Jenson Button set the quickest time of the second day of testing at Jerez as Red Bull hit yet more reliability issues.

The new McLaren finally appeared for the first time on Wednesday morning and Button completed 43 laps with a best time of 1:24.165. That tally alone was almost half the amount of laps completed in total by all the teams on Tuesday, with the second day seeing much more running.

However, for Red Bull there has been precious little track time as Sebastian Vettel completed just eight laps before a reported energy store issue curtailed his day. That meant the 2013 drivers' champion has driven just 11 laps in the RB10 across his two days in the car before handing over to Daniel Ricciardo tomorrow.

Kimi Raikkonen was second quickest for Ferrari, less than a second slower than Button and just ahead of Valtteri Bottas in the Williams and the impressive Mercedes. Nico Rosberg completed 97 laps - more than the entire field managed on the first day - despite not emerging from the garage until two and a half hours in to the day as Mercedes waited for new parts to arrive following Lewis Hamilton's front wing failure on Tuesday.

Sergio Perez had just begun his 38th lap for Force India when he came to a halt at Turn 1 with smoke emerging from the back of his car. It took a lot of time for the VJM07 to be recovered as the engine cover needed to be removed in order to stop the smoke.

Esteban Gutierrez was the cause of the first red flag of the day as he ran off track at Turn 5 and had to have his Sauber recovered from the gravel. However, he still managed a total of 51 laps, although his best lap time was nine seconds slower than Button.

Marcus Ericsson also gave Caterham its first timed laps but stopped in the afternoon after 11 laps.

With Toro Rosso failing to run all day, Renault-powered cars have completed a total of 38 laps across the opening two days of running, while Mercedes managed 212 on the second day alone and Ferrari 100.