Wiring gone wrong

[bounty32956]

My friend encountered a problem with his bass where the bottom two strings (e and a) were sounding fine, the D string sounded 50% quieter and the G string sounded like it was muted by something. I took the bass to take a look at it, and by the time i plugged it in my PC and booster Guitar Rig, nothing worked! There was buzzing but there was no response from the pickups at all.

So I opened it up and this is what I see:

The red and black wires on the far left are just sticking out not connected to anything. I'm holing in my hand the black wire with a cap that is also not connected to anything (I suspect they go on the far right pot). The far right pot has nothing connected to it.

This is the far left pot:

And this is the on in the middle:

I don't really understand the logic of this wiring at all, there is no wire that goes from pot 1 to pot 2 (on the actual pots) so I tried soldering a loose wire (not the one with the cap) from pot #2 to pot #1 but it did nothing. Also, turning the pot on the far left makes the pot on the inside turn as well, and turning the pot in the middle doesn't make it move on the inside. What's with that?

I hope somebody can help me. Thank you in advance

 

[LoveThatBass]

What type of pickups are on this bass? Jazz pickup configuration? P pickup configuration? or other? I take it does have two pickups right Or just a P style pickup? looks like controls are 2 volume controls and one tone control in the middle

 

[spiritbass]

If you can read wiring diagrams, look up a jazz bass diagram and wire it like that. If you can't solder, or don't know someone who does, take it to a tech. It shouldn't be an expensive repair...

 

[LoveThatBass]

If you can read wiring diagrams, look up a jazz bass diagram and wire it like that. If you can't solder, or don't know someone who does, take it to a tech. It shouldn't be an expensive repair...

In addition to this I would recommend replacing all pots as this is one of the junkiest jobs I have seen and will likely continue to cause some issues even if wired correctly. Cold solder joints and overheating the pots are problematic

 

[dwizum]

I'll second the suggestion to just start over. You need three pots and a cap, and a foot or two of wire. That's about $5 in parts, maybe $10-15 if you don't shop carefully. Ten minutes of soldering and everything will be new, neat, clean, and functional.

 

[bounty32956]

What type of pickups are on this bass? Jazz pickup configuration? P pickup configuration? or other? I take it does have two pickups right Or just a P style pickup? looks like controls are 2 volume controls and one tone control in the middle

I forgot to mention its a PJ bass. I dont even know what the knobs do but I assumed the two on the right are tone knobs because they have the cap idk.

I'll most likely start over from scratch... thanks

 

[LoveThatBass]

I forgot to mention its a PJ bass. I dont even know what the knobs do but I assumed the two on the right are tone knobs because they have the cap idk.

I'll most likely start over from scratch... thanks

A PJ will be 2 volumes (one for each pickup) and one tone. The cap that is on the wires, does that go to the bridge pickup? Not likely to have 2 tone controls and one volume. I suspect someone added that cap on pickup wires to darken the sound. If so I would remove it. Can you see it's value? If so tell me exactly what it say’s on it. Ok?

About your original issue of E and A being ok but D and G lower in volume. That would most likely be the lower half of the P pickup under the D and G. If you find that is the culprit you probably need to put a new P Pickup in it. Before you change it, have you tried raising that half?

 

[bounty32956]

The cap on the far left pot reads 2A473J, it's the green pillowy one.

Yeah, it's probably the lower P pickup. However now I'm faced with the problem of getting no output whatsoever, from any pickup.

 

[bounty32956]

I've just opened the pickup side up and noticed that the lower pickup wasn't wired at all and that the upper one had only the red wire soldered. How the hell did this bass ever work in the first place??

EDIT: I should note these aren't standard pickups that I've found in diagrams. They both have their own Red and Black wire. The red wire of the upper pickup is soldered to the terminal on the far left pot and that's about it, the rest is not wired anywhere. Trying to find info on how to wire them when they have two separate sets of wires.

 

[jamro217]

Welcome to TB. Yeah, get rid of that mess and start over. For reference, the pot closest to the neck should be the volume for the P pickup, the middle one is the volume for the J and bottom one is master tone. Let us know how you make out.

 

[LoveThatBass]

What are the colors of the lower pickup?

 

[LoveThatBass]

Yeah, it is pretty weird how it ever worked

You said the Red on the upper pickup is connected. The other wire on the upper pickup should connect to the lower pickup and the last wire from the lower pickup should go to ground. Thing is need to know the colors of the lower pickup to determine which goes to upper pickup and which goes to ground

 

[LoveThatBass]

The cap on the far left pot reads 2A473J, it's the green pillowy one.

Yeah, it's probably the lower P pickup. However now I'm faced with the problem of getting no output whatsoever, from any pickup.

Yeah that is typical .047uf tone cap but what is on middle Volume pot? I am guessing it is a treble bleed but if so it should be really small?

The bridge pickup volume with that cap on it (that I thought was a tone pot because of the cap) goes to that middle pot and the neck P pickup to the one on the right side. I am thinking the wires were barely hanging on to the pot and just vibration of moving it around cause them to totally break off. Whoever soldering them on must have nicked the wires when stripping and eventually broke

 

[bounty32956]

Yeah, it is pretty weird how it ever worked

You said the Red on the upper pickup is connected. The other wire on the upper pickup should connect to the lower pickup and the last wire from the lower pickup should go to ground. Thing is need to know the colors of the lower pickup to determine which goes to upper pickup and which goes to ground

The lower pickup also has its own black and red wires Should I solder together the black wires of the two pickups and then ground the red wire from the lower one?

The cap on the middle pot looks exactly like the one on the far right pot, except I can't read the number, but I'm convinced they're the same.

 

[LoveThatBass]

No, black from upper half to red of lower half and the black on lower half to ground
They are wired in series (similar to two batteries in series)

Let's hope once correctly wired both halves of the P will work properly

 

[bounty32956]

Oh I get it Thanks, I'll do so asap.

 

[LoveThatBass]

Once you have both halves in series you should only have 2 wires: Red from top half and Black from Bottom half that then connect to the far right pot (black to pot case red to center wiper) then the outer non grounded lug of both volumes goes to the tone pot and out to the output jack. all pot's case grounds need to connect together and go to the output jack's ground lug.
Try not to over heat the pots. I use either a small alligator clip or surgical hemostat (thin silver clamping pliers) on each term I want to solder to. clamp it close to the pot on the terminal you are soldering. It is imperative you do not over heat the pot or it will be damaged. Do not leave iron on pot over couple or three seconds. I will sometimes use pair of pliers to heat sink the case to cool it faster after soldering to it.

 

[LoveThatBass]

added to the above post

Hope you have a good Jazz bass wiring diagram to go by for this bass. Even though it is a PJ it wires like two J pickups on a Jazz Bass

 

[bounty32956]

Man you really know your stuff! I did what you told me, (connected the red and the black) and grounded the remaining black wire and the pickup works as intended! Thank a bunch I dare not wire the bridge pickup because I'm not sure if it works at all (there must be a reason for it being disconnected in the first place). Thanks again, you're a life saver.

 

[LoveThatBass]

Man you really know your stuff! I did what you told me, (connected the red and the black) and grounded the remaining black wire and the pickup works as intended! Thank a bunch I dare not wire the bridge pickup because I'm not sure if it works at all (there must be a reason for it being disconnected in the first place). Thanks again, you're a life saver.

Glad I could help.Did you just wire to the original Pots or did you buy new ones? Also, If you have a volt/ohmeter (DVM digital volt meter with Ohms scale on it) You can read across the Bridge pickup wires. Should be anywhere from 4k-11K ohms. If you have a good reading I do not know why not wire it up. After all it is a PJ bass.