Ultra Jazz Problems

Discussion in 'Pickups & Electronics [BG]' started by Wireking1, Nov 30, 2004.

  1. I have had an Ultra Jazz set installed for about 6 months in my MIM Jazz. Lately I have been experiencing problems with my bridge pickup. The volume does not seem to work. The bridge p/u pot seemed to have very little/no effect both with or without the neck p/u involved. Also, this pot kills the signal altogether when it is cranked to the max. If you back it down a bit then the signal comes back. If you keep turning down the pot it makes almost no change in volume. Basically this thing was acting funny. I thought it was a bad bridge p/u pot from the MIM control plate.

    I decided to purchase a wired Control Plate with the S-1 Switching button from a 2003 (USA) Jazz. I wired the Ultra Jazz p/u and the S-1 switch (series/parallel) works fine. When the switch is depressed the bridge pot is not actice and the neck p/u pot controls all volume. I expected this.

    Oddly enough, when the S-1 (series/parallel) is not engaged the bridge p/u pot acts just like it did before installing the new control plate (with new pots). It still kills the signal when cranked and only alters volume a tiny bit (if at all). This makes me think the issue is not a bad pot.

    Could it be the Pickup itself? Any suggestions?
  2. Lyle Caldwell

    Lyle Caldwell

    Sep 7, 2004
    How are the 4 wires from each pickup configured?
  3. luknfur


    Jan 14, 2004

    if you want to check the pup just get a small allen wrench (or the like), turn volume off on the neck (and down on the amp) and tap on poles/facing of the bridge pup with the volume low. If you get no response even turning the amp and pup volume up, you know you've got a non-working pup.
  4. Black and white wires on both p/u are wired together.

    Red (hot) wires are soldered to the appropriate places on switch and Neck pickup pot post (original leads were white).

    Green (ground)wires are also soldered to appropriate places on switch and pot casing (original ground wires were black).

    Thanks for any help you can give.
  5. I used this method and it appears I have a dead bridge pickup. They are only 6 months old.... any ideas how this happens?
  6. luknfur


    Jan 14, 2004

    actually, I was in a bit of a fog during that writing and that's a check I usually use to see which pup is reading which amp channel.

    You should as easily be able to tell from playing, if you can't hear the bridge pup with the volume up and the neck volume off, it's not working. If it works fine on some settings (ie. switching, whatever) and not others, it's probably not a pup function problem (although may possibly be something with the way it's wired.

    But to verify the problem is likely in the pup, just wire the pup direct to the jack and play it, thus eliminating everything else in the bass besides the pup and jack - as long as cord, amp, and power supply are good. Bit of a hassle maybe but fairly definitive. If you have a meter you can unsolder the pup wires and check continuity and/or DC resistance before resorting to wiring it to the jack.