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:
Fluids and lubricants
PRODUCTS WHICH MAY BE USED AND THEIR CHARACTERISTICS
(*) For very low temperatures, we recommend SELENIA MULTIPOWER.
(**) For very low temperatures, we recommend SELENIA WR. ...
If an interior light burns out
Modifications or repairs to the electrical system carried out incorrectly
and without bearing the features of the system in mind can cause malfunctions with
the risk of fire.
See “If a bulb burn ...
Lowering The Power Top
Press the top open button approximately one second for the partially open position.
Press the top open button for approximately one second a second time to fully open
the convertible top. ...