In this post I will show you a wiring diagram of the neck pickup switch. This is something uncommon, what David Gilmour has got in his signature Stratocaster guitar - Black Strat. It allows him to switch-on the neck pickup, when the selector is connecting only the bridge or the bridge and the middle single-coils. In this way, he can play on the „neck + bridge” pickup configuration, or even on all single-coils together.
The diagram shows only the part of a Stratocaster wiring. Everything, except the neck pickup switch, should be like in common configuration.
My wiring diagram is based on a SPDT on-on mini toggle switch. It will work as "on-off".
The switch needs some extra hole in the pickguard, so drilling can be necessary.
How it works?
It's a quite simple circuit. When the pickup selector is connecting only the bridge, or the bridge and the middle pickup, the signal from the neck p-up has no way to go. If you will use the neck pickup switch, you will connect this single-coil right to the first lug of the volume potentiometer.
It's very simple and can be very useful. The „neck+bridge” pickup configuration is popular in Gibson's guitars and Telecasters. Unfortunately, a typical Stratocaster, with its 5-way selector, hasn't got that option. With this switch, you can reach it.