1981 Voltmeter
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Joined: Oct 2023
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From: Greeley, CO
1981 Voltmeter
So I replaced my voltmeter with an aftermarket from zip because the old one was dead. Also replaced the PCB and all lights to those gauges. Works good showing 14v when running, but when i turn the headlights on it goes to zero and stays there. Turn them off and it returns to normal operation. I realize they are a big draw, but I would not think that much. Any ideas are greatly appreciated!
Thanks!
Thanks!
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Sounds like your volt gauge isn't grounded correctly and is likely finding a ground through the lighting circuit when it's off. But when the lights are on there is voltage on the line and the guage now can not ground through the light circuit, kinda the way those front side marker lights ground through the front running lights. But that of course is intentional.
Pull that center guage cluster back apart. Triple check the wiring at the volt guage. Triple check the ground!
Pull that center guage cluster back apart. Triple check the wiring at the volt guage. Triple check the ground!
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Joined: Oct 2023
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From: Greeley, CO
Thanks 4-vettes. There is no wiring on this one. Not to the gauge at least. Its got a very primitive PCB on the back of the cluster and gets power and ground through that. I will pull it back out and see what is going on.
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Double check that PCB. Sometimes the tabs get shifted. Perhaps that can happen on a new one, too.
I had a bad connection in one due to a bent pin in the mating connector, so also check that while it's apart.
I had a bad connection in one due to a bent pin in the mating connector, so also check that while it's apart.
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Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
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2024 C3 of the Year Finalist- Modified
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Even a missing or improperly placed fibre washer can do strange things. Check everything closely.
