P-Rails: pickups are out of phase with each other. Please help?

[Nekko]

I have a problem with my P-Rails and and their fancy-pants wiring. I used the "2 P-Rails 2 Volume, 2 Tone, 3 Way 2 push/pull (option #2)" wiring diagram and the pickups are out of phase with each other. I double-checked my wiring and the push-pulls are working perfectly to give the rail/P90/series/parallel sounds from each pickup individually, but when I put the 3-way switch in the middle position with both volumes at 10 the output drops to almost nothing and the tone is thin (if you turn up the gain enough to hear anything) regardless of the push-pull settings. When I roll down either volume from 10 towards 0 the signal goes up then down. Classic pickups out of phase with each other behavior. The pickups were purchased as a set and they have the correct part #s for the bridge and neck pups, so it seems like a factory problem. Either the colored leads got put on wrong or one of the magnets is reversed. I haven't had a chance to check the polarity of the magnets but that's next on my list. Inquiry with SD customer service has no response as of yet.

How in the world do I go about fixing this? Normally switching phase would be easy, but with the coil switching I'm having a hard time to figure out what wires would need to be swapped. I suspect that swapping the roles of the green/black wires from ground/hot to hot/ground and swapping the white/red would fix phasing and keep the coil cuts correct, but I would love to have another eye on the circuit.

[jeremy]

welcome to the forum!

can you tell if they are electrically out of phase or magnetically?

[frankfalbo]

If you just want to get them up and working until customer service responds, choose one pickup and swap red for green, and white for black. This will flip phase of each coil of that pickup and maintain the coil split locations.

But CS should work with you to determine which pickup was wired or polarized incorrectly and rectify the situation.

[Nekko]

It's been busy. I'll try to measure the magnet polarity tonight.

[Nekko]

welcome to the forum!

can you tell if they are electrically out of phase or magnetically?

It's a little hard to tell with a compass needle, but it appears that the P90 is south (ie, attracts the north point of the compass) at the top on the bridge and north at the top on the neck, so they are reverse polarity as they should be. It must be that they aren't reverse wound.

If I can make the time I'll do the swaps that Frank specified this weekend and see if it fixes things.

[Nekko]

I finally got around to swapping the wires For one pickup by Frank's prescription and now everything seems good. The weird phasing and volume stuff is gone and the middle position has significantly reduced hum when using either split setting. Based on this it appears that one of my pickups had both coils wound incorrectly or the leads put on backwards. I'm going to give CS an FYI so they have the data point for quality control. Big thanks to Frank for exactly the answer i needed!