Fuel Gauge Problem

[QQBlue1]

The fuel gauge on my 68 Charger is not reading anything. It has recently been restored and should work fine. In the process of trying to isolate the problem I noticed that when placing a light where the dark blue wire of front harness connects to the rear harness I get a very low light/signal on both sides of the connector. Is it possible I don't have enough current to power that gauge? This wiring rookie will accept any help!

 

[oldbee]

It's possible that you have a bad ground at the fuel tank.It gets it's ground thru the straps and to the body. I ended up drilling a small hole in one of folded-over corners and running sheet metal screw in it with a wire going ove rto body to get a good ground. I believe voltage limiter on back of inst.panel puts less than 12volts; may be why test light is dim.

 

[bigblock]

It pulses voltage in the 5 volt range. Ground the tank then post the results.

 

[PUNKN8R]

The voltage limiter is supplied 12v usually through the center spade then knocks voltage down to a 5v pulse not constant, if you are looking at front of dash(gauges side) the spade on the right side of limiter is the ground terminal and the spade on the left is where the you will get the 5v pulse this 5v pulse also is the voltage that supplies the temperature gauge with power, both the fuel and temperature sending units are read by resistance.

I had similar problem found that it was a grounding issue not at the tank but through the dash itself so I soldered a 14 gauge wire onto the voltage limiter and grounded to dash panel this solved my problem.

Good Luck Man !!!!

 

[QQBlue1]

Oldbee, Bigblock & PUNKN8R, Thanks for responding! I'll apply your suggestions and let you know out it turns out in a couple of days.

 

[QQBlue1]

I cleaned up the ground and the gauge has been working great for the last couple of days. Thanks for the tip and the voltage explanation!

- - - Updated - - -

I cleaned up the ground and the gauge has been working great for the last couple of days. Thanks for the tip and the voltage explanation!

- - - Updated - - -

I cleaned up the ground and the gauge has been working great for the last couple of days. Thanks for the tip and the voltage explanation!