Disconnect the J12 plug from the A9, (float switch module. Hold the P12 side of the wire harness in your hand. Pin one and two should go to FL2. The FL2 is the top float. use a multi meter to find the wires to FL2. One black, one red.
If you do not have faith in someones "fixing" of this switch, I would completely disconnect all the wires and start from scratch. I would pull out the float switch to do that, but you don't have to. Its just easier to do it at a table. Find the two wires to the top float, then the bottom float. This is an easy check. You can also test if the FL switches even work. Something you cant bet money on. You can look at the wire diagram in the -24 manual you should also have in front of you.
Fix one problem at a time.
