But to determine that the bass is a player without plugging it in? I don't think so.
I can definitely tell if a bass is a player without plugging it in. I can't tell how the electronics sound, but I can tell if it's otherwise well-built, solid, resonant, and the potential for bonding and player interaction with the instrument. Absolutely.
In fact, that's my top priority with a bass, not the electronics. Electronics can easily be switched and modified to my taste and needs, but the construction (fit, finish, etc.) is more difficult to alter and improve.
A bass like OP's would be a dilemma. If it's a tweak or quick fix, I'd gladly spend the time and effort on a great-playing bass. If it's going to cost me money for replacement parts, I'd have to check on warranty coverage and decide. For sure, if I had a great player in my hands, it would be hard to return, because the next one could very well not be as good a player. That has happened to me a few times, and it's more disappointing and frustrating than a relatively small repair.
Assuming it's a great-playing bass, I'd be opening cavities (which will not void warranty or return option) and taking a peak, and if I couldn't figure it out, I'd have my tech do a free diagnosis for me. Then I'd decide how to proceed from there. Manufacturers and retailers are sometimes happy to reimburse for a little tech work after the purchase, you just have to research it first to see what they might be willing to do for you.