Some of the center gauges were not working. So I installed a new printed circuit board and bulbs. Now none of the gauges work but the bulbs light up. Plug is installed correctly, tested plug wires and no power but good ground. Fuse is good????: Are the ceramic resisters supposed to be conductive? I used my test gauge and they show conductivity.

 

TJD,

You tested the wire at the gauge connector and have no power, but you have power at the fuse right! The only assumption I can draw up from this is that you have a break in the power feed wires.

The resistors if removed from the gauge should have a resistance between 85-135 ohm's depending on which gauge you are working with. In most cases they will ohm out around 90-100.

Willcox

 

Thank You for your response. I was able to fix my tach by going to your web site. As for the gauges, is there any where I can look up, that shows a way to test the gauges like the tach? The only problem I had installing the new printed circuit was that the clock had a short. It fried the printed circuit lead to it but everything else tests good.

 

Testing the gauges is actually pretty easy. With the key on.

For the temp gauge, remove the wire from the temp sending unit.. If the gauge goes to cold then ground it out.. the gauge should go to hot.

For the Fuel gauge, remove the wire from the sending unit... if the gauge goes to full, then ground it and it should go to empty.

Amp gauge is a little tricky but a quick check is to turn on the blower motor and pull the headlamps on. At this time look for a negative deflection in the gauge.

The oil pressure gauge is exactly like the fuel gauge, remove the wire from the sending unit and it should peg max pressure, ground it out and it should go to empty.

If the gauges all pass these test then you have a working gauge. If it fails these test it is not saying the gauges are bad since there may be a problem in the wires that supply the gauge.

When you turn on the key and I say this 100 times a week.. what is the position of the gauge and do they move at all. If it's a fuel gauge, where is the needle pointing with the key on and the same for the other gauges! A reading will tell you more info about what the problem is.

Is there a step by step.. For the fuel gauge yes and it's on the site. I have not finished the other small gauge helps yet.

to isolate what wire does what on the printed circuit or on the connector I have a picture with each one labeled, but you can usually just follow the wires and tell which pin works which gauge.

I think if I were you, I would verify that you either have power and ground on all the appropriate locations before I tore the car apart. I would verify that the ground I'm using is a good ground too!

Here is a detailed printed circuit schematic that should help you.

Willcox

 

Once again Willcox comes thru. Thank You

 

Joe, would you happen to know how the water temp gauge installs? What I mean is, what nuts go where, and where is that little white block/insulator supposed to be? I keep shorting out and frying water temperature gauges. Thanks.

 

Check this out. Click on supporting documentation.
http://willcoxcorvette.com/repairand...lp.php?hID=284

 

Roger-

I'm getting slow in my old age.. once again you beat me to the picture..

Ernie..

 

Yep, figured it out: http://willcoxcorvette.com/instructi...ions_68-82.jpg

Seems bubba must have had electrical tape on there. I made some plastic washers and all is good. Thanks.

 

Bubba seems to haunt us all from time to time...

Willcox...

 

Yep.

I have a feeling that the original water temp gauge is probably fine. That said, how can I test it. Might make sense to ebay it, seeing as how I replaced it thinking I fried it.