We are trying to get the fuel gauge working in my friend's '76 Maverick. So far, I have found that the wires were ripped apart inside the trunk. I did the old trick of connecting them together to see if the fuel gauge would go to full, but it did not. Does anyone have a wireing diagram showing how the fuel gauges is wired from front to back of the car? Bryan decided he likes the older style gauges better with the 120 speedo and silver in the middle, so I brought the '76 Gauge cluster home and am about to swap in a spare set of older style gauges. I'm going to swap the gas gauge also with one that is known to be working. I have tested the sending unit, and it is working fine. What else could make the gas gauge not work?
Jamie, did you do a continuety test to make sure the wire isnt broken down somewhere further towards the car? Just a thought. Dan
If the wire colors are the same as a 72, you should have a black wire (ground) and a yellow with a white tracer wire which goes to one side of the fuel gauge. Make sure your wire is ground. You can check it with a meter or just run another ground wire to the battery terminal for testing purposes. If you ground the yel/w wire, the gauge should deflect to full. If not, its probably the voltage regulator on the back of the instrument cluster. Power feed to the gauge system comes through a black with a light green tracer, wire. It is a resistive wire which knocks the voltage down some. That feeds directly to the cluster. From there it goes to a coil ( probably for noise suppression, and on to the voltage regulator. The other side of the regulator is connected to the other side of the gauge.
I would have done a continuity test, but I wasn't sure which wire is the ground. There is a white wire and a black wire that goes to the sending unit. I think I may have found the problem though. When I took the gauge cluster apart and took the fuel gauge out, one of the studs on the fuel gauge was loose and fell out. A very small string of wire came out with it. I replaced the gauges in the cluster with some spare ones from a '72 or '73 Maverick. If it still don't work, then I'll check all that stuff Dennis. Thanks.
Turned out to be the fuel gauge itself in the cluster was bad. Everything works great now. Now on to getting the cooling system, brakes and all that in order so he can start
