Controls for old style ZM?

[Dusty Chalk]

I recently got in my cheapo old style (3 humbuckers, non-hollow) ZM (without nuthin', not even a bag), and (I was warned, so it's okay) one of the pickups doesn't work (I was going to swap them anyway). I'm trying to figure out the controls so I can figure out which one. It has 3 humbucking pickups, a 3-way toggle on the Les Paul non-cutout horn, and 4 control knobs. I don't think any of them are a master volume, are they? I'm thinking it might be like the Chris Henderson model, but I'm still not figuring it out. Anyone know?

 

[Mikegarveyblues]

Could it be 3 vol and 1 master tone?

If it's that then each pup will have a wire going to the (middle) lugs of the vol pots and a ground to the back of the pot. From another lug there should be a wire going to one of the contacts on the switch. not sure how they're wired up to the switch though...

 

[Dusty Chalk]

Okay, that might be it, or close to it. With all the knobs turned completely off, turning them on one at a time reveals that one knob controls the volume coming out in one of the three switch positions; one controls the volume coming out in the other two, and the 3rd one does nothing. The lowest knob seems to control the tone, but not through the one, only through the two.

I guess I should take off the back plates, huh?

 

[justmund]

Are you sure one isn't a push-pull to activate the middle pickup?

 

[Dusty Chalk]

Yeah, I've pulled on all the knobs. Popped open the backplates, kind of hard to follow because the wires go back and forth across the guitar to get to the switch, but nothing seems to be out of place. The one knob that doesn't appear to affect any volume has a treble bleed capacitor on it. Not sure why that would matter. Will take pics later. I've already cut all the strings, so going to be impossible to diagnose without restringing.

There's a lot of rust, too.

 

[justmund]

You can just tap on the pickup poles with something metallic, that will tell you which pickup is "hot or not"

 

[Dusty Chalk]

Yeah, was going to turn it over to one of my local techs to deal with, they are smart enough to do that, even if my memory isn't good enough to remember that one can do that.