Electrical short...HELP!!!!
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Electrical short...HELP!!!!
I replaced my glow plug harness and glow plugs. The harness I put on was from an 89 and mine is a 91, both 7.3s. Everything is connected correctly according to the manual and the was the other harness was connected. So, yesterday I went to start it and a bunch of smoke came out from under the hood. I checked it today and found the following problems; one of the fusible links is gone and it appears to have been for awhile, another one is getting hot and is the source of the smoke and the connector where the glow plug harness connects has two burned connectors whoich are the two yellow power wires from the battery. I double and triple checked everything and the new harness is connected correctly. The fusible links are next to the battery on the passenger side and come out of a single yellow wire that is connected to the starter solenoid. I'm totally at a loss on this one. One thing I have noticed is that when I had the old harness and glow plugs the glow plug controller would click multiple times until the wait to start light went out. Since I changed the harness and glow plugs the unit does not click like it did before but I can hear a hum that sounds like it's working. Any help will be appreciated.
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I need a picture of whqt wires go where on the starter relay. I'm trying to figure this out but I'm not having any luck. If anyone can post a picture or even tell me which wires go where that will be a great help.
Thanks
Thanks
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Joined: Nov 2003
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From: Nutter Fort, WV
Back side of the starter relay should have one wire, black I think that goes down to the starter solenoid.
The alternator, glow plugs, battery positive wire and a power wire that goes into the cab all hook on the front terminal.
The only other wire is the trip wire that comes from the key switch to tell it to crank the engine over, it is on the small terminal all alone.
The alternator, glow plugs, battery positive wire and a power wire that goes into the cab all hook on the front terminal.
The only other wire is the trip wire that comes from the key switch to tell it to crank the engine over, it is on the small terminal all alone.
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Thanks Dave. I think I may have found the culprit. The glow plug controller relay has a crack in one side and the small post with the red wire on it doesn't tighten down. Well, it does but the whole post just turns around 360 degrees. Is it possible that the solenoid is bad and shorting out? I have to say I've looked at every wiring diagram and the thing is hooked up right. I do have a fusible link I have to replace now but I haven't tracked down exactly where that wire goes.
Post Fiend
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From: Nutter Fort, WV
The small red wire with a green stripe, that is power from the ignition switch.
If that post is shorting to the glow plug circuit, you can see it is way to small to carry 200 amps.
That would also blow the fusible link from the relay to the cab power wire.
The red wire should be hot when the key is turned to ON.
If that post is shorting to the glow plug circuit, you can see it is way to small to carry 200 amps.
That would also blow the fusible link from the relay to the cab power wire.
The red wire should be hot when the key is turned to ON.
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Thanks everybody. I think I've figured a couple things out. First off I replaced the glow plug control solenoid because it was cracked all the way through. Hooked everything up and still had the problem; "smoke.". I checked the resistance on all wires and all was OK. I unhooked the red wire from the glow plug controller, hokked the connection together and no "smoke." Hooked it back up and smoke. So, I hooked the old glow plug harness up and no problems except the truck won't turn over unless I jump the solenoid. The fried fusible link is causing that I believe. I did the test Dave suggested and there is power to the red wire on the controller. Then it occured to me after reading all the schematics, for at least the 100th time, that PLC7.3 sent me that I may have created my own problem. The glow plug harness came from a truck with a 5 speed and mine is an automatic. What does that have to do with anything? I'm not sure but I think, looking at the schematics, the red wire from the controller goes to the E4OD module which, I believe has something to do with the neutral safety switch. This is just a guess but everything is pointing that way. Now I just need to replace the fusible link and see what happens. Will post more after I get that dones and get the fuel pre-heater leak fixed.
