Weird electrical problem
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Joined: Feb 2008
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Weird electrical problem
Ok guys, I'm just now getting back to getting the dash and wiring hooked up after my cab swap('89 F350 w/ the 7.3 and C6 2wd) and Ive got a weird problem. First, my dash lights aren't working, but the warning light do. Second, the fuel selector switch seems to be affecting the factory guages, making them go from side to side when I switch it. The headlight pull switch does the same thing. Could this all be related to a ground issue somewhere that I missed or what? Any help is appreciated
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Senior User
Joined: Feb 2008
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I'm not saying its not needed, just hoping someone could explain whats its for. Only thing I can see is if something else is grounded to the block, but nothing seems to be. Either way, i got the problem figured out, was a few loose grounds
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Joined: Jan 2001
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From: Virginia
The main power hog is the starter. So they run the large ground cable to the engine block. Problem is, the engine is mounted in rubber mounts, the tranny has a rubber mount, and the rearend is mounted on the springs, and they have rubber bushings. So you have a good ground to the engine, but nothing to the body or the frame. So they run smaller grounds from the engine block to the body. They will also run a small ground directly from the battery neg to the sheetmetal on the radiator support or inner fender.
Grounding the sheetmetal still does not give a good ground to the frame, because all the body mounts are rubber. So you will see here and there a small ground strap clipped to the body and then to the frame. My truck has one on the passenger side front cab mount. Some of the trucks also had a different large neg cable that had the insulation stripped in one spot with a clamp around it. The clamp is then bolted to the front frame rail and then the large wire continues to the engine block.
Grounding the sheetmetal still does not give a good ground to the frame, because all the body mounts are rubber. So you will see here and there a small ground strap clipped to the body and then to the frame. My truck has one on the passenger side front cab mount. Some of the trucks also had a different large neg cable that had the insulation stripped in one spot with a clamp around it. The clamp is then bolted to the front frame rail and then the large wire continues to the engine block.
