[DJ19856.2]

I own a 1985 6.2l diesel suburban and when I drove over some large bumps on a dirt road it was like I just shut the key off. (A friend had to tow me home.) The wired thing is that the 4 ways, power locks, and the brake lights do not work either. The only electrical things that work are the headlights, interior lights and the cigarette lighter plug. Does anyone know what the problem could be? I checked all the fuses and they all are good, and there is no loose connections at the batteries. The batteries also remain charged, so there is not a short grounding them out or anything like that. Any suggestions would be appreciated.
Thanks!!

 

[BlackSmoke74]

an idea

I'm gonna suggest that you crawl underneath the truck and start checking the wires near the starter and on the starter. If I remember correctly, My 85 pickup has quite a few down there that hook to the same terminal as the battery and thats where you get quite a bit of electicity from. if they don't look bad, determine the wire colors and where they go and see if they are actually conducting electricity up on top of the motor and where they tie into the electrical system. I personally feel that this is a really dumb place for them to tie in, but I'm also too lazy to fix the thing that I see as a problem. also, they may have somewhere in the line whats called a "fuzable link" this is simply a big symetrical gob of plastic formed over the wire where you could cut it apart and put a fuze in there. another dumb idea in my books.

asside from that, your other options would be some wiring harness plugs coming undone, but that kind of thing doesn't happen too often on GM products.

good luck and post back with the solution. I'm sure many of us will be entertained by it. it will also give us ideas where to look when ours dies the same way.

 

[DJ19856.2]

Yes Fixed It!!

Well as i was taking a good second going through on the wiring when I found that there is a connection of 2 positive red wires in the middle of the firewall slightly to the right of the air filter. (if you are looking under the hood from the front of the truck.) The wire to the right broke off, so i lengthened the broken wire and put a new connector on it and I have power and ignition. :cool2:

BTW, thanks for the reply.

 

[1 FATHOG BBQ]

make sure you check the ground wires, very important! make sure on the engine that the are clean and tight, there is probably a star washer between wire lug and engine block that "digs" into the block to make sure you have a ground, make sure it is not flatten out over time. look for multiple ground wires, there maybe one from the firewall to engine, there maybe one by one of the engine mounts to the frame. I cannot tell you how important grounds are. also as previously mentioned, trace all your positive wires, look for corrosion and make sure the are tight. Check your main firewall connector that it is tight.Somewhere, when you hit a bump, something is momentarilly loosing connection. Good Luck!