wiring harness smoked

So this morning my as I tried to start the truck with my solenoid, I noticed the wiring harness was smoking. It looks like the connector there has melted together and caused a short.

Question- Can I cut this connector out and butt splice everything? I assume all the wire colors are the same on each side of the union. If not then I would need both sides of the harness, and i can only imagine the trouble and cost of getting that.

That's a VERY common meltdown point in the harness.

All the current that feeds the glowplug relay goes through those two yellow wires. On my '87 I ran a 4 AWG cable directly from the feed side of the relay to the battery side terminal on the starter relay on the fender.

As long as the other wires in the connector are good, just bypass the two yellow wires with a big cable and you should be OK...

ok. Well the problem is that the connector is stuck together and I dont know what else has been shorted out besides those yellow wires, if indeed that is the problem

And is the feed side of the relay the side that is always hot?

On the glowplug relay you will connect to the same terminal the two yellow wires are hooked to. Seems like its a 1/4" stud on the top of the relay.

On the starter relay you will hook up to the same stud as the big red feed cable from the battery (IIRC, looking down on it from the top, leaning over the fender, it's the one on the right.)

I used 4 AWG automotive grade cable, and a 1/4" single hole lug on the GP side, and a 3/8" single hole lug on the starter relay side.

http://www.grainger.com/Grainger/THOMAS-BETTS-1-Hole-Short-Barrel-Lug-3LL42?Pid=search

http://www.grainger.com/Grainger/THOMAS-BETTS-1-Hole-Short-Barrel-Lug-3LL62?Pid=search

BUT, beware the 4 awg cable is pricey and a BIT over the top... 6 AWG would probably have worked too...

I think the size on the relay is 5/16" instead of 1/4".

Thanks sparky. Well looks like I am wiring this weekend. I also have a broken ignition and will convert completely over to toggle switches to run the truck. I will start a new thread for that.

gatorman21218 said:

Thanks sparky. Well looks like I am wiring this weekend. I also have a broken ignition and will convert completely over to toggle switches to run the truck. I will start a new thread for that.

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For the starter switch, use a momentary toggle switch or a momentary push button switch. Run 1 wire direct from the battery with an inline fuse (15 amp) at the battery, connect that wire to one side of the switch, the other wire connected to the switch, run that wire to the start solenoid on the fender where you take the original start wire off. When you turn the key switch on that will power the fuel solenoid on the IP and GP controller.

For the melted connector, just cut the yellow wires off it and splice together. Leave the connector alone, never have to disconnet it unless you pull the engine.

The key switch prolly has a broken rod or bad switch at the end of the rod .

About that main engine wiring harness plug.. They melt at that yellow dual wire connecter end. Thats the power feed to the glow plug controler. Just cut off the melted end and pull apart the plug. Apply some die electric grease after cleaning it out with contact cleaner thats harmeless to plastic... any fake *** auto parts store sells both of these. As posted... Replace the two yellow wires directly from the solenoid to the controller. Some like to install a fuse box... Others don't... Its best to have some kind of fuse just incase the controller craps out on you. The wireing harness plug thats melted will be fine for the rest of the wires... Look closely at the tiny electrical fittings in the plug that carry all the amps to the controller... You willl find out why these burn up.... When they are clean they can barely carry enough amps.. any corrosion and they heat up and melt..... Lots of under hood wireing fires start here....I used some red speaker wire from an audio installation shop. Its got plenty of wires in the 4 g. wire or cable... And carrys more amps too. Easy to handle around differant items when tugging it thru the engine compartment....

ok good advice. What size fuse should be used?

also there is another wire thats burnt out in the harness that runs behind the passenger battery. by burnt out I mean an inch or two of it is missing I will repair that one as well.

Is there any place that has a color coded wiring guide? I have the factory phone book but it fails to mention any colors of specific wires

Unless you come directly from the battery to the glow plug controller and hook on the starter solenoid it's useless to fuse that wire because the battery feed to there has fuseible links feeding it there. Wire directly from the battery thru a 50 Amp in line Maxi Fuse.

also there is another wire thats burnt out in the harness that runs behind the passenger battery. by burnt out I mean an inch or two of it is missing I will repair that one as well.

That wire may be one of the fuseible link wires. Don't replace it with any wire except fuseible link wire, obtainable at auto parts stores. Wire comes in alot of different sizes.

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