Wiring Schematics
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Wiring Schematics
So after reading multiple posts on this forum for a wacky tachometer then not working I'm assuming it's a grounding issue is there schematics for the placement of all these grounds I'm mainly after the dash grounds. The truck I'm working on is a 1994/7.3 IDI/
Dad said when he hits the dash the tachometer would normally got back to normal running as it is right now full throttle in park I get 500 RPM's if I'm lucky yet earlier yesterday just pushing on throttle I had 2000 RPMS so after all checking and double checking the ground issue sounds to me the problem, And yes the Tach sensor is brand new
Dad said when he hits the dash the tachometer would normally got back to normal running as it is right now full throttle in park I get 500 RPM's if I'm lucky yet earlier yesterday just pushing on throttle I had 2000 RPMS so after all checking and double checking the ground issue sounds to me the problem, And yes the Tach sensor is brand new
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From: Virginia
It can be aggravating hunting all the grounds down unless you have the very nice and well documented schematics from the factory. If they have them in stock, you can get them from Service Manuals, Owner Manuals, Wiring Diagrams, Service Bulletins - Helm Incorporated.
Instead of doing that, I just run new grounds with my own wire. You might have to take the dash apart, and take a pencil eraser and clean all the copper connections on the circuit board. And there will be one ground from the plug going somewhere under the dash. After that, you can run your own ground wire from the firewall to the engine block, and from the frame to the battery neg or the engine block, etc.
Instead of doing that, I just run new grounds with my own wire. You might have to take the dash apart, and take a pencil eraser and clean all the copper connections on the circuit board. And there will be one ground from the plug going somewhere under the dash. After that, you can run your own ground wire from the firewall to the engine block, and from the frame to the battery neg or the engine block, etc.
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Well m I ran a scanner on the truck found out it was a TPS out of position. I took it for a drive ,drove like a dream, shifted good blah,blah,blah right? Well the in-law took it for a drive today and the damn thing didn't make out of the drive not 500 yards and the tack went to zero and the O/D started flashing the only different thing he did that I didn't do he says he put the tilt steering well all the way down and I had it all the way up, so any ways he hit the steering wheel hard in a pissed off manor and everything came back to life. So I got home ran the another scan on her and it came out clean.
Is there something that comes to your mind? Hmmm still looking for that loose wire
Is there something that comes to your mind? Hmmm still looking for that loose wire
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Joined: Nov 2003
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From: Nutter Fort, WV
That sure sounds lie a broken ground somewhere under the dash.
If you get under there with a test light, lots of the metal bracketry is not grounded.
That makes grounds such a big issue.
It was way to simple in the old days, metal everything, everything grounded through the next piece.
If you get under there with a test light, lots of the metal bracketry is not grounded.
That makes grounds such a big issue.
It was way to simple in the old days, metal everything, everything grounded through the next piece.
Lead Driver
Joined: Dec 2006
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From: So. Jersey
I know the O/D switch in the end of the shifters if grounded out will cause havoc. They will rub through the insulation where it crosses over the collapsible column. It's 2 little wires wrapped together. Take the shroud off to check it.
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My research as of today I removed the gear shift and the insulation around the wires (mine has 3 wires) I found 2 different areas where there are burn marks probably had pin holes. I'm going to smear some liquid electrical tape on them well see. I'll still be checking other areas tomorrow.
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Well m I ran a scanner on the truck found out it was a TPS out of position.
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PLC7.3 it could have been that case no doubt but when the scanner said default detected and I moved the sensor to correct position it says no fault but as a conclusion of my wiring issues I found 4 open wires in the steering column area someone had tapped into the existing wires for what looks like a remote starter or maybe an alarm at one time but the old man never has used one as long as I remember him having this truck anyways I redid all the exposed joints/connectors and the gear shift wires were exposed to very tedious work there but seems to be working now 'bout time well see for how long. Thanks folks once again you all help me. Hopefully one time in the future I can be of help/. Now it's time to go fishing the Steelies are running the river
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PLC7.3 it could have been that case no doubt but when the scanner said default detected and I moved the sensor to correct position it says no fault but as a conclusion of my wiring issues I found 4 open wires in the steering column area someone had tapped into the existing wires for what looks like a remote starter or maybe an alarm at one time but the old man never has used one as long as I remember him having this truck anyways I redid all the exposed joints/connectors and the gear shift wires were exposed to very tedious work there but seems to be working now 'bout time well see for how long. Thanks folks once again you all help me. Hopefully one time in the future I can be of help/. Now it's time to go fishing the Steelies are running the river
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