Monday 15th August

 The bike wouldn't switch on this morning. I dragged it back inside and unplugged the battery. It was showing a full charge. I put my multimeter and there is continuity across the negative terminal to the controller but nothing on the positive. I ran out of time and had to take the car to work. 

This evening I checked the battery and although it's showing a full charge,  it wasn't giving any discharge. I wasn't sure if there was a signal from the battery management to the controller but after dismantling everything, I think its the battery. So that's an expensive problem. 

I've commuted solidly for 750mikes over the last 6 weeks so I shouldn't feel too guilty about taking the car to work  but I did miss my cycle today. 

I'll phone around the shimano dealers and see what the situation is with battery testing/repairs. I suspect I'll be buying a new one.