Nope. YOU tell us what you did (so far) to fix it.
All threads contain good advice. It's up to you to apply it (and not cherry picking: you replace alternator but leave old battery, because you think "it's good").
Solution is more than one thing to fix/swap. Most common scenario. Most likely power delivery/quality. And car overreacting while "diagnosing" it (ECU and/or Body computer - therefore there is a software update, officially, "Fiat aftersales" website).
Steering unit is an option too (electronics, sensor ect.). You forgot to add that (it deserves separate category, not "something else").
And "BCU replacement" should be called "replacement/reprogramming".
