Need help fellow 6.5ers

[Pruittx2]

I need a wiring diagram for my 94 truck, as the one in my hayes manual sucks.

My brakelamps stoped working. out of the blue. None on the bed or the cab mounted 3rd lamp. Reverse lamps, park lamps, blinkers, and license plate lamps all work fine, just no brake lights.

So,, today I replaced the brakelamp switch,(Ac Delco unit #93801734 $20) nothing!! The fuses are good. 12V both sides, all bulbs are good. Pulled the taillamps off bed, and used my batter charger to light up all bulbs. Everything good there, pulled and clean the 13mm ground wire on left frame rail, checked for power at the rear bed wiring harness, none!
tried to trace wire's from brakeswitch,, they go up to a larger loom and into the back of the fuse box. I'd like to see where they go from there,, I'm thinking down the drivers side floor back to rear cab lamp, and then out of the cab to the rear of box. Any thoughts or ideas I might of missed? I have been doing autobody work for 22 years,, and have fixed a few cars here and there. this thing has me stumped.
They are calling for 3-6 inches of snow here for me sun eve into mon morn, and I have to plow and go to work Monday!
Heres a few pics of the darn clip that holds that switch on,,, and the switch and wires. the Purple and Violet both have 12V power with the key on.

 

[NVW]

http://www.dieselplace.com/forum/showthread.php?p=2579065#post2579065 There is a web site in this thread where you should be able to get a wiring diagram. Leo

 

[Pruittx2]

Got the PM You Guys ROCK!!!!!!

That's why I LOVE this site. This is the kind of thing We should all be proud of from our site. There's no way to fix some of these issues with out this kind of help

THANK YOU / THANK YOU / THANK YOU / THANK YOU!!!

 

[packratt]

IIRC they exit through the firewall at that pass through below the master cylinder and follow the frame rail back.

 

[Pruittx2]

:icon_bs:well according to the diagram,, and what I have in my truck they should be working,,, I have power on both sides of the Orange wire into and out of the fuse,, but not in the orange wire going into my brake switch,, from the switch the contact is made to send the 12V out of the yellow wire, and back to the lights. I'm gonna try to run a hot wire to the orange side of the switch, to see if that gets me lights, which it should, Maybe the wire coming out the back side of the fuse block is: bad, crusty, or something!!??!
I'm thinking about printing out all of those wiring pages, to put in the glove box!
What a great resource! :You_Rock_Emoticon::bow:

 

[hereismylife]

Just wondering did you see if you have voltage at the lights using a volt meter? Maybe your ground is not good. I had mine go out but I lost all my lights because of the connector at the bumper.The connector came disconnected because I lifted my truck. Electronics can be confusing.:mad2:

 

[Pruittx2]

Yeah the ground has been cleaned,,, and I ran the lights with my battery charger from the connector to make sure that all behind the connection was good.

Today,, I went out, and ran a postive jumper to the yellow wire on the switch and heard a relay clicking under the hood,,then I ran it to the orange wire on the switch and hit the brakes and the lights worked!!:fing26: There is a relay on the firewall (top edge drivers side) that was clicking when I hit the brakes,, I check the wiring diagram (thanx again) and seen that it was a center highmount stoplamp relay
I'm wondering if that is bad? :idea:? and would it cause the brake circuit to not have power after the fuse. The Zone has one for about $18 But I don't want to throw money at it if it don't need it. I ran the hot wire from the brake fuse to the brakelamp switch, and now I have brakes, so I can plow,, We've gotten about 3.5 inches in the last 2 hrs,, and we are supposed to have 6-8 by noon on Monday. :coal:

 

[Bullseye240]

The relay isn't bad if it's clicking and the brake light is coming on. the problem is that you had no power to the switch. When you ran the jumper wire you bypassed the factory hot wire and made it work. Check the connection on the backside of the fuse block for the wire you bypassed.