Originally Posted by Que89YJ
I think you are measuring the voltage wrong. Recheck your voltage with the sending unit unplugged. You have the ground that is common a supply for the fuel pump power and the fuel guage line. With the resistance of the sending unit you will see less then 12 volts but if you read across the plug to ground you should see the 12 vdc.
I read the Ohm resistance value of the sender unit itself and it tested to spec. I am measuring actual supply voltage from the source (tan wire) to ground (black wire) at the plug with the sending unit unplugged and I get 7.8V DC. There must be something wrong with the gauge then. Thanks for the reply.