I still cant seem to figure out what is wrong with my gauge. I have unplugged both tanks and diverter vavle and still no change in the gauge. It still sits past full. Ive tried making jumper wires and no change whatso ever. I did notice a burnt pin on the diverter valve harness; looks like the red wire. I dont know what it does. Any suggestions?

 

Take a look at this schematic
https://www.ford-trucks.com/forums/a...1&d=1208519515

Check the fuse?? #17 in the under dash panel.
Fuse OK? Then the gage in the dash may have taken a dump.
The burnt read wire is power to the selector valve.

Does your tanks switch from front to rear OK?

 

All fuses check out ok. Cant tell if its switching to rear tank.

 

grounding or shorting problem somewhere maby??