the vehicle hasn’t even started

A frustrating day; all the bits of my electric bike conversion are now connected, but it’s not working.  As soon as I switch on, the control panel shows an error message and shuts down.

I have my laptop open at the trouble shooting page and work through the various options.  No joy.

I contact the person I bought it from and he gets on to the manufacturer.  They’re based in China so it’ll be a while before error is gone and vehicle can work again.