Toto Wolff has described the repeat of Lewis Hamilton's MGU-H problem at the Russian Grand Prix as "a freak failure".
Hamilton was hit by ERS trouble in China, with Mercedes pinpointing the problem to the MGU-H as the triple world champion started from the back of the grid. At the end of Q2 in Russia, Hamilton suffered the same problem and Wolff says it comes as even more of a surprise after the first one was rectified.
"I would say that what happened today is a bit of a freak failure because it is a scientific assessment process and we had a failure in Shanghai that we understood," Wolff said. "We decided to change the parts and here we go again, the same thing happens so we need to find out if we have identified the root cause of the problem.
"The car is rock solid, it is a fast car, this weekend probably the fastest so far as we have had these two unfortunate problems on the MGU-H."
Wolff wants Mercedes to look at the way it is running Hamilton's car in case settings are to blame for the problem, but ruled out the driver as having any influence.
"I think we have eight power units out there and seven didn’t have any problems and one had a problem twice.
"You need to turn every stone and looking at settings, because it happens in the same circumstances in qualifying twice or in the race, so I wouldn’t exclude anything but it is not something that is obvious because we would have found out.
"It isn’t the driver’s fault, that is definite."
REPORT: Rosberg takes pole as ERS problem hits Hamilton
AS IT HAPPENED: Russian Grand Prix - Qualifying
Romain Grosjean column: Haas brought back down to earth
Keep up to date with all the F1 news via Facebook and Twitter
Today, we at F1i.com raise a celebratory glass to our esteemed founder, Bertrand Gachot, who…
McLaren roared back to the pinnacle of Formula 1 in 2024, clinching their first Constructors'…
Liam Lawson has revealed that he became the target of online abuse by fans of…
As Carlos Sainz prepares for a new chapter in his Formula 1 career with Williams,…
Sebastian Montoya, the 19-year-old son of former Formula 1 star Juan Pablo Montoya, is set…
When former Ferrari team principal Mattia Binotto took on the role of Chief Operating Officer…