I have an old beater guitar that i've been messing around with for a couple years, it started life as an ibanez gax which I then repainted and re drilled for 2 vol, 2 tone and a 3 way. Up until today it just had 1 humbucker in the bridge and a volume. I put some seymore duncans in an old agile guitar i have (too make it ubbbeeeer metalz for teh drop tunage and it sounds great) and moved the passive pickups to the ibanez. I got it all wired up using this diagram from seymore duncan:

It works on the bridge pickup, but not on the neck pickup. the bridge pickup is dead in the middle position, but oddly, if you turn the neck volume down from 10, suddenly it sounds like both pickups are on, but its not strung up right now and its possible i'm hearing the tapping on the neck pickup from the bridge.

I've double checked the wiring, and there are no obvious errors. My wiring job/soldering job isn't professional, all the solder joints look good, but the the wires are... extra long.. so it would be very difficult to tell from a picture if it was wired correctly.

What could I have done that would result in this odd problem.?

For bonus points, there also might be some weird grounding problem.
It sounds to me like your neck pickup is shorted to ground somewhere. Grab your multimeter, and see if you get 0 ohms (or very near to it) between the hot and ground of the neck pickup leads. If so, disconnect the pickup and then test it again. Perhaps you overheated the lead for it and melted through the insulation a bit down the line. This would make sense because, as soon as you roll that volume down, you've disconnected that neck pickup lead some from the bridge, thus shorting out the signal less. Also, pictures always help
^he should be right. my guess is the neck pickup's hot (input on the neck volume pot) is shorted to ground. however, it could be shorting anywhere along that node. including a dead neck pickup (+ and - shorting), or the wire on the input of the neck volume is touching the pot's casing. remember, think all the metal parts (even on the pots or switches) are ground and its bad for any wire to touch them.
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Geniuses! I used stranded wire, and had twisted it, but there was a single strand touching the casing that I didn't see! Thanks so much for your help!