Help! (JP12 7-String) Tone pot doesn't do anything

[Stillbruch]

SOLVED (JP12 7-String) Tone pot doesn't do anything

Hello everyone

I just got my JP12 7-String. Almost everything works great, but as the title suggests, the tone pot doesn't do anything - and I'm not talking about the coil-splitting with toggle-switch in centre position, that works fine.

I've made two pictures of the electronic stuff - so far, I can't see what's wrong. I've some experience in soldering, and I swap pickups a lot in my other guitars.


About my equipment: I play through the Axe-Fx II (FW 11 Beta) with self-made TS-cables (I tried out multiple cables). All other guitars work perfectly - no issues with my friend's JP7 MD. I've also swapped the 9V-battery.

My question: Is that a common problem or has any of you witnessed that behaviour? Should I contact customer support or get my guitar to a qualified technician? Or does any of you see on the picture what might cause the issue?
Thanks a lot in advance!

PS: I also noticed that if the guitar is played through the Piezo/Mono-jack with the selector switched to Mag only, there is tremendously more high end - a behaviour that didn't show on my friend's JP7 MD.

UPDATE
Problem solved, see http://forums.ernieball.com/music-man-guitars/56862-jp12-7-string-tone-pot-doesnt-do-anything.html#post923060.

 

[DrKev]

If you bought your guitar from a store and your warranty is still valid, bring it back to the store and let them handle it, as they are supposed to do. Otherwise, contact EBMM Customer Service for advice before doing anything else. It should be an easy job for any good guitar tech. If you can handle a soldering iron and a multi meter, you should be able to do it yourself.

 

[Mordimer]

The "electronic stuff" looks a little bit different than in my JP7BFR. Pickup switch PCB is different and there's no PCB on the tone pot in my JP7:

In your pictures I can't see the capacitor between the tone and volume pots - is it soldered on the PCB?
The tone pot won't do anything if there's no that capacitor.

 

[Stillbruch]

The capacitor is soldered on the "back side" of the PCB on picture 2. I'll take the guitar to a local guitar tech today. I bought it in the USA, but I live in Switzerland and I am there now, so there will be some issues with the warranty. But luckily, this is only a small issue.

 

[Stillbruch]

Good news: I just solved the problem. The tone pot works fine now.

I got in touch with Mr. Braman from EBMM customer support. He e-mailed me wiring schematics, and I doubled checked everything and didn't find found anything wrong, but there was one suspicious thing (https://www.dropbox.com/s/6q5usyklsk4fjf8/IMG_2334.jpg). As you can see, the middle terminal of the pot on the bottom of the PCB is soldered, but the left and right ones aren't. I e-mailed him that picture and he told me to solder those too. That was the solution to my problem.

I'd like to thank everyone for helping me out, especially Mr. Braman from EBMM customer support!

 

[DrKev]

A.J. to the rescue again! I'm glad you got it all sorted out.