is this a switching problem


Senior Member
hey guys, got a bit of a problem that i can't seem to rectify:

i recently installed a new set of humbuckers into my epi sg, with the help of my dad (who can actually solder without burning his hands off). i have since run over and over the wiring diagram, as i am having sound issues. about 30% of the time, whenever i switch from the rhythm to the trble pickup, the output of the pickup drops dramatically. as in, it drops to about 30-40% power. flicking back to the neck, and its fine, but the bridge pickup just drops straight out. then i might flick back and forth a couple of times and it will be back to normal. it's really weird.

i have checked to make sure all the earths and leads are connected right etc etc, and all i can really pin it on at the moment is possibly a faulty switch? i've also noticed that sometimes my esp explorer seems to do it, not as frequently though (maybe 2% of the time). and really, its a pain in the ass, reliability for gigging goes out the window.

could this be the result of a faulty switch? ??? i've never had it happen before, so i dont have a very good idea, and i'm pretty new to the electronis side of modding guitars. the explorer is about 2 1/2 years old, the sg about 1 1/2.

its driving me insane.  :tard: :tard: ??? :icon_scratch: :-\
If you used the original switch in the Epi; that is most likely not the problem. The guitarist in my girlfriend's son's band had his Dad try to put a set of SD Alnico Pros in his Epi LP and was getting little or no output from those PUs. If your's is a relatively recent Epi SG, the pots and other components Epiphone is currently using are cheap as shit and apparently can't take much heat without flaking.

Get a set of REAL pots; preferably CTS, and new caps and some wire; and trash all the cheap crap that came in the Epi SG, only the PU selector switch and the wiring from it to the control cavity are salvagable. As Epiphone is using the 10 for a $1 cheap assed mini pots, you will need to ream/drill the holes to 3/8" to get real pots to fit. Just use the std. LP/SG wiring diagram with the new components and all should be well.
Two things can happen in an SG.

1.  The switch is right there where the wires have to go, and ya have to be careful that they don't touch the switch.  Shrink tube is what Gibson uses, but I'm not sure on the Epi.  A bit of tape on the braid would be fine.

2.  I've seen more than once - a bad connection from braid to pot body and/or a little whisker of wire punching through from the braid into the core of the wire right there at the pot.  I'm not sure why on SG's but I've got two Gibson's and a Guild here, and its been on both Gibsons with pickup changes.  I've done dozens of other pickup changes no problem, but something on those SG's makes me think they're prone (the wire does bend a bit more).

Leave the cover off.  Pass a bit of clean white paper biz card thru the leaves of the switch when its close (do both sides that is).  Then also try that with a bit of alcohol on the card as well, in case its some splatter on the switch.  And if that doesn't fix it completely, get it to happen and wiggle wires really careful till you find it.
well. thats slightly embarrassing. showed a mate of mine the electronic cavity (and he doesnt play guitar by the way), and he pointed out within about 10 seconds that the switch was almost touching the non-conductive painted sides, creating a short loop. i moved it about 5mm and the problem is solved.

now i just look like a knob
Sometimes the simplest solution is right before our eyes! I'm guilty too!! Glad it was a simple fix!
BB in SC