Honda ADV350A Owner's Manual page 71

The emergency stop signal is not a system
u
that can prevent a possible rear-end
collision caused by your hard braking. It is
always recommended to avoid hard braking
unless it is absolutely necessary.
The emergency stop signal does not activate
u
with the hazard switch pressed in.
If the ABS stops working for a certain period
u
during braking, the emergency stop signal
may not activate at all.
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