Both Ferrari and Haas will spend the remainder of the 2019 walking a tightrope after new Control Electronics were fitted to their cars, in response to the issue which denied Charles Leclerc a maiden grand prix victory in Bahrain a fortnight ago.
Leclerc suffered a power outage 15 laps from the end of a race which he had dominated, an issue Ferrari eventually discovered was caused by a short circuit in an injection system control unit.
According to Ferrari, the issue "had never been seen before on the component in question".
It has prompted the Scuderia to swap the electronics on its works cars and those of customer team Haas, although Alfa Romeo will not take new parts in China this weekend.