Me and my dad just took out the gauges on my 65 GT and put white face overlays on them, only my temp. gauge wasn't working when we took them out and we thought that might have been because of the sending unit, other than that all the others were working. But when we put the gauges back on we found out that only the amps and the speedo were working, we tried replacing the voltage regulator but the gauges still aren't working. What could it be?

 

Do the dash lights work?

If not, then you've not got the ground wire from the back of the instrument panel attached to the car ground. It's a black wire that should attach at or near the CVU

 

I hate those cheap damn CVR. You might have bought a bad one. i did the first time.

 

The dash lights are working.

 

Do you know how to test the CVR to see if it's putting out 5V?

 

I don't know how to test. How do you test it.

 

Take a voltmeter (set on >10V range) and place the black lead to a ground. Touch the red lead to the input side of the CVU (the wire that feeds it). With the ignition on ACC, you should see 12V here. Touch the same red lead to theoutput side of the CVU (the lead that runs to the gages) and you should see "roughly" 5V.... the voltage modulating up and down slightly.

 

Where is the CVU located on the car?

Both my fuel and temp are non-functional. I replaced the sending unit for temp and added an aux gauge and I thought maybe the fuel sending unit was bad and I was going to get a new one but now that I know that the two have a common link, I suspect I need to start looking at other things.

 

It's the small retangular box that is bolted to the back of your instrument cluster. One incoming wire from behind the dash, and one outgoing wire that runs to the back of the gages.

 

It measures about 1" x 1.5"