I just purchased a second-hand Yamaha RBX 374. I only have 3 days (minus a few hours) to return it if I find any problems with it.

I have read online that some guitars of this particular model have battery problems, i.e., the active pickups drain the battery more than they should. Some users have complained that the problem isn't resolved even if you unplug the guitar after playing.

Could anyone please reply ASAP and tell me how I can check if my guitar has this problem or not? I have very limited time to check this problem, so a quick and good answer would be highly appreciated.

Well, simply put, if your battery has drained out in the three days, there surely is a problem.
You could put a brand new battery in and see how low it goes with a battery tester after 2 days or something. It shouldn't budge much, some active electronics use more than others, but certainly none should kill a battery in 2 weeks unless you forget to unplug it. I am not familiar with battery draining while the bass is unplugged, I have had no problems with my active electronics on that department.

Check out this link.
Gear pics

Quote by Cathbard
Bugera cloning Blackstar is a scandal cloaked in a tragedy making love to a nightmare.