Thanks Buzz456. I tried that but it didn't make any difference. The spacebar works for the original CN GP9 but not for the latest repaints.
I did notice that the horn-pull in the cab works okay for the repaints (i.e. sounds the horn) but I can see two horn-pulls, one that moves and one that doesn't.


Even a blind pig finds an acorn in the woods every now and then. 
Thanks Buzz for your help 