Hogweed

Hi all, thanks for providing the forum. I've just acquired a diesel ZX, and it was going fine until the other day it wouldn’t start. If I take a wire from the battery to the solenoid, it starts, so I assume a problem somewhere between the ignition switch and the solenoid. Are there any common failure points here? Of course, knowing my luck, it’ll be the sodding switch itself... Cheers Roger