Help! Pickup suddenly thin

[MKR]

I need help regarding my beloved classic player jazzmaster. Plugged it in after sitting in its case for a few weeks and I noticed the bridge pickup is super thin. It lost all of its low end. The pickup works, It's just all treble no bass and quieter.

What the heck could have happened and what part is failing me?

Anyone ever had this happen to them?

This is so weird.

[alexpigment]

I would suspect a switch issue or failing solder joint before a problem with the pickup itself. Since it affects the bridge pickup alone, you could go really scientific and just wire that pickup to the input of the volume pot (grounding to the body of the same pot) as a test. If it works fine there, then work your way back.

On the other hand, you could just reflow solder at the pickup selector switch and see if that fixes it. One last thing to note is that Jazzmasters are notorious in my book for parts accidentally touching something grounded within the body. As such, it’s always ideal to test with the pickups in but with the pickguard off if you have the wire length to do so. It’s not uncommon for everything to work properly until you screw the pickguard down. That’s when I get out some electrical tape and put it in potential contact areas in the cavity.

[MKR]

I’m bumping my thread because I found a clue to my problem. The pickup is the culprit, but it’s not dead entirely. At least I don’t think it is. Today I noticed that when I pressed down hard on the pickup, the full sound would kick in.


This makes me think the problem is where the lead wire is connected to the pickup.

What should I do? Take the pickup off and resolder or add solder to that joint?

Any advise would be appreciated.

[alexpigment]

It *could* be the solder joint being bad, in which case you could reflow that solder. Or it could also be that the pickup is touching ground in some way that's partially shorting it out. I usually use electrical tape in the latter scenario, as that's a common problem with toggle switches and output jacks in the cavities when there is ample shielding.

[andy_tchp]

Yes, it (still) sounds like a partial short to shielding.

Be very very F. careful reflowing anything on/around the eyelet of the pickup itself if it's deemed necessary. It probably isn't.

[MKR]

Ok thanks everyone!

[LeftyJ]

My Am Pro II Jazzmaster had something similar a few weeks ago, but the signal would be somewhat intermittently dropping and coming back up. In my case the cause was where I least expected it to be: the bracket with the rollers for the rhythm circuit wasn't properly touching the shielding on the back of the pickguard. After tightening the screws securing it to the pickguard, all was back to normal. But probably not helpful, as you've already found you can get the pickup to sound normal when pushing it.

[MKR]

Problem solved! but it took a while to get there.

One thing i noticed was the ground wire coming out of the pickup was barely holding on. Like a strand or two of wire. eventually it snapped off so i re-soldered the ground wire to the back of the pickup. That didn't fix the problem and the same symptoms persisted. If i pressed on the pickup a certain way, full sound would come back. It was frustrating me, so i decided to take it to a long and mcquade close to my house. Supposedly the guitar tech there was good. He had it for a week and then told me that the pickup was indeed the culprit and needed replacing. He said he measured the resistance. Too bad, i thought. I thanked him and said that i would do the work and buy the part myself.

Then when i get home i notice the pickup sounded perfect! i could tell it was finnicky and if i pressed on it, the sound would cut out and return. Eventually it just sounded thin and crappy again. So this time i took the pickup out. Cleaned up the solder job abnd re attached that ground wire. Tested the resistance myself and BOOM a normal reading! I resoldered it back into the guitar and everything works and feels solid now!

So yeah thanks to everyone here to chipped in with some advise. Because of this thread, all signs pointed to this being a ground / wiring issue. And it was!
I am very annoyed at that L & M guitar tech though. Note to anyone in toronto, if you're thinking of bringing your guitar into the Danforth location in Toronto, think twice. The guy must have done the bare minimum check. I wonder if he even took the pickguard off. probably just checked the resistance via a patch cord plugged into the jack.

Ultimately i'm very pleased because i didn't want to replace the pickup in the first place. And i feel satisfied having done all the work myself.

[MKR]

should i say anything to that guitar tech? I kind of feel like i should....