Mar.23 (GMM) F1's governing body has cleared Red Bull and Renault following accusations they are deploying an 'illegal engine trick'.
Reports suggested Mercedes, having analysed sound recordings of the Red Bull RB8 in Melbourne, suspected the 'trick' of cutting more than the allowed four cylinders in corners was not legal.
"As far as we are concerned, it's legal," said the FIA's Charlie Whiting in Malaysia.
There was some good news for Mercedes at Sepang, however, as its W03 passed pre-race scrutineering despite Red Bull and Lotus continuing to argue that its 'W-duct' system is not legal.
"The car got the green light again," competition boss Norbert Haug told Kleine Zeitung newspaper.
Some suspect that the innovation could give Mercedes such a top-speed advantage on Sepang's long straights this weekend that pole position is already in the bag.
"I think some get a little bit too excited," smiled Michael Schumacher.