All my gauges are suddenly non functional except the ammeter . The Constant voltage resistor reads only 2.5 to 2 volts across the terminals . I thought it should read higher (6 to 7 volts)Any thoughts. All were working well until today.

Help:

Dallas

 

The ICVR should be 6 volts. I recommend an electronic one. There is an eBay seller that has them or you can make your own.

The replacement type ones are not good at all. I have had 3 of them over the years and the original one is better.