Danelectro DN 6-12
Wiring / Circuit Logic
Abbreviated Chart
So you don't have to scroll up and down so much:
P'up switch.
Tone knobs.
Volume knobs.
Necks switch

With both p'ups on, the rear p'up's pot output is connected to the output jack but the rear p'up has no ground connection;  But the front p'up's pot output is routed to the rear p'up's ground lead which hooks up both pickups circuits in a series loop to the output jack.

With the front p'up selected On, the switch lifts ground to the rear pickup circuit and connects the front p'up to the output jack.

With the rear p'up selected On, it's pot output is already connected to the output jack, and the switch provides ground for it's p'up and also grounds out / kills the front p'up's pot output.

With both p'ups On, both necks front p'ups are wired in parallel as are the rear p'ups too, and those front / rear parallels are wired to each other in series as explained in the p'ups switching logic shown further below.

Selecting either neck On merely disconnects the hot leads from the other pickup, leaving their ground leads connected to ground.