He is unhappy at their inability to finish higher up the field in 2012, despite having a more competitive car than in the two previous seasons.
“We need to work hard to improve our level of consistency and ability to challenge at the front.”
Last time out Mercedes finished seventh with Michael Schumacher and 15th with Nico Rosberg in the British Grand Prix, helping confirm former Ferrari team principal Brawn’s concerns about consistency – Schumacher had finished on the podium in third two weeks’ previously in Valencia.
This season Brackley-based McLaren have, at times, been able to keep pace with front runners Ferrari, McLaren and Red Bull, and they were dominant in China as Nico Rosberg secured his first career victory.
But their F1 W03 car appears to be more sensitive than its competitors to the differences found among the circuits in the Formula 1 calendar.
“The Hockenheim layout [the venue for the German Grand Prix on 22 July] should be more suited to the F1 W03 than the high-speed Silverstone layout,” Brawn added.
“We are bringing some further improvements to the car which should help our performance.”
Mercedes, whose factory is based near Hockenheim, will want to put on a good show for the German public, especially the talismanic Schumacher, who has born the brunt of the team’s reliability problems this season.