Joined: Dec 2011
Posts: 2,519
Likes: 18
From: Fort Worth, Texas
Bikes: 2000 Bianchi Veloce, '88 Schwinn Prologue, '90 Bianchi Volpe,'94 Yokota Grizzly Peak, Yokota Enterprise, '16 Diamondback Haanjo, '91 Bianchi Boardwalk, Ellsworth cruiser
That sensor has no battery. It runs off the battery in the computer. It sounds like the guy you spoke to was assuming you had a wireless model, and those do have batteries in the sensor head.
If the wheel rotation is not registering, you need to get the sensor closer to the magnet and play around with the height of the magnet and sensor relative to each other. Most sensors have a sweet spot.
There is also a possibility you have the wrong mount, but that it is close enough that the computer fits in it, but doesn't make contact.