Renault unsure of alternator failure cause
Renault has confirmed that an overheating alternator caused Sebastian Vettel and Romain Grosjean's retirements from the European Grand Prix but it doesn't know what caused the problem.
Vettel had a clear lead before a safety car period in Valencia, but on the first lap back up at racing speed he was forced to retire. Grosjean also had to park his Lotus a few laps later when chasing Fernando Alonso for the lead and it has been confirmed that both failures were a result of overheating alternators.
The problem facing Renault now, however, is determining what caused the alternators to overheat, and Rob White - deputy managing director of Renault Sport F1 - admitted that more tests needed to take place.
"We've checked over the parts thoroughly now and it seems that there were no obvious reasons for the failure," White said. "So we are conducting further tests on the dyno at Viry to replicate conditions and double checking the findings."
White also said that the safety car period did not cause the issue, and actually delayed Vettel's problem from causing his retirement earlier.
"We had evidence that the alternator on Sebastian's car was showing signs of overheating before the safety car period, but the slower speeds prolonged its life expectancy slightly. Of course, when Sebastian went back up to racing speed the problem stepped up again and the result is now well known. With Romain's car, the problem occurred very suddenly some laps after the safety car had been withdrawn."
White added that Renault would look at various measures to prevent a similar problem occurring at Silverstone, with using a different batch of alternators the most likely solution.