ok so i haven't been on here in years but i figured this is as good a place as any to seek out some help.

i have a 2002ish gibson sg special. stock electronics, with the exception of the bridge pickup that was replaced at around two years old. so its set up like most other gibsons - 498t bridge, 490r neck, 2 volume, 2 tone, 3 way toggle, output jack.

I've noticed lately that the guitar doesn't seem like it has the same output it used to. when switching guitars, this one seems way more subdued than i remember it used to be. at first i thought it might have been the bridge pickup like what happened the first time years ago, but when i tap on both pickups with my pick, it sounds equal in both positions. and the neck doesn't sound louder than the bridge either.

my assumption is i have something bringing down the output of both pickups before it makes it way to the output jack. quick background on me: I'm an auto mechanic who's pretty good with wiring and diagrams but has never worked on guitar wiring before so I'm not sure where to start checking and what kind of specs I'm looking for.

can someone lead me in the right direction here? any help would be appreciated.

thanks in advance.
first things first I'd tap the pickups top with a screw driver to see what pickups are selected , this is a trick i learned from the founder of EMG and I do this a lot.

besides that look for loose wires or cold solder joints, if you want to post some photos i'm sure there is a few people on here including myself who can help you out.
So I took the back cover off and peeked around. Even took a little 9v pocket amp and plugged it in while I was wiggling around all the connections at the pots and jack and toggle switch. No change. I have a picture of it if anyone wants to see. But i'm not quite sure how to upload it here.
sure someone on here can help you out, pickup height is very important too for getting higher output.
get some contact cleaner and clean the switch and the jack. I have a feeling the 3 way is gunked up, what your describing has happened to me more than once and it was the switch.
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