Tone knob repair question

[polvo]

Hello! I'm fixing up a second hand bass and the tone knob is not working. Can anyone help me find out whether it's a wiring issue or a faulty pot that needs replacing?

 

I've taken some photos of the wiring, it looks correct to me but maybe I'm missing something. All the solder connections seem pretty solid.

 

Thank you!

 

 

 

 

 

[rainbowreality]

If you have access to a multimeter you could check the pot in question. One with continuity testing would be even better to check the wiring. Get a schematic for your bass off the tinterweb to check how it should be wired.  The soldering looks like it could be iffy 

 

I can't emphasise how useful a multimeter is, a cheap and cheerful will do the job and be the best investment you'll make (that and a good solder sucker)

https://thepihut.com/products/pocket-autoranging-digital-multimeter

Edited Friday at 16:02 by rainbowreality

[PaulThePlug]

That soldering does not look great!

But love how the pup covers above ground have yellowed...

[itu]

1 hour ago, rainbowreality said:

The soldering looks like it could be iffy 

I can see tin, and components, but the iron has been cold on the table. 

Edited Friday at 14:38 by itu

[rainbowreality]

I'm guessing the circuit is in series so if it was a dodgy solder connection then there wouldn't be any output at all?

[paul_5]

I'd reflow all of that soldering, it looks a bit.... iffy at best.

The passive tone stack on fender style basses isn't in series with the signal, so if the tone control is faulty then it won't alter the output.

[tauzero]

Not just the soldering, it looks like there are stray wisps of copper too. I'd desolder each joint, cut off the end of the wire and re-strip the insulation with not too much wire exposed, make sure all the cores are together and resolder it.

[mcnach]

On 04/07/2025 at 11:05, polvo said:

Hello! I'm fixing up a second hand bass and the tone knob is not working. Can anyone help me find out whether it's a wiring issue or a faulty pot that needs replacing?

 

I've taken some photos of the wiring, it looks correct to me but maybe I'm missing something. All the solder connections seem pretty solid.

 

Thank you!

 

 

 

 

 

 

 

Frankly, I'd redo the wiring from scratch rather than trying to find the specific problem. The soldering looks pretty untrustworthy in general. You'll probably save time by redoing it completely (it doesn't even take that long), and then you'll know it was wired carefully. I'd reuse the pots, unless you have suitable 'known-good' at hand, they can and do fail, but not as often as what bad soldering does.