Fuel gauge

[philliplancaster]

OK need some help. My fuel gauge doesn't work nor ever has since I bought the truck. I pulled the electrical gauge plug on top of tank and ran a test light on all 4 wires. Gauge never moved and the light never lit. So, now what should I do?

I've read to check the ground wire at tank. Where is this elusive ground wire at? All I see is the electrical connection in factory harness and two fuel lines. I'm missing something somewhere.

 

[Greenleaf]

If you have no power going to/at the plug connector, then a ground wire at the tank won't help any. Did you ground the lead of siad test lamp to a known good ground?



I have not heard of a ground wire at the tank.

 

[cerberusiam]

IIRC, 2 of those wires are Low Fuel light and the other 2 are the gauge. The float component is just a big rheostat that will return voltage to the gauge and cause it to set wherever it needs.



You should have power on 2 of the wires. Make sure you have a good known ground first then check again.

 

[philliplancaster]

Ground is good. Is the fuel gauge on a fuse? I've checked all fuses under the steering wheel but haven't checked anything under hood. All other gauges work. I'm going to trace the wires to wherever this weekend. Just looking for some tips before I tear into the thing. Also, is there a way to test the float by hooking up power somehow at the tank?

 

[Greenleaf]

The float would be tested with an Ohm meter. It should read low resistance at one end and high at another. I don't have the specs but a similar unit in a school bus has a high reading of 96 ohms.

 

[philliplancaster]

Thank you Greenleaf.