Strange guitar pickup behaviour

[plithner]

Hello,

<This post might be off topic, but I'm hoping that you experts might have a clue what my pickup related problem is>

I have an old Ibanez (Roadstar RS530), on which one of the original pickups had been desoldered and replaced with another one. I wanted to put back the original again, and since I had it lying around, I went on and did that.

When finished, I tried it out, but the pickup only produced a very low sound. However, I realised that if I played the strings fairly hard (and specifically the bass strings) the pickup came back to life after producing a "broken" sort of distorted sound for a short while. After this, I could play in a normal way, and get normal sound from it. However, as soon as I switched to the other pickup (the neck pickup) and back, it was dead again.

I have reproduced this several times, and I think I can say with reasonable certainty that it is not a loose contact (still, I'm not a soldering expert by any means, so I could be wrong).

The pickups are Ibanez IBZ (https://ibanez.fandom.com/wiki/Other_Ibanez_pickups#IBZ) which are coil-split passive pickups.

Any ideas what could be going on here?

Thanks in advance!

[nickb]

If you have an ohmmeter, check the DC resistance of the pickup while tapping it. I suspect it has a coil with a break and vibration is causing it to make and break contact.

[rjb]

Funky toggle switch contact?

[big_teee]

The way to figure it out, is with a guitar cord and ohm meter.
Plug the cord into the guitar and turn the volume pot all the way up, or on.
Read the resistance from the tip to the sleeve of the cord.
It should read whatever the Pickup DCR is. (Depending on pickup type 3.5K-10K)
Then flip the switch back and forth and try to change it?
You should be able to see big difference in readings, when good vs bad sounding.
T

[plithner]

Thank you so much for all your helpful feedback!

Before trying out any of the proposals, I reversed cables on the pickup switch so that the neck pickup was selected when the switch was in the down position and vice versa. This to try to confirm if the pickup was actually broken.

After this, both pickups worked perfectly :-) . I think that there must have been a funky soldering on the switch after all... You learn something every day!

[rjb]

Tah-dah.