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Anyone got a wiring diagram for 84 GMC

Discussion in 'Truck & Equipment Repair' started by genrock, Sep 29, 2006.

  1. genrock

    genrock Member
    Messages: 60

    Okay I have an 84 GMC Sierra K10 1/2 ton pick up 4wd 350. Problem is I have some rotted wires. I discovered that the alternator shock wire was burned in half probably from some previous owners ignorance. But I also have a few more problems. Dash Lights cig lighter out. Parking lights and brake lights out. Headlights out.

    What I have done.

    Changed the Headlight switch didnt work.
    Fixed the parking and brake lights that was the red wire in the engine compartment that leads into the fuse box on the firewall. It was broke somewhere behind the motor itself probably due to heat of the engine or corrosion.

    My problem is I can find the wire that operates the power from the battery to the fuse box. Does anyone know which one it is. If you know where I can get a freebie diagram that would be great but if not maybe someone can tell me the color of the wire and where it comes from and where it goes too.

    Also I am considering hooking up my amber light to a switch I have a three prong toggle but should I run it right off the battery or jump it off of some other power source. Any suggestions. It used to have a cigarrette lighter type adapter on it but I want to be able to toggle it with ease instead of jerking it in and out of the lighter.
  2. snowcan

    snowcan Member
    Messages: 52

    You have more than one problem. The first thing you need for the headlights and park lights is a test light.Make sure the fuses are good for the respective circuits then check for power going into the headlight switch, I'm not sure but it should be an orange wire, thicker than the rest (on the headlight switch plug). If you don't have power going in,trace that wire first. You can also feed power from the circuit marked "bat" on the fuse box to the headlight connector (using a jumper wire) and see if you get lights, you will have to try each circuit individually, if you get lights, then you know for sure you have a power input problem to the switch.Don't jump the black wire (ground). Cigarette lighters shorting out is a common problem, if the fuse for the lighter circuit is blown, check the condition of the lighter socket. Your warning lamps should use a separate power source, in other words, make a specific fused circuit from the battery or battery outlet at the fuse box. Dude, I am just scratching the surface here but this is where to start, if you need a diagram I can e mail you one. Hope this novel helps.....later
  3. MickiRig1

    MickiRig1 PlowSite Veteran
    Messages: 3,617

    You can look at manuals at a bigger library( main county/bigger city branch ). Most times you have to go to the desk and they have to pull them out of storage if they are not on the shelf. There are big plot books that show where wires run and where connectors are. On your GM you may have fuse able links burned. This can be why you have no power to circuits that should be hot all the time. Take a legal pad to the library and take notes draw pictures if need be. If you separate connectors in the wire harness make sure you put dielectric grease in them to protect from water & crud. Most headlight circuits are protected with automatic reset breakers that rarely go bad. Look for green powder on the wires a lot of times this is the only clue that the wire is corroded inside. Check and clean all the black ground wire connections you can find coat with the dielectric grease.
  4. yzf1000_rider

    yzf1000_rider Senior Member
    Messages: 147

    you can go to your local libray and they should subscribe to a company called alldata. com and they have the diagram in that for you. just ask the librarian for some help.
  5. MickiRig1

    MickiRig1 PlowSite Veteran
    Messages: 3,617

    Somewhere on the wiring page will be the key for the aberrations of the wire colors.
    like: Brn / org will be brown with orange stripe. Fuseable links will have a color for it's amp value. They look like bugle's in the wire that may be over wrapped in tape or shrink tubing..
    You might have the same wires in the same wire loom leading to and coming from the component.
    Like the neutral switch will be blue / red, you would have 2 blue / red wires in the section of wires,one leads to it, the other comes back from it.
  6. welded wrenches

    welded wrenches Senior Member
    Messages: 177

    k10 wiring help

    hi.there is a big red wire abot 10AWG with a eyelit at the starter solinoid.that goes to the fuse block.ok just above the starter about 4 to7 inches is a a fuseable link.Also both headlites have to have there separate ground wire (black) that bolts to core support just above headlites usind a half inch wrench.Also check your dimmer switch alot these malfunction.DASH LITES have a main harness up behind the and between the speedo and fuel gauge these snap in to place also check the the wire harness connection attached to steerig column just above the brake pedal this is a flat plug with about 9 wires.especially if your is a 1981 and newer the dimmer switch is is on the turn signal lever.ALSO the engine compartment side of fuse block unbolts with a 10 MM socket and will separate in 2 pieces one half is for the engine do dads, and the the other half is for headlites and turnsignals and horn and wiper/washers. Also info help at chuckschevypages.com or coloradok5.com