Did you add a resistor to the voltage feed to the gauge or a true voltage regulator/reducer aka transistor. If you added a resistor and didn't complete the circuit then both ends of the resistor will read source voltage as the circuit is not complete as the gauge acts like a series resistor to the one you added. Have you checked the gauge with an ohmmeter to make sure it's not open?

Last edited by beltfed; 02/27/2011 4:20 PM.

Six volt guy living in a twelve volt world