If you're still struggling with this.

Get the car in the air, remove the undershield(s) and unbolt the two 10mm's holding the latch in, pull the latch out towards the engine and open the bonnet, you will break the small white X piece when doing this, but they are the cause of the fault anyway, and if you know how to built them back up, it will only cost you about 40p!

Done dozens of these in work now.