PJ Pickups Head Scratcher

[BassNation]

I finished assembling a Warmoth PJ bass last night, installing a Fender Original P Bass pickup and a Dimarzio Model J, wired in the standard V-V-T configuration. When I plugged in and fired up the amp the bass produced some pleasing sounds until I turned both volumes to full on. "Ah, dang, the pickups are out of phase," was my first thougth. So I opened the control cavity and reversed the Dimarzio Model J's hot and ground wires on the volume pot, thinking, "That will fix it." Plugged in right afterwards, and this time did not get any sound out of the Dimarzio Model J while the P Bass pickup remained working just fine.

Thoughts? Suggestions? Recommendations?

Incidentally, the Model J is a four wire pickup. As instructed by Dimarzio, the black and white wires are tied together, the red wire (hot) is connected to the middle tab on the volume pot and the green (ground) is attached to the back of the pot.

I look forward to reading any and all messages.

[stuonbass]

I've had dead Dimarzios before (no output). Perform continuity test with ohmeter to see if they are any good.

[line6man]

Do you have the shield wire attached to the green lead?

It is possible that maybe the green wire is in some way referenced to ground, which would cause it to ground out anything that it connects to.

You could try putting it back the way it was and then inverting the phase on the P pickup instead.

[BassNation]

When I reversed the Model J wires I attached the green to the center post on the volume pot and connected the red to back of the pot for ground. I have not, however, gone pot to pot to pot with ground wire connections as the pots are all touching a grounded copper shield (rear route), which I believe is just like having a metal shield as on a J bass. Perhaps that was a mistake -- I'm not sure. As far as reversing the leads on the P Pickup, I've not tried that but could give that a shot tonight.

[BassNation]

Problem resolved. Discovered a bad solder connection. The Dimarzio Model J leads are now reversed and the pickups are in phase. I'm liking the PJ configuration. The Fender Original P and the Dimarzio Model J are very close in terms of ouput and match up quite well.