68 gauge problem

I took my gauge cluster out of my 68 to install a new bezel and when I put it back together it doesn't work. I put the plugs back on and the gauges light up but none of them move. When I first turned the key on it buzzed a couple times as the gauges moved slightly then nothing. I think the fuse may be good since the lights still work. Any ideas out there?

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The lights operate off a different fuse/circuit.

Maybe the Constant Voltage Regulator?



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Well I went to NAPA and purchased a new regulator and same story. The gauges light up but nothing else. I think I have replaced all the fuses for the gauges but do you guys know what fuse runs them and I will replace that one, or at least make sure it is good. Any other ideas??:bang:
Have you checked to see if you have power to the gauge cluster using a meter??

Like posted above, there's only 5 fuses so just check them all.

If theres a short to ground in the gauge cluster wiring, it will burn up the regulator as soon as you apply power. The only way to know if thats what's happening is to open the regulator. Just pry the metal tabs up and pull the cover off.
I have replaced all the fuses but he 2.5 small one because I can't find one at the 6 autoparts stores I have looked at locally. I think that fuse is for the gauge lights and the seem to be fine. I am having a hard time getting the two electrical plugs completely together. It seems like they are engaging, hence lights, but there is a space about 1/16" I can see between them. I have even tried to pull them together with pliers and they won't come together any closer. Do you think this could be the problem?

Have you checked to see if you have power to the gauge cluster using a meter??
How do you do this? Do I hold a - side of the meter to the dash (ground) and the positive to the guage post? Sorry for the basic questions, I am learning as I go.
I'm looking at a wiring diagram now and the gauges aren't powered from a fuse, at least not directly.

They draw power from the voltage regulator mounted with them. The lights pull power from the Blue wire with the Red stripe. The dash voltage regulator is powered via the Black wire with a green stripe.

Check that wire for power using the Multi-Meter; one terminal to chasis ground, the other (red wire) to the wire you need to test. If that wire has power then there's power to the instrument cluster. At this point you should check your ground wire to the cluster. If thats good then check for any gauge posts that are grounded and pull apart the regulator.

If the Black-Green striped wire doesn't have power then let me know, I'll have to trace it farther into the wiring loom...
I can Email you a copy of the wiring diagrams if you'd like...

I tracked the Black-Green striped wire for the voltage regulator, it pulls power from the accessory wire of the ignition switch. It runs through the fuse block on a 14amp fuse. The fuse is the bottom horizontal one on the right side, pg. E4 for anyone with a copy of the diagrams.