The emergency flashers are used to warn other drivers when the vehicle has to be stopped in the road due to a breakdown, etc.
Press the switch.
All the turn signal lights will flash.
To turn them off, press the switch once again.

Emergency flashers
If the emergency flashers are used for a long time while the engine is not operating, the battery may discharge.
If your vehicle has to be
stopped in an
emergencyBefore refueling the vehicle
Close all the doors and windows, and turn the engine switch to the
"lock" position (vehicles without a smart key system) or off (vehicles
with a smart key system).
Confirm the type of fuel.
Fuel types
Unleaded gasoline (octane rating 87 [research octane number 91] or
higher)
...