Mercedes has made resolving the MGU-H problems faced by Lewis Hamilton its "highest priority" ahead of the Spanish Grand Prix.
Hamilton was hit by an MGU-H issue which forced him to start from the back of the grid in China, recovering to seventh place in the race. In Russia, Hamilton suffered a repeat failure at the end of Q2 and was forced to start from tenth before finishing second behind team-mate Nico Rosberg.
With Mercedes having believed it had solved the problem after China, executive director (technical) Paddy Lowe says the focus between races has been to ensure there is not a recurrence of the fault.
"Of course, we've all been to this circuit already in 2016 during winter testing - but it's a very different track in May compared to how it was back in March," Lowe said. "It will be much warmer and the tyres will behave differently.
"We have the Hard, Medium and Soft compounds to choose from, which presents some challenges. The Soft will be essential for qualifying but not be a great race tyre, so determining the optimum strategy will be a focal point.
"Qualifying and race starts will also be important, as it is notoriously difficult to overtake at this circuit. But the highest priority is to come back with our MGU-H problem solved, having had a repeat fault over the past two race weekends. The team has been working day and night to understand it and we're targeting a clean weekend all round."
On top of the reliability focus, Lowe highlights the importance of this weekend's race in understanding which teams will be competitive for the remainder of the season.
"Barcelona itself is a circuit which is very demanding of all aspects of car performance. There's a common saying in Formula One that if you're quick around Barcelona, you'll be quick everywhere. This makes it an important landmark in the season to see where you stand in performance terms, as most teams will be bringing a range of upgrades."
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