'85 P Bass Lyte blend pot replacement question

Discussion in 'Pickups & Electronics [BG]' started by Stephen Simon, Jun 22, 2016.

  1. Stephen Simon

    Stephen Simon

    Jun 22, 2016
    I have an '85 P bass lyte. The stem on one of the pots broke. Under the hood it gets more complicated than I can grasp.
    The pot I'm looking to replace is the only pot that is not wired directly to any type of circuit board. I'm thinking it is a blend pot. On the side of the pot I read "500 K(ohms symbol)A" and directly underneath that, "500 K(ohms symbol)C". Looking down at the pot from the player's view, there are four pots, two pots in two rows. The pot in question is in the row nearest the floor and is the pot on the left.
    I replaced it with a blend pot, (Alpha Blend Pots, 250K-ohm Item # 4137). The result was at the indent the bass produces no sound. The further from the indent one goes the more volume is achieved. The volume is all neck or all bridge depending on which way you turn.
    I'm no stranger to getting things wrong.
    Here's a pic of my handy work, and a diagram I grabbed from the web.
    Any advice would be appreciated.
  2. You wired it backwards. Swap the output and ground.
    walterw likes this.
  3. Stephen Simon

    Stephen Simon

    Jun 22, 2016
    Hey line6man,
    I got it working, thanks to your advice.
    BTW, just bought a Line 6 Lowdown LD300 a few weeks ago. I really like it.
    Thanks so much for your help.
  4. walterw

    walterw Supportive Fender Commercial User

    Feb 20, 2009
    that's what usually happens :)

    for fun, now try the "ungrounded" variation; snip out the ground connections to the blend pot lugs entirely, so you just have the two pickup hots going in, the one wire jumping across diagonally, and the one wire out.

    you should find that the bass now sounds a little clearer and the blending happens much more smoothly.

    (keep the pot case and the pickup grounds themselves grounded, of course.)
    wcriley likes this.