Turning the ignition key to MAR the warning light on the dial turns on, but it should go off after few seconds.
If the warning light stays on (on certain versions together with the message on the display), you will not have steering assistance and the effort on the steering wheel will be increased, steering is however possible. Contact Fiat Dealership.
See also:
Knee Impact Bolster
The Knee Impact Bolster helps protect the knees of the passenger side front passenger
by positioning the passenger for the best interaction with the Advanced Front Air
Bags.
Along with seat belts ...
Passenger Seat Storage — If Equipped
Some models may be equipped with storage under the front passenger seat. Pull
outward on the latch to open the storage compartment.
Passenger Seat
Storage ...
(A) Whenever You Stop To Use TIREFIT
1. Pull over to a safe location and turn on the vehicle’s Hazard Warning flashers.
2. Verify that the valve stem (on the wheel with the deflated tire) is in a position
that is near to the ground.
...