My Mrs has a 2016 Corsa energy with 20k miles on the clock. Yesterday, out of the blue, after a short journey, it wouldn't start. After turning the key, there was no click, no turning over, nothing. She tried again, and it started immediately!
If you are worried it may let you down again you are going to have to get it or get it scanned for fault codes in the meantime follow the instructi9ons below and when you get to the point where it shows him rev the car the next press will show you if the alternator is working properly.