82 sending unit wiring
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From: Denton, TX
82 sending unit wiring
I’ve got a new aftermarket wiring harness with one wire dedicated from gauge to fuel sender. The sending unit has two posts coming out of it. I assume one is for ground and the other goes to the gauge.
is that the case? If so, does it matter which post is the ground and which is for the gauge? There is no label on the sending unit.
is that the case? If so, does it matter which post is the ground and which is for the gauge? There is no label on the sending unit.
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From: Denver Metro Area, CO
Look on the underside of the sending unit; is one wire red and the other black?
Here is from the 1981 EVTM:
Fuel Tank Selector & Gauges - ???Gary's Garagemahal
Here is from the 1981 EVTM:
Fuel Tank Selector & Gauges - ???Gary's Garagemahal
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From: Denton, TX
I don't remember if it had two wires or one coming out of the bottom. I guess I will have to take it out and check. I was hoping to not have to, haha.
Franklin, pardon my ignorance, but does that mean that the insulated post is the gauge wire and the metal to metal is ground?
Franklin, pardon my ignorance, but does that mean that the insulated post is the gauge wire and the metal to metal is ground?
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From: Virginia
I don't remember if it had two wires or one coming out of the bottom. I guess I will have to take it out and check. I was hoping to not have to, haha.
Franklin, pardon my ignorance, but does that mean that the insulated post is the gauge wire and the metal to metal is ground?
Franklin, pardon my ignorance, but does that mean that the insulated post is the gauge wire and the metal to metal is ground?
The sending unit must be grounded or it will not work. All the sending unit is doing is varying the ground of the gauge wire. A quick test of the gauge is to turn the key on, leave the engine off, and then take the sending unit wire and touch it to ground, and then unground it. Each time you do this the gauge will swing full scale back and forth. This works for the temperature and oil pressure gauges also and their respective sensor wires on the engine.
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From: Angier, NC
On our trucks 1 post on the sender is the "hot wire" for the gauge and the other is a ground.
Other makes only have 1 post as the sender is ground thru the mounting lock ring and sender body.
Dave ----
Other makes only have 1 post as the sender is ground thru the mounting lock ring and sender body.
Dave ----
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From: Denton, TX
I took a picture of the posts on the sending unit and cannot tell any difference between the two. Is there any way to tell which is ground and which is "hot" without removing it?
Also, anyone know where I can find push on stud/post connectors that will work? I can use regular connectors, but it looks like the posts are so close together that there isn't enough room for the nuts to fit side by side.
Also, anyone know where I can find push on stud/post connectors that will work? I can use regular connectors, but it looks like the posts are so close together that there isn't enough room for the nuts to fit side by side.
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From: Denton, TX
Okay, Thanks for the information. I'll give it a shot. What will I be looking for with the OHM meter? meaning, which reading will be ground and which would give me hot?
I looked at all the parts stores around and they don't carry any of those connectors. W
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From: Virginia
Take your meter and put it in resistance mode(to read ohms) and then touch the two meter leads together. That is what you want to see when you put one lead on the sending unit metal piece, and the grounded stud. Is this tank empty? You may get a low reading on both studs and if you do, you can turn the tank upside down and take the reading again.
Don't worry, you can't burn anything up. If you get it backwards the gauge will not read correctly, so just swap them around if it doesn't work.
Don't worry, you can't burn anything up. If you get it backwards the gauge will not read correctly, so just swap them around if it doesn't work.
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