Nico Rosberg has revealed that it was an electrical problem that caused his W04 to stop during Sunday's Australian GP.
Racing towards a solid points finish, the German pulled off the track at Turn Four on lap 27.
"There were some cuts and then an electrical problem," he told the BBC.
"The car felt okay - everyone was sounding very positive in my ears - but apparently it wasn't so great."
Meanwhile, the 27-year-old also revealed that he had been suffering "terrible" graining to his tyres due to the colder than expected temperatures in Melbourne.