Disconnect the brake sensor. The brake sensor is a small wire running below the lever which controls the rear brake. It is held in a neoprene sleeve glued to the brake lever and can be slid back and forth within this sleeve in order to give you some adjustment. On G1 Consoles this wire connects directly to the console. On a G2 console its the small wire running from the throttle unit to the brake lever. Just unplug this small wire and you've disconnected it. Note: This disables the regenerative braking mode.
Ride the bike and see if it assists you. If it does, reconnect the brake sensor and adjust it according to the instructions to adjust the BionX brake sensor.
Take a look at the rear axle on the left side. There is a little notch or gap in the end of the axle. This gap orients the motor and tells it when to assist. Is the gap pointing straight down? If not, you'll have to reposition it for proper function. To do so, you'll have to first loosen the "torque collar" holding the axle in place using aBionX puller tool, and then reposition the gap straight down to 6 o' clock before tightening the axle nut again.
It's important to tighten the axle nut enough after setting the torque collar to the proper position. If you don't tighten it enough the torque collar could slide when riding and reposition itself. If you tighten it too much you could snap the axle (pretty unlikely). When tightening the axle nut you must make sure it is tightened to a torque of 30ft/lbs. That means if your wrench is 1 ft long then you need to push down with 30lbs of force to get the nut to the correct torque. If you have a longer wrench, grip it 1 foot from the axle and press there. If you have a shorter wrench, slide a pipe over it to extend the length.
If you don't have a torque wrench (most people don't) you could bring the bike to a shop to have that torque specification checked or, you could just do your best to get the nut on there good and snug - without straining so hard that it seems unreasonable.
Follow Instructions for Diagnostic Mode to see if your motor's "Strain Gauge" is working.
Strain gauge doesn't work...
If your strain gauge is not working you'll have to contact your dealer for further assistance. If NYCeWheels is your dealer please submit a BionX System Analysis Form.
Strain gauge does work...
If your strain gauge does work there must be a communication problem somewhere within the wiring harness. Check all connections and pay specific attention to the round plugs and thinner wires. These are communication wires.
If you can't find any connection issues you'll need to swap out a different wiring harness or try the motor from the non working bike with another BionX (if you have more than one). For support, contact your dealer or submit a BionX System Analysis Form to do so.