I feel the horn RFR needs amending (or clarifying).
It really should be worded as for the Hazard lights…
MOI ‘Operate horn with ignition switched on & ignition switched off’
RFR ‘Horn does not function with ignition switched on’ or ‘Horn does not function with ignition switched off’.
The horn – the vehicle’s audible warning device – needs to function to ‘…warn other road users of your presence…’
