Fitting Wilkinson Humbuckers in my Epiphone LP. Need help please (SORTED)

ICBM

kPATm said:

Silence

You've got a short in the bridge pickup wiring somewhere. If you still get silence when you turn the bridge pickup volume control down to about half, it's between the volume pot and the switch; if the neck pickup comes back on then it's the bridge pickup or its cable. 

It could be at the end of one of the shielded cables - if you get the shield too hot when you're soldering it, it can melt through the insulation. Try pulling the core out a bit at the ends and see if you can find it - often that's all you need to do to fix it, if you can move if far enough that it doesn't touch.

The proper cloth-braided wire is much better for this reason, you can get that as hot as you like without melting it.

Also check for bits of stray solder around the terminals on the volume pot, something could be shorted there. It could just possibly be the pot itself, but that's very rare.

kPATm

Still silence with the volume control at half

I cant see anything with the wires. If I touch the back of the switch with a screw driver I get a buzz from the top and middle posts but nothing from the bottom post (neck pickup)

kPATm

Could I move the bridge pickup wire to the neck pick up tab just to rule out a faulty toggle switch?

Nomad

What position was the switch in when you tried touching the terminals to get (or not) a buzz?

kPATm

I did that and the Neck pick up works with the toggle in the Rhythm position and both pickups work in the center position but its come and go. I think (hope) it may be this bloody cable I have. I will wait till I can use the new one tomorrow hopefully. I really appreciate all the help with this ICBM

Nomad

For what it's worth, the Wilkinson pickups in my Lemon Drop have black as the hot wire. Instead of yellow, it has green, and that's ground. Red & white are the in-between wires and are connected together. Although yours appear to have yellow instead of green, it might be worth putting yellow to ground and black to signal.

kPATm

I will wait until I try my new cable before I do that but TBH I think it is wired correctly.

ICBM

You have to work this out logically! It isn't the cable if one pickup works and the other doesn't. The fault is clearly in the guitar. (The general buzz might not be though.)

If you still get silence in the middle position when the bridge volume is down to halfway, the fault is the cable between the volume pot and the switch, or just possibly the pot itself.

If it's intermittent it's likely to be a very light contact between two things that are shorting. Moving or carefully pulling the cores of the shielded cables might show it up.

Those switches can also be problematic though, and you can't easily get into them to find out or fix them.

With the amount of time and effort this is all causing you, I'd be inclined just to get the decent wiring kit and be done with it - the higher quality components are much easier to work with too.

(Swapping the yellow and black wires won't help either, unless there is a short in the pickup, but that's been eliminated by still getting silence when the volume control is turned down.)

kPATm

I agree about the time and effort. I may have ago at it again today and if I get no joy then I may just get the kit linked to earlier

kPATm

I have tried again and I have noticed that the Neck volume control doesnt really have any effect. It seems to be at 10 all the way down to 1 then it stops at 0

ICBM

Are the two non-grounded terminals touching each other?

Seriously, at this point I'd probably just get the better parts and start again! You've learned a lot about troubleshooting but there seems to be a lot wrong with this one. One problem is that if you resolder and resolder stuff you can end up with heat damage or too much solder on things and then it can be one step forward and two back when you're trying to find all the problems.

The wiring does look basically correct as far as I can see in the pics (allowing for some connections being hidden by wires), but at the end of the day you're fighting against basically average-quality parts and wiring.

kPATm

Not that I can see. I ordered the kit linked to earlier

I'll Be Back

usedtobe

Fair play for trying, and persevering with this. You'll learn something, and gain confidence from it.
Fwiw, whenever I have a pickup or 2 not working, post re-wire, I find wiggling wires, and generally manhandling the innards, goes quite a way towards getting things working. Not always, but sometimes, in case of a short, like..

kPATm

I do like messing with things so I dont mind faffing about. I will keep going with this as I wont be able to install the new kit for at least a week as Im dog sitting the Mother-In Laws dog as my Mrs and her Mum and sister head off to Turkey (all right for some) and Im stuck here working taking care of a mutt :-( I can hardly take care of myself

kPATm

Are there any checks I can do with a multimeter than can pinpoint any problems while the guitar is assembled?

A5D5E5

kPATm said:

Are there any checks I can do with a multimeter than can pinpoint any problems while the guitar is assembled?

Yes - check for continuity between each point that should be connected and make sure nothing is connected to ground that shouldn't be.  

It is a pretty good idea to do this as you go as it is much easier to spot and solve a problem as it occurs rather than once everything is done. 

kPATm

I tried another rewire following this diagram. And nothing. The only thing thats different is the toggle. I know ICBM gave me the correct wiring for my setup but I thought it was worth a shot while I wait for my kit to arrive.

Is there a big difference in the way the toggles are wired up. I mean you cant transfer connection from one toggle to the other and expect it to work?

kPATm

And here is how mine is wired

kPATm

Hang on. It does work but the problems with the Neck pickup are still there. May be a dodgy switch?

ICBM

It's essentially the same although the switches are physically different - just that the casing terminal is on the opposite side in the diagram. Everything does appear to be connected correctly.

You're now using unshielded cable for the long run up to the switch though, which will cause noise - although it should confirm what else is/isn't working.

Is the guitar totally dead? If yes, it it silent or does it buzz/hum at least a bit?

If silent, you may have a short in the jack, they do occasionally do that (although rare). If it buzzes it's probably a bad switch - I would suggest opening it up and fixing it, but it's barely worth trying given that they're crap anyway and you have a replacement on the way.

Try touching the centre terminal of the switch with your finger with the guitar plugged in and both volume controls up full, and see whether you get noise in any of the three switch positions, then repeat with them both on halfway, and report back .

I admire your determination to get to the bottom of this by the way!