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:
Interior Fuses
The interior fuse panel is part of the Body Control Module (BCM) and is located
on the driver’s side under the instrument panel.
Fuse Panel
...
Glow plug warming failure
The warning light on the dial flashing (on certain versions together with the
message on the display) when there is a failure in the glow plug warming system.
Contact Fiat Dealership as soon a ...
Fiat Doblo Owner's Manual
h1 {color: red;}
h2 {color: green;}
h3 {color: blue;}
h4 {color: #FF00FF;}
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