Hey guys, I just rewired my CIJ Jazzmaster with new single conductor cloth wiring. I put in a new jack, switch, capacitors, and pots in the same process, now I'm stuck trying to diagnose a ground problem. I have the guitar wired exactly like this schematic, except for the pickup grounds are going to the back of my volume pot. I also have a ground going from the input jack to the back of the tone pot, which is missing in the schematic for some reason.

The buzz seems to be related to my tone pot. When the tone pot is up, buzz occurs, when the tone pot is down...quiet. Touching any metal on the guitar or the strings quiets the buzz down. I have a bridge ground wire running from under my bridge and then soldered to the back of the tone pot. I've redone all of my solders twice and I'm still not figuring this one out.

Sorry for the rambling...solder fumes!
It's a pretty abnormally loud buzz. I've wired both the pickups individually to the input jack, no buzz. Then I wired only the bottom circuit (rhythm circuit disconnected) and it buzzes. Next I tried only the top circuit (just rhythm circuit/neck pickup connected), still buzzes.

I just noticed that neither one of my volume pots is functioning correctly, they seem to have the most dropout about midway in their turning radius and then gradually get louder as I turn them to the off position.
You should have stated that. Sounds like you might have gotten defective pots. Did you check the taper with an ohm meter? Analog would be best, but digital would work.
Both should be 1 Meg pots. Volume - audio taper pot is reading 1 Meg, Tone - linear taper pot is reading 850k.
Last edited by wyplash at Nov 30, 2009,
ok, now check the taper. if you have an analog meter, use it.

turn the pots fully counter-clockwise. put one probe on lug 1 and the other probe on lug 2. SLOWLY turn the pot shaft and watch the meter. it should be rising nice and smooth. if it jumps around erradically or drops out at points, the pot is bad.

I'd replace that 850k pot anyway. it's just barely within spec.