Fuel Gauge Inop

[Dick Simonis]

All of a sudden my fuel gauge quit and is pegged at full scale.  The coach has just been sitting in the barn since we got back from our last trip and has about 1/2 tank.  It looks like it has three terminals and a spade connector but I can't tell which terminal is which.

An insight would be beneficial.

Thanks
Dick

[Gerald Farris]

Dick,
A fuel gauge reading that is above full means an open circuit, and a below empty reading is a short to ground. If you take the 12 volt wire at the tank sending unit and run it through a variable resistor, you should be able to change the dash gauge reading by changing the resistance. If so, the wiring to the tank and the dash gauge are good, and you have a bad tank unit or an open ground at the tank.

Gerald     

[Paul Meehan]

I had the same issue.  "First" ordered fuel sending unit from BCS.  Did not install the sending unit.  Pulled the dash and tightened the connections on all gauges.  The fuel gauge now works and I have a fuel sending unit when mine actually decides it has had enough.

It is often posted on this forum to NOT throw parts at a problem before it is diagnosed.  I am learning!

[Steve Huber Co-Admin]

Dick,
There are 3 wires going to the fuel gauge.
-Gnd that is daisy-chained to all dash gauges.
-Fuel level from tank
-Ign Pwr to all gauges
If none of the other gauges are acting up, it is the Fuel level signal that is bad. Follow Gerald's instructions.
If other gauges are also acting up, Ign Pwr would be the chief suspect. It is fed from CB27 on the Ignition buss in the electrical bay. Check to see that you have 12v when ign is on.
Steve