On 12/03/2019 19:15, Bill Wright wrote:
If you can find the actual sounder you could simply snip one of the
wires (or fit a switch), then tape up the end so it doesn't short on
anything. The sounder is likely to be a little round thing somewhere
under a panel at the back. Get someone to find it by listening.

I've looked through the user manual and can't find anything. The
maintenance manual I can't find on line.

Yes I checked the manual as well, nothing much on electrics.
Trouble could be the bleeper also doubles as the horn.