I found the following on a blog - has anyone else had this experience with the Bionx system?
Interesting and thank you all for posting this. I have had a similar experience viz my bionX kit NiMH did not activate the motor at all when the battery was cold: there was no regeneration or assistance actuation, and no speed readings, although the controller read about 90% batt charge and all other controller functions appeared normal (no speed/distance readings either though). The diff from above postings is that my motor showed no activation at all i.e. there was no on-off intermittency. Charging at room temp for 30 mins solved this (presumably ambient temp plus heating cells via charging warmed the batt), but I have to say the battery was not particularly cold (i.e. not "frozen" when this happened - I would guess around 2-5degreesC. I wonder what the freezing temp of the NiMH cells is anyway. Subsequently during the immediate ride after this charging the batt charge level indicator on the controller vanished for about 10mins for some reason, and then reappeared. Strange, inconvenient, but not critical.
The symptoms match mine exactly and my bike has been sitting outside in subzero weather - it is now in the warm and I will try it in an hour or so. A bit of a pain, though, if it has a problem with cold weather.