the answer to the problem is so simple, i shall explain it in point form
Theres 2 path to take now, to determine the problem
1) Go back to guitar tech or another guitar tech, do a through search and have them explain why was there such problem and how to prevent it or at least cut down to minimum
2) Learn from online, read through pages and pages of info, search via google on how the guitar electronic wiring are done. Understand it. Open up own guitar, check through everything.
for 1) Its easier, since the only thing that need to be done, is travelling. And if lazy to travel, then be prepared to spend some time/lotsa time, trying to learn the electronic behind guitar pickup wiring and stuff
for 2) its the longer way, but will result in leanring how to fish, aka knowing how to work on future geetar wiring, do extra mods etc etc.
and if 1) and 2) doesnt sound logical, then 3) Play acoustic geetar.
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and for why most of the time, asking on forum bout troubleshooting issues on wiring wont work so efficiently(when it aint in a diy forum kinda place)
1) Coz we have no idea, cant see, cant check nor troubleshoot with the gear right infront of us
2) Coz we can only make a guess according to what was written, but might be misleading somehow, thus coming out with solution which might not be accurate.
3) Coz we will come out with many solutions, but which are the one that might be a solution, no one knows. And its definitely much harder if threadstarter who has problem in geetar wiring etc, having absolute no idea of how the thing work inside. Even if we can give the right solution, theres no way to fix the problem on own.
imho
if it doesnt sound logical, shoot