Umpire613

I need a serious reset as have been working on this for a couple of days.
What I so know.
1. the brake lights are on anytime the negative battery lead is connected. they will go out if disconnected from the brake switch on the pedal. switch has been replaced.
2 thought some how the multi function headlight switch was shorted. replaced that no effect.
If I push the pedal the brake light do not get any brighter
3. the hazard light, turn light and other functions work fine. I mean the lights are still on but they blink as they should.
I am at a loss. as to where to look. we did replace the steering column so anything is possible.
and well the fuel pump. issue has all new wiring and pump. along with the sending unit which doesn't work either. or reads. if you will. ground is good everywhere. so. that's not an issue.

Umpire613

partial follow up.. we found a broken wire to the fuel pump. it was after the inertia switch and between the firewall connection to the cab. so it is somewhere inside the cab.

What we did. we shorted both the wires on the initera switch, and ran a new wire all the way to the fuel pum.. work s like a champ.
the fuel gage is still not working right . however and it checks fine. . oh well..

so at least now we can get thee thing running . maybe.
We still have the brake light issue. brake light on all the time. if you disconnect the switch on the pedal light go out. ok. makes sence. if you plug them in. the light are on and cant tell if they are working or not.
however. the turn indicators, back up light come on and work like normal.
so I think we have a short under the dash.

we put in a rebuilt steering colum in our truck rebuild, flashers work correct as well.
so I am betting in a short either in the steering colum or in the instrument cluster some where. around there.
we have had the truck in a million pieces are just finish putting it together after new everything. I mean down to new bolts. and removing all rust. on the cab and corners etc. a total rebuild.
so it could be any where.
so were just now firing it up after nearly 2 years apart on my driveway.

Chris_1

iTrader: (1)

Maybe your brake light switch is faulty (even new ones) or not installed correctly. Try removing it from the pedal assembly and operating it that way, just to see.
I don't see what year your truck is but the dash switch can cause issues on 92-96 for sure. Even on single tank trucks, I think there may be a plug behind the dash bezel that has to be plugged in.