Out of all Fiat cars, is it only the 500X which has an EPB electric parking brake (you press/release a small lever on the dash and a motor pushes out the pistons in the rear calipers, or pulls them back in).
My Jag XF and my wife's Volvo V60 has them, the one on the V60 is easy to check and maintain (no complicated interfacing with an ECU to tell it to back off the pistons, or telling it that new pads are fitted) although the switch is badly located and works in revers, ie: push to apply, pull up to release
I wonder how easy it might be to retro-fit to a Coupe to avoid all those frozen handbrake issues? (but create loads more with "electrically" frozen handbrakes?)
The 500X (same rear brakes as Jeep Renegade) looks to have a larger 278mm rear disc, but the design principle is similar with a carrier that bolts to the hub, and two bolts to secure the caliper to the carrier. If I could pick up one or a pair of EPB calipers for next to nothing I might have a play...