A complete failure is pretty rare, and usually fairly easy to diagnose. Unless the pickup suffered a sudden stress that affected both elements - like having the jack yanked off the bass, pulling the pickup elements off the bridge with some force (and damaging the delicate wires to them in the process), I'd think it would be rare for both transducers to "fail" at the same time.
If you had a working pickup, and now you've got bupkus, I'd bet on a break in the pickup's cable, or a short or failed solder joint in the jack.
In fact, first thing I'd check is your 1/4" cable. Try a different cable, see if you get better results.
If you rule out your signal cable, open up the output jack for the pickup and see if you can find a failure there - broken solder joint, a short of the ground wire to the signal wire, etc. The jack itself could be broken, too - but it's probably sealed to the point where you won't be able to confirm that.