I bought a used 8881 battery box. It doesn't appear to work with anything. When I test it with a multimeter, I only get a voltage reading of ~0.5V.
I tested each of the batteries, they each come out ~1.6V (as I'd expect from a AA battery).
It may be that I'm not using the multimeter as intended, and that both the lights and the motor I'm using to test this are broken, but it seems more likely that there's a problem with the battery box.
Any thoughts on what the problem might be?