Les Paul wiring HELP

Gusmc01

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Took the PCB and '61 humbuckers out of my 2014 LP and installed a 500T/496R set. Got it all wired up and plugged it in and the pickups have basically no output and I get major buzz when I touch the selector switch and other parts of the guitar (grounding issue). Where did I go wrong on the wiring?
21483.jpeg
 

ARandall

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I'd be reflowing the joints on the back of the pots for starters....if you've got less than a 40W iron then replace it before you do this as you'll cook the pots. But also you need a lot of heat applied for a short time to make these joints in the first place. The solder should not look like a mound or hump, but a puddle.
 

Stinky Kitty

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Dial all your pots to 0 before soldering so that if you are in there too long and too hot, you won't damage the race in a critical area.

Ensure the ground wire to the string stop is properly in place.
 

Gusmc01

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Thanks for your reply.....and where exactly does the other end of that ground wire attach to the string stop?
 

Spurg

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The ground wire should go into the body and it gets pinched between the wood and the stop tail piece bushings. I doubt that's your problem unless you pulled it out too far.

It sounds to me like you have the wires touching somewhere they shouldn't be and grounding out. I had this same problem once when installing a new input jack. I'm assuming you didn't install a new jack, but you could have two wires elsewhere that are touching that shouldn't be.

Did you have a schematic that you worked off of for this wiring configuration? Can you upload that if you do?

I'd recommend undoing the wires and starting one at a time and see if you can get sound with just one connected. There's a lot going on in this photo and it doesn't look right to me. The large grey wire you're holding back with your finger, where is that going? Where is the pickup selector wire? You have a lot of wires going to your pots that I can't see where they're coming from.

It is possible you did fry one of the pots, but I'm pretty sure you would be able to get some sound out of it unless you fried both pots. Did you linger for a while on either pot with the soldering iron? You can check the pots resistance (OHMs) with a multimeter if you have one.
 

Gusmc01

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Thanks much for the replies. I wasn't working from a schematic but from another LP I have that has traditional wiring from the factory. I was just checking a schematic and it had the white and black wires taped together, not white and green, so I will try that. The wire I am holding with my finger is the bridge pickup. Both pickups and the selector switch all have the exact same color wires so it is hard to keep everything straight. I used the blue tape to label the pickup wires.

I'm afraid I may have cooked the pots. I had a helluva time trying to get anything to stick to the back of those pots. I have a 75W adjustable temp iron so I'm confident I had it hot enough. I finally sanded the back of the pots just to rough them up enough to get the solder to stick. It was really frustrating. I've never had that problem working on my Fender's. Plus the angle working down in that cavity makes everything awkward. I'll post another pic from a different angle....maybe something else will jump out at someone.

21486.jpeg
 
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Cjsinla

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It’s critical to know if it’s white to black or white to green. Also, all that electrical tape is concerning, especially on the wires to the jack.
 

EpiLP1985

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Thanks much for the replies. I wasn't working from a schematic but from another LP I have that has traditional wiring from the factory. I was just checking a schematic and it had the white and black wires taped together, not white and green, so I will try that. The wire I am holding with my finger is the bridge pickup. Both pickups and the selector switch all have the exact same color wires so it is hard to keep everything straight. I used the blue tape to label the pickup wires.

I'm afraid I may have cooked the pots. I had a helluva time trying to get anything to stick to the back of those pots. I have a 75W adjustable temp iron so I'm confident I had it hot enough. I finally sanded the back of the pots just to rough them up enough to get the solder to stick. It was really frustrating. I've never had that problem working on my Fender's. Plus the angle working down in that cavity makes everything awkward. I'll post another pic from a different angle....maybe something else will jump out at someone.

View attachment 537413
I almost always do work outside the cavity. Put the components in the jig, solder ground tabs to case, solder caps to pots, prep pot surfaces and make switch and pickup connections all outside. The only connection I make with the harness mounted in the cavity is the bridge ground wire.

Try double checking your wiring diagram and reflowing all joints to start.
 

Gusmc01

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I almost always do work outside the cavity. Put the components in the jig, solder ground tabs to case, solder caps to pots, prep pot surfaces and make switch and pickup connections all outside. The only connection I make with the harness mounted in the cavity is the bridge ground wire.

Try double checking your wiring diagram and reflowing all joints to start.
Great suggestion, I will definitely do as much as I can OUTSIDE the cavity next time.

Thanks also to the member who recommended turning the pots to zero when soldering. I believe I did when I was doing the work, but I had never heard that before.
 

DarrellV

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Thanks much for the replies. I wasn't working from a schematic but from another LP I have that has traditional wiring from the factory. I was just checking a schematic and it had the white and black wires taped together, not white and green, so I will try that. The wire I am holding with my finger is the bridge pickup. Both pickups and the selector switch all have the exact same color wires so it is hard to keep everything straight. I used the blue tape to label the pickup wires.

I'm afraid I may have cooked the pots. I had a helluva time trying to get anything to stick to the back of those pots. I have a 75W adjustable temp iron so I'm confident I had it hot enough. I finally sanded the back of the pots just to rough them up enough to get the solder to stick. It was really frustrating. I've never had that problem working on my Fender's. Plus the angle working down in that cavity makes everything awkward. I'll post another pic from a different angle....maybe something else will jump out at someone.

View attachment 537413
You still have that vintage metal plate under the pots with that handy terminal strip in the middle.

One lug is riveted and soldered right to the metal base plate.

You could solder all your grounds there and avoid soldering on the back of the pots all together..

Just my 2 cents as a Norlin owner.. :eek2:
lp wiring.jpeg
 


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