centering of pressure differential switch

[gaertner_jan]

Guys,

I just replaced the bulb in the brake warning lamp on the dash and guess what.... it won't turn off. So I pulled out the shop manual to read up on the centering procedure. Well I'm confused now. The shop manual says to loosen a tube nut on the brake system side opposite the one I bled last. In my case this would be the rear side. Then to push down the pedal slowly until the light goes off. Ummmm, but If I let go of the pedal, crawl back under the truck to tighten one of said tube nuts won't it be pulling in air? Thereby rendering bleeding process completely useless?

say whaaaat??


help! thanks, J

[Ranchero50]

I took the end caps off of the switch and drove it back centered once the offside bleeding failed to dim the light. Yes, it had rusted in place.

[Busboy]

Yes, you're going to need a lovely assistant.