Confused about this 4PDT push/pull diagram


Junior Member
I finished wiring my guitar yesterday. I have a 4PDT on/on/on pickup selector switch, a normal 500k volume pot and a push/pull 500k tone pot to drive 2 DiMarzio PAF 36th anniversary pickups. I used this wiring diagram from DiMarzio:

The way I understood this diagram is that when the switch is in the middle position, it is using the pickups together in split mode, and according to the tone pot's push/pull state, the inner or outer coils are used.

However, I noticed that when I pull the tone pot, the switch is defeated. I get both pickups sounding but toggling the switch does nothing. I need to push the tone pot back to down position to get the switch to work like normal again.

My question is, did I make an error in my wiring, or is this the expected behavior according to the schematics?