Deere 1020 fuel gauge not working

[ppiske]

I have a Deere 1020 that I bought a couple of years ago. The fuel gauge didn't work when I got it- it always went to the full peg with the key turned on despite the less than full tank. I purchased a new sending unit and gauge but cannot figure out what wire goes where. The new gauge and sending unit act the same as the old ones. Unfortunately, it looks like I may not need the new parts. Can someone tell me what wire goes where? The back of the old gauge has three terminals; Ground, +, and G. The new gauge has a fourth terminal that sticks out from the back. No clue what that is for. I have a switched 12V wire and a new wire from the sending unit to the gauge, as well as ground. Any help- much appreciated!

 

[Tx Jim]

+ goes to ign switch,G goes to sender,ground goes to frame

 

[ppiske]

Well, that works...sort of. Now the gauge reads 1/4 tank when full and empty with no fuel in the tank. Any way of adjusting the scale?