Red Bull Racing boss Christian Horner has made it clear that engine supplier Renault had to solve the problem of the faulty alternators before the next Grand Prix in Singapore.

The alternator on Sebastian Vettel's car failed with just a handful of laps to run in Sunday's Grand Prix of Italy in Monza.

A lonely Sebastian Vettel walks back to his garage in Monza... (Photo: WRI2)

“A hugely disappointing race -- our first non-points scoring race since Korea 2010,” said Horner in a team press release.

“It was a repeat failure on Sebastian’s car with the alternator and we need to look into it and work with Renault to ensure it doesn’t happen again. It’s already cost us a victory in Valencia and now a points-finish again here in Monza,” he said.

“We changed the alternator on Sebastian’s car yesterday during FP3, but unfortunately we had the same failure in today’s race,” said Cyril Dumonyt of Renault.

Remi Taffin, Renault Sport F1 head of track operations said in both cased, the alternator failed.

“We introduced a new spec’ of alternator following the problems in Valencia and believed this would overcome the issues,” Taffin explained.

“We are still looking into why the part failed again here but we do know that even though the alternator was being operated entirely within the prescribed range, the part itself overheated and shut off the power supply. This is a priority between ourselves and our suppliers and we have to ensure we are fully on top of the problem before Singapore,” the engineer added.

Remi Taffin also explained that the failure is caused when the alternator's internal temperature gets too hot for it to be able to produce the electrical energy that the car requires.