I've noticed this lately about posts about the Fender Jag-Stang, and how many people have messaged me on Youtube about Jag-Stang wiring and told me the pickup in their guitar has a two wire configuration. I'm beginning to think the two different runs of the Jag-Stang have 2 different wiring designs possibly.
The difference is the criss-cross wiring on the bridge pickup selector is just like the Mustang, phase reversal. Essentially it swaps out the hot and ground wires on the pickup to change the pickup's wiring to be in or out of phase with the other pickup. Mustangs originally had both pickups wired to be both in and out of phase. This is designed to work with the Mustang's 2 wire single coil pickups, one wire goes to ground, one goes to the volume pot, and the switch changes which one goes where, and also breaks contact in the center position to prevent the pickup from making any sound at all.
The secondary Jag-Stang wiring diagram is different, it foregoes the original Mustang wiring by making the bridge pickup switch work the same regardless of position. I think they just put positive and negative lines on the same switch to make the guitar easier to wire and to have a direct connection to the switch instead of another wire that has to go to a ground somewhere else. Which I find kind of weird because I recall a magazine article I read when the guitar first came out mentioning that the guitar had a coil tap in the bridge position switch, and my Jag-Stang had almost all the original wiring despite the EMG pickups when I got it, and no brace-line between the contacts on the negative side suggesting a coil tap, as if you had a 4 conductor humbucker, one could connect the normal ground to the ground connection on the switch, and connect the wires that bridge the coils to the center two lugs (where the ground goes for the 2 conductor pickup). However, given mine had EMG's straight from the store I bought it from, god only knows if the previous owner changed pickups twice or more in the guitar's life and modified it to have a coil tap at one point with passive 4 conductor humbucker in the bridge, or if they very well put a 4 conductor pickup into the Jag-Stang from the start.
Who knows, maybe they possibly had a run early on without taps, or changed it later on (CIJ from MIJ factory change mebbe?). I'll never know since offsets are guitars I've with the wiring exposed the least, and most of the ones I"ve seen have had modifications made anyway.
