Incompetent garage

[polinsteve]

I have the ignition light on while driving, the alternator charging as normal. I've taken it to a local garage to diagnose. Firstly, they've shut the bonnet with various bits and electrics detached and jammed it shut. They've also asked me if I can get an image of the blue wire on the charging system as they are not sure if the pattern is correct. Apparently, there is a k-bus code but he can't remember what. I can't just collect the car because of disconnected ecu.
Can anyone please guide me as to the bonnet opening method for a possible broken cable, and an image of the blue wire wave pattern?
Thanks