Giant 2017 Full-e help

[AnthonyDevon]

Hi, after years of faultless commuter riding I put my battery in this morning and the screen flashes on for a second but then switches off. Battery button says battery full and I think I've done the battery diagnostic right and it appears ok.
Can anyone shed light on what this might be? I'm lost without my bike. Can't walk far due to a back injury and this is my lifeline to the outside world.

 

[ElHegpah]

With a removable battery, a common cause of issues are the contacts on the battery, or the mount, or the wiring from the mount to the controller.

Also look for a loose plug or damaged wire, especially if it fell over or had a crash or other impact event.