Voltmeter conversion connection

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cwalker509

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1972 Mexican GT-351
I am having a bit of a problem here with getting my voltmeter conversion working. I had Rocketman do the conversion. I got my dash assembled and installed and am ringing things out. I am using a jumper cable to apply power. It reads 14.4 volts at my truck. The plug to the voltmeter is a separate 2 pin connector. It reads around 13.4V with the ignition on ond 0V when off. The jumper is at the fusible link in the engine compartment so there is about 1V loss which I can live with. I am getting good connection thru the 2 pin harness since I am getting 13.4V at the ring terminals I used at the voltmeter posts WHEN THE RINGS ARE NOT ATTACHED TO THE VOLTMETER POSTS. Now for the really odd thing. When I attach the wires to the posts,  the posts read 2.0V? The voltmeter does not move. I had 3 converted and checked another one and it does not register either. Does anyone have any ideas?

 

midlife

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What was converted to the voltmeter?  Are you saying both posts have BATT voltage before you hook up your wiring?  Are you sure there isn't any pre-existing wiring to the gauge? 

 

Don C

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I would suspect the jumper wire you're using has bad connections, or the wire running from under the hood has bad (high resistance) connections, or the ground you're using under the dash is not a good ground.

 
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cwalker509

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Late follow up to this.  I used a different source for switched power and the problem went away.

 

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