Thanks Rog,

You could be on to something mate thinking

I'll double check my depth of hazard switch latching and compare this with the other working switches, I also need to check that my cable tie ribbon anchor point I've looped around the removable PCB cover is not interfering with the microcontroller and or pin 14 in some way?

From above:

[Linked Image]

And from below:

[Linked Image]

Perhaps my cable tie is just physically stopping the hazard switch from pulling down correctly?

Ah the joy, it does seem I need to drop the dash again to at least study these possible causes for my loss of hazards, hopefully it's something simple and easy to fix?