as you would certainly know it from the pedal feel (speaking from experience here).

If it is a dual wire hookup then I believe it is what horse sence said. I'm not sure which kit you bought to convert your bake system to disk/drum so it could be either.

 

[rbohm]

sorry horse sence, rusty is right. the switch on the proportioning valve is a brake warning switch. wire in a light by running power to a light, and the ground through the switch. this way you will get a warning if one side of the brake system loses pressure.

 

[dwildtoy]

Thanks for the help.

 

[horse sence]

Yes but i said brake pedal so if you take the power side and hook to your new switch your brake light circuit is already there ,actually i believe the switch completes the circuit when the pedal is pushed . Your new switch is probably a presure switch that will work in the same way ,when pressure is applied the circuit is completed .but this will only apply if it is in fact a brake light switch and not a warning light switch