mike73
Newbie
Yes post a picture. In all the trucks I've owned (88 k2500, 92 c1500, 2000 silverado 1500, 1991 K2500 w/ hydroboost), I can't recall any wires coming out of a brake booster. Some of them had an ABS module below the master cylinder, but there were not any wires near the brake booster unless you're talking about the cruise servo above it or something like that. If a wire truly appears to be coming from behind the booster, I'd wonder if someone just used the brake hole in the firewall to run wires and something is getting pinched in a place that would be difficult to see.
Also, I haven't fully thought through the implications of this possibility but what if there is an open/faulty ground somewhere, maybe applying the brakes puts voltage on a ground side, causing things to turn off. This may not be consistent with it still occurring with the brake switch out, but we have to keep in mind that sometimes symptoms can be misunderstood if the problem isn't known
Also, I haven't fully thought through the implications of this possibility but what if there is an open/faulty ground somewhere, maybe applying the brakes puts voltage on a ground side, causing things to turn off. This may not be consistent with it still occurring with the brake switch out, but we have to keep in mind that sometimes symptoms can be misunderstood if the problem isn't known