#1
A few months ago I bought a used Vintage Les Paul copy (not sure if it's a V99 or V100 - is there an easy way to identify it?) as I get sick of changing tunings all the time.

The bridge pickup works fine, but when I switch to the neck pickup there is a huge drop in the sound level.

Any ideas what this could be?
Gibson SG
Ibanez K-7
Vintage (V99 or V100 not sure which!)
Crafter FX-550EQ

Korg Pitchblack
Boss DS-1
Digitech Bad Monkey
Blackstar HT-5 Combo
Line 6 HD500
#3
I forgot to add that the tone and volume controls both seem to function fine, the overall volume level just drops by loads
Gibson SG
Ibanez K-7
Vintage (V99 or V100 not sure which!)
Crafter FX-550EQ

Korg Pitchblack
Boss DS-1
Digitech Bad Monkey
Blackstar HT-5 Combo
Line 6 HD500
#4
pop the cover off and check the wiring something might have been bumped out of place. Otherwise it could just be the pickup dying I'd take it to a tech to verify. In which case you need to replace the neck pickup.
#5
Quote by Obsolete80
A few months ago I bought a used Vintage Les Paul copy (not sure if it's a V99 or V100 - is there an easy way to identify it?) as I get sick of changing tunings all the time.

The bridge pickup works fine, but when I switch to the neck pickup there is a huge drop in the sound level.

Any ideas what this could be?

The best answer on what to do with a used guitar in your situation has been given - guitar tech lol.

There is an easy way to tell the difference between the V99 and V100.

The V99 has a bolt-on neck and the V100 has a set neck
#6
There are a lot of reasons 1 pickup can be quieter than the other. It could be a demagnatized magnet, bad pot, a short, or it could be as simple as the pickup is just sitting too low. 1st thing I'd do is check the DC resistance. You can do that without even taking out the pickup by simply turning the volume and tone full on, plugging a lead into the guitar, and then touch one multimeter probe to the tip of the other end of the leand and touch the other probe to the sleave. I'm not sure what the resistance of your pickups should be but because it's a vintage lp copy I'd guess that you want it to read at around 8K. If it reads at 3.5K to 4K then you know that half the coil is shorted out.