I've been trying to track down a problem in my indication. I'm reading only 8 volts, the fuel gauge reads empty, sometimes half, the temp never moves beyond 40 and the oil pressure is pegged weather or not the car is off or on. I took the cluster out and all the contact points on the ribbon panel were quite green. I cleaned them up and it seemed to help with the volts. However the rest of it is all wonky. Do the long #6 screws on the back bring power down from the ribbon panel to the gauges themselves? They are quite corroded themselves. This must be a problem in that panel as all my gauges are affected. Speedo and Tach seem to be working though.

 

Turns out it was really bad corrosion on the laminated ribbon panel. Sanded all the contacts and removed and cleaned up all the screws. There was 260 ohms of resistance on the ground runs. Pretty much 0 now. Works perfectly again.

 

I always feels great to find it's a simple problem...and appreciated by others when a resolution is put in the posting. Nice work!