Hey I got a 71 f250 a few weeks ago and the voltage gauge just went out. it was not long after i replaced the voltage regulator in the truck. not sure whats up with it. it still lights up like all the rest of the gauges, so theres power going to it, but the dial isn't moving. Any clues what's up? I'm not too farmiliar with aftermarket gages. Shoot, if it was the stock gauge, I'd have that instrument cluster pulled and opened up in no time. Thanks guys. heres the setup that came with the truck. it's the volts in the middle.. http://www.jegs.com/i/Auto-Meter/105/2398/10002/-1

 

It's probably just dead, how do you have it wired up ? I have my volt gauge wired to an accessory wire. Make sure it's got a good ground as well.