Last weekend Charles Leclerc suffered an MGU-H and turbo failure that cost him victory in the Spanish GP, and which Ferrari has already addressed.
However in FP1 at the Monaco GP Mick Schumacher of Haas and Valtteri Bottas of Alfa Romeo both suffered MGU-K failures that cost them track time and required their gearboxes to be replaced for the following session.
Bottas also had a comprehensive power unit failure in practice in Barcelona, and there have been other issues across the three Ferrari-equipped teams.
While not going into specifics Binotto acknowledged that reliability remains an issue, while also pointing out that rivals Red Bull have also experienced costly problems in races this year.
“Reliability is always a concern,” he said when asked about the reliability issues by Autosport. “When something is happening, it's never great. It's worrying us, we're looking at what happened, and sometimes you've got straight explanations.
“And it can be caused by external accidents, it can be caused by exceptional circumstances. But other ones may be of worry and concern.
“So reliability has been a key factor so far in the championship, because we failed in Spain, and I think Red Bull as well, they've got three DNFs. We've got one, our customer teams got some as well.
“So it's a challenge, as with performance reliability, [that] is certainly a big challenge, and reliability when you've got concerns, it's never obvious to fix them in a short time.
“So yes, it is a concern, but it doesn't means that we are too concerned, I hope Christian [Horner] is more than myself!
“But let's do our best job from now to the end of the season. And hopefully everything will be smooth and clear.”
Binotto did not want to elaborate on Leclerc’s Barcelona problem.
“What can I tell you? Not much,” he said. “We did an analysis. We failed and damaged both the turbo and the MGU-H, so they will not be repaired.
“Obviously, we found the root cause. We fixed it here for Monaco and the next races. And that's all the detail I will tell."
Alfa Romeo boss Fred Vasseur said he was confident that Maranello will get on top of the problems.
"This is in Ferrari's hands, and they are taking care of it, and I am not worried that they will improve the situation quickly," he said.
