REUTERS: Mercedes have modified a 'magic button' on Lewis Hamilton's steering wheel to prevent a repeat of the Azerbaijan Grand Prix error that cost the seven times world champion the Formula One championship lead.
Hamilton revealed after the Jun 6 race in Baku that he had accidentally hit the button at the re-start, leaving him without rear brakes into the first corner and sending him off track and from second to 15th.
Red Bull's championship leader Max Verstappen had already crashed out and Hamilton, attempting to pass the Dutch driver's team mate Sergio Perez for the race win, had been set to regain the overall lead.
"We've just put a shroud around it to make sure that I can't accidentally touch it in future," the Briton told reporters at the French Grand Prix.
"That's for the short term. Obviously the wheel's not so easy to change or to move buttons. We'll look for a longer term solution."
Hamilton said after the race in Baku that what happened had been a stroke of bad luck.
"It definitely wasn't any pressure from Max and I don't even count it as a mistake," he said on Thursday. "I don't feel any pressure, I feel pretty relaxed.
"You can't always be perfect. A mistake is when you often drive off the track through missing your braking point or hitting the wall.
"It was kind of an unforced error, really just something that we had that was sitting there that could have happened at any point. It unfortunately bit us pretty hard but you learn from the experience."
Hamilton is four points behind Verstappen after six races, despite having won three of them.
Baku was the champion's second big mistake of the season after sliding off track and nudging the barriers in Imola in April before the race was stopped, throwing him a lifeline. He ended up second.
The most successful Formula One driver of all time has taken just seven points from the last two street races in Monaco and Baku but should be on happier territory at Le Castellet this weekend.
The Briton has won the last two French Grands Prix from pole position.