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Author Topic: 2004 Fleetwood Discovery 39s. Fuel gauge not working  (Read 1713 times)


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2004 Fleetwood Discovery 39s. Fuel gauge not working
« on: March 21, 2015, 10:23:14 AM »
I wonder if you can help me with me problem on my 24 volt system concerning the fuel gauge and and or sensor.

I have a 2004 Fleetwood Discovery 39s motorhome diesel pusher. I drove to the fuel station, about 10 miles away from our resort, and filled it up 2 weeks ago. The fuel gauge read full after that time.
    I then drove it back to the resort and did not start it up again until yesterday only to find that the fuel gauge was not working.
  It is reading empty, I know thatís incorrect because we have not driven it that far, just 10 miles since fueling it up.
   What I do notice is that when I turn on the ignition the fuel gauge needle does wiggle a little but thatís it.
 I am thinking a few things, the gauge could be broken, or the fuel sensor is not working properly, or maybe there is a fuse someplace that's blown. I checked all the fuses on the 24 volt system that I could find and they are ok.
Can you possibly give me any information on this problem?
  My wife and I are going on a road trip in 3 weeks ( on April 15 ) and I want to get this taken care of asap.
 Anything you can help me with on this problem I would appreciate it very much.
 I am not as educated in the world of electronics as some folks are but I did work as an HVAC tech for almost 40 years and have a fair understanding of wiring schematics and such. Please, if anyone can help me in any way I would appreciate it
very much.   Thank you David A, Packard

Gary RV_Wizard

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Re: 2004 Fleetwood Discovery 39s. Fuel gauge not working
« Reply #1 on: March 21, 2015, 10:55:47 AM »
First of all, it's not a 24 volt system. Nothing in your Discovery or its Freightliner XC chassis runs on 24v (it's all 12v).

The fuel gauge comes with the chassis from Freigtliner, so a call to FCCC Customer Service with your VIN number will get you some tech help specific to your chassis.  1-800-FTL-HELP (1-800-385-4357)

Generally a fuel gauge is either the sending unit (in the tank), a wire from there to the dash area, or the gauge itself in the cluster. A wire is the most common problem, I think.  There may also be an electronic controller for the dash gauge functions that could be at fault. The nice folks at FCCC can advise on that.
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL


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Re: 2004 Fleetwood Discovery 39s. Fuel gauge not working
« Reply #2 on: March 21, 2015, 02:33:47 PM »
Thank you Gary,
 I looked under the coach at the 90 gallon tank and I think if it's the sending unit that means the tank has to be removed by a service company and then the sending unit replaced. I hope it's not that.
  I will check the wire from the gauge to on the cluster. I would think there would be a reading on the wire if I checked it with a meter.
Thanks for the heads up on my thinking 24 volts instead of 12. I have a lot to learn. I will get back to you and let you know the results of everything. Thanks again for the heads up.  Dave


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Re: 2004 Fleetwood Discovery 39s. Fuel gauge not working
« Reply #3 on: March 23, 2015, 09:48:45 PM »
Most common is a bad fuse.  If you are handy, check the ohms reading in the input to the gauge.  Can be the sender, can be the gauge, can be a ground off the gauge. 
Roger & Paula
Relocated Texans
2002 Coachmen Class C
Enjoying the sunshine and beaches
Port Charlotte, FL