04 f650 dual tank switch over problem

[wilsontowing]

I have a 2004 f650 with the vt365, it has dual 49 gal. tanks the pass, tank registers on the fuel gauge and when it gets low the low fuel light wont come on and it wont switch over to the drivers side that is full, it just decides to run out... Is this a common problem and what does it take to fix, thanks..

[nycpsd]

no experience with f650 but the fuel circuit is simple, there is power being feed to the float in the pass fuel tank, and when the tank runs down the float attached to a switch now sends power to the low fuel light, which in turn sends power to a relay (automatic switch) which will then apply power to the fuel pump on the drivers side and turning off the pass. side. getting to the problem at hand you said you have a problem with the light not coming on so that mean you need to check the wire at the tank for broken or wires that have rubbed through there casing and grounded which would cause the relay not to operate check your wires and as for the gauge showing full or empty that is a different circuit so it should not be affected hope this helps, and don't know the wire colors will see if i can find more info

[pweiler]

I am having the same problem it was the solinoid for the transfer pump/something that activates the transfer/let me know how you make out

[precisiontow]

wilson did solve the problem? I have an 05 f650 and it's doing the same thing,

[Jacek82]

You probably have a bad sending unit in the tank that is full. I had both of my sending units go out over the years.