How many wires to PB pickups?

[Petersinc]

Hi there,

This is my first build and first post to the forum, so excuse me if I'm asking an obvious question. I haven't been able to find anything on previous posts to help me.

I've been slowly working on this PBA-4 build and, when I came to try it out, there was no sound when I play through an amplifier. If I tap on the pickups I can hear that, as suggested in the build instructions, but it doesn't play the sound of the strings.

This kit was pre-wired from the factory, but I wonder whether there should be an extra wire to the pickups? You can see from the attached photo that there is a HOT wire coming from the volume pot to the bridge pickup, and a wire connecting the two pickups, but no earth from the neck pickup back to the pot.

The wiring diagram said "Purple wires may not be required if cavities are shielded and Pots are in contact with the shielding" but I can't see any purple wires on the diagram. I initially interpreted that sentence as suggesting the earth return was optional, since I didn't have one of those, but I've never seen a wiring diagram anywhere else without an earth from the second pickup.

So, is there a wire missing from the kit? If so, can I add one myself? I don't really want to pull the pickup apart to get inside to wire something on, but I obviously can't wire to the plastic pickup cover. What would you suggest I do?

Any advice would be greatly appreciated.

Thanks very much,

Peter

[Fretworn]

I’ll leave it up to the wiring gurus to answer your question. But great job on the headstock. That looks great.

[McCreed]

I can't see clearly what's happening with the yellow wire from the pickup to the volume pot (even when zooming in) but it looks like maybe the shield and the conductor are connected together or to to the same lug.

The two should be separate. The centre insulated wire is your positive, and the shield wire is the ground.
There wouldn't be a separate ground wire from the front pickup because it's connected (grounded) directly through the rear pickup.

If it's the factory wiring, and should be correct, but they make mistakes too, so worth double checking.

See if this diagram helps make sense of things:

P-bass Wiring

Also, +1 on the headstock design! Noice!!

[Petersinc]

I can't see clearly what's happening with the yellow wire from the pickup to the volume pot (even when zooming in) but it looks like maybe the shield and the conductor are connected together or to to the same lug.

Thanks gentlemen, you've solved my problem. The issue wasn't that the shield was connected to the same lug as the conductor, but rather that it wasn't connected to anything at all. That wiring diagram looks very similar to the one provided by Pit Bull, and both showed an earth back from the front pickup, but I hadn't realised that was wrapped in with the yellow wire.

I'd seen that there was a wire hanging out from under the yellow plastic, not connected to anything, but hadn't thought to do anything about it. My first idea was to think this had accidentally connected to my copper shielding inside the guitar body, but making sure it was loose didn't fix anything. It wasn't far from there to think of deliberately touching it to the copper and that solved it. As a permanent fix, I'll attach a wire to the shield wire where it comes out from under the yellow cable and will solder that to the earth on the pot. (unless anyone thinks it would be better attached to the copper shielding).

Thanks once again for taking the trouble to reply. Thanks also for the comments on my headstock. The guitar sat for more than a year because I needed to build up courage. Inspiration came from a photo I saw online of a Ruokangas guitar from Finland. My routing wasn't perfect, but I'm pleased with the double level effect.
https://thenorthamericanguitar.com/p...lectric-guitar

Cheers,

Peter

[Simon Barden]

No, definitely attach it to the back of the pot.

You'd be better off attaching the shield wire directly to the pot, even if it means having to de-solder the signal wire, shorten it a bit and re-soldering. Looking at the photo I'd recommend that you do it anyway, as that exposed shield wire could easily move and touch one of the signal wires and short it out. Unless you have any heat-shrink insulation handy, I'd cut the shield really short so that as it leaves the overall cable insulation it is soldered directly to the back of the volume pot, and have a longer length of the inner signal wire that then goes to the volume pot lug.

Note that it will be lead-free solder that the factory used, so use lead-free to re-solder it. Leaded and lead-free don't mix well (or so I've been told).

[Petersinc]

No, definitely attach it to the back of the pot.

You'd be better off attaching the shield wire directly to the pot, even if it means having to de-solder the signal wire, shorten it a bit and re-soldering.

Thanks, will do. Now that I look more carefully I'd say the shield was originally soldered directly there and has parted company over the months while I procrastinated about cutting the headstock.

Peter

[McCreed]

Excellent result!
Glad it was something simple, and glad we could help. I concur with Simon about the re-soldering to the back of the pot and the method he laid out as well.

All the best,
Mick