I recently started this guitar project on my first electric (Yamaha pac 012) replacing the bridge and neck pickup to Seymour Duncan JB and Dimarzio "the cruiser bridge" in the neck, just like Andy Timmons. However when I put it together realized that there was quite a bit of hum when playing with some gain, even when I disconnected the middle stock pickup It is still the same.

I am suspecting it is the ground from the jack input, but I have tried to ground it to the tremolo block, the volume pot (in the video) and even tried to push the bare wire to the bare volume pot (ruling out problems with the solder), but nothing makes a difference. I even tried to connect the bridge pickup directly to the volume pot (ruling out the pickup selector) without any better results.

I also made sure that I re-soldered every ground connection from the 4 conductor wires of the pickups with no luck. I am also aware that Seymour Duncan and Dimarzio uses different color codes on their wires, but I also tried as the diagram suggested, and switched between the green and black wire on the humbucker, still experiencing the same issue. What am I doing wrong here?

Every kind of comment regarding what I might try to fix this is greatly appreciated

Last edited by Johnniz at Nov 3, 2013,
The ground should go to the back of the volume pot.

Things to check.... (1) Do you have the blank terminal of the volume pot grounded to the back of the pot? If you look at your diagram it is the one without any wire going to it.

(2) Do you have a ground wire from your tremolo claw going to the back of the volume pot?

Also I noticed that you are using the lead channel on what I assume is a Bugera based on the look of the switch. If it is anything like my 333xl, that channel will produce more noise than the others just by the nature of the high gain of that channel. I still think you may have a grounding issue though.
pics of gear updated on profile 11/16/09