Turning the key to MAR the warning light on the dial turns on, but it should go off as soon as the engine is started.
If the 
warning light turns on when
the car is travelling (on certain versions together with the message on the display),
stop the engine immediately and contact a Fiat Dealership.
See also:
Controls
(A): Air temperature knob (mixing hot and cold air)
(B): Air recirculation on/off button
(C): Fan knob
(D): Air distribution knob. ...
Changing the battery
If required, replace the battery with a genuine spare part having the same specifications.
If a battery with different specifications is fitted, the service intervals given
in the “Service schedule ...
Instrument Panel Bezels
CAUTION!
When installing hanging air fresheners in your vehicle, read the installation
instructions carefully.
Some air fresheners will damage the finish of painted or decorated parts if allowed ...