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12v Gauge Problem

thecramp

thecramp

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Hi, i just buy a new 12 V Gauge Cluter, and my problem is that when i plug it the battery and fuel needles are going directely to the maximum value at the right, does it hapened to one of you ?

Thanks
 
mine did that also, but it was the old gauge. tracing it back i found that my sending unit was well... completely gone, thus causing a short circuit or incomplete circuit. I searched this forum and also http://www.oldgmctrucks.com/
discussion boards for fuel gauge or sending unit problems. I wish i would have kept those pages, but i didn't. However there is a few step by step procedures that will pinpoint if the problem is the sending unit, the wire between the sending unit and gauge or the gauge. Also search for a wiring diagram for your truck. Here is a link for mine. http://www.oldgmctrucks.com/photos/GMCWIRE_AllModels.jpg
It is a 52 GMC 3/4 ton, which where originally 6Volt + ground electrical systems. i just followed the diagram, and changed polarity and added a voltage reducer to get my gauge to work with the 12V - ground system I have now.

If I find the pages that I used, I will send you the link. It could very easily be a short in the wire going back to the tank. I found 3 bare spots in mine. :eek:

Best of luck
 
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oki thanks ; it's Strange because everything seems to be ok, i didn't see problem before, my sender unit is new and my gauge too. i 'll try again to examin all wire and plug, i think my ground is good too :-( Thanks , i 'll tell you when i'll find.
 
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Gauge Faults

Please do a search for my older posts on gause testing . I wrote comprehensive step by step directions , do them in the correct order and you'll soon know what's what .

DON'T let the <magic> smoke out of the wires ! :eek:
 
i'll do the research, ok there is maybe a problem with the wiring with the fuel gauge , but what is really strange it's the battery, the needle goes to the maximum, the voltmeter for battery is very simple to plug, but it react as a 6V , the stranger is that it's written 12v on the back! , i don't understand , how can i test if it's really a 6v ? where does the needle should stay in the good position ?

Thanks.
 
O.K. here's the basics :

power to the _left_ most post , other post no connection , the gauge should high side .

Now , ground the rightmost post (the sender side) and the gauge should go to empty .

This and more was in my other post , I'm not trying to shine you on , I'm recovering from a traffic accident.
 
I am going through the same thing right now myself. Figured it was just a bad gauge so I just ordered another before i saw this post. Let me know what you find out also
 
Im sure Nate's post was the one that I found that went though step by step on what to look for and what is wrong. Helped me find what was wrong on mine real quick.

there is really only 3 things, sending unit, wire from sending unit to gauge, or gauge. and make sure you have a good ground.
 
Thanx Wolf !

That's the one , could you maybe please post up a link to it ? .

IIRC it was titled " Fuel Gauge Diagnosis " or similar .

You are correct , there's only a very few things that go wrong ,take your time and ensure good power and perfect grounds to both gauge head and sender , it'll work fine for pennies .
 
Thanx !

That one is close , I am pretty sure a while ago I wrote one that covers everything step by step in one long(ish) post...

If this one gets the job done , well and good .
 
YEP that is the info that I used. by the way thanks nate for posting it!! :D
 
If the line that goes to the sending unit is open, it will read full and in a hurry.
 
... i 'm back , i'll follow the link and test the fuel gauge later, i'm actually concentrate on the 12 v gauge, the problem is the same, i pluged a wire on the body (ground) and an other on a 12v wire, the needle still go the the maximum on the right (if i invert wire it's on the left), i tried to wait a seconde to see and my fuse burned ( can it be a short circuit with 2 wire to plug?). What do you think it can be, i have only 2 wire a ground and a +12v and the gauge, it doesn't work ! crasy no? somebody can send me a picture to see how the needle should be with the 12 volt in the gauge . thank tou much.
 
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You're all Over The Map

And this makes helping you near impossible as you're probably vreating more problems as you jump from one thing to the next .

Now , go get a multi-meter and set the range on 20 Volts DC , see what the voltage is at rest and when the engine is running...
 
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