2005 Columbia, fuel gauge problems Need Help!

Hi,
Recently Acquired a 2005 Freightliner columbia class, the needle for the fuel is not showing anything.
Here is the steps i took to quickly check this...
1. With ignition on all gauges on dash complete self test (move freely from left to right and back)
2. i tried measuring resistance to the plug that goes to the fuel sender, i didnt see a sign of an open circuit hence no broken wires from dash to fuel sender (i suppose)
3. tried to short the plug to fuel sender = no result
4. tried feeding 9v to fuel sender plug = no movement on gauge in dash

Didnt have much time ot do anything else, and i really want to be on the right track here. Does anyone know the functionning of this system? How does it exactly operate?

 

The fuel sending unit is actually a variable resistor. The float movers up and down with the fuel level which moves the resistor. The gage is just reading the resistance. Most times the float is stuck and is not moving. You should be able to remove the float from the fuel tank and watch your gage as you move the float.

 

come on now this is such a non issue...my pete's fuel gauge has never worked never had a problem...everytime you top off just reset your tripometer you should know about how many miles you can get to a fill up...

 

thanks musicmaker, i like your response better, but my question was after all i did why didnt it move or react when i shorted it and what not???

 

The gage needs a resistance to work, it doesnt go from 0 ohms, its likely that either the wires have a bad connection at the screws of the sensor or the float is not moving.

 

First off do not power the gauge wiring use a multimeter, and check the resistance to ground on the ground wire then ground out the wire to the center post on the sender and the gauge should go to full. Clean off your fifth wheel disconnect tool and with a flash light look for the gauge float and rod, lift it up and see if the float is on and what the gauge does. The floats do come off.

 

Experience with that model leads me to say its a 90% chance you need a new sending unit. Rare that the gauge has died. And its only 5 screws to pull it out and check gauge operation through its swing. And then throw it away and install a new one.

 

I had to do this before. not hard & not expensive.

 

can you give me some help with the sending unit issue also my gauge is stuck to the full position ive change the sending unit and the fuel gauge not working need some help

 

I have same problem on Columbia, fuel gauge not working

i connected to new cluster and nothing
connected to new sender and nothing

in mu case form time to time i got some readings and movement from gauge but after few second drops down or not read accurate.
Doing as LandShark
my advice
suggesting on bad wires or connection somewhere. no time to mess around.