Join Date: Mar 2002
Location: Austin, TX, USA
Re: Instrument gauges not working
Take a digital volt meter and measure from the battery negative terminal to the dash panel ground. You'll probably need an extra length of wire to reach, and maybe a helper. Then power up the electrical system and see if you have voltage appearing between the grounds - you should not see any voltage (actually a tiny amount is OK, less than .05 volts or so). If you see voltage you've got a bad ground on the instrument panel, or vehicle chassis. You can do the same trick with the power circuit - measure from the battery (+) to a power wire in the cluster looking for very little if any voltage drop.
68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI