have you tried probing the vehicle side connector? Go figure - the manual that I have doesn't have the wiring for the air suspension, rather just has a wire going off to the module. The input side of the RAS is 12V though, so I'd guess that the sensors are running 12V as well.

I would probe for voltage on the vehicle side though - that'll at least tell you what to hook it to on the bench.

Also, did you check the actual mounting bracket before removing the sensor? I thought I remember reading a post about the sensor moving in the mount and showing an incorrect height.