Renault has vowed to use the time until next weekend's Mexican GP to prove its 2019 car is legal.
Having prepared a 12-page dossier, Formula 1 team rival Racing Point has lodged an official protest against what it alleges is a "pre-set lap distance-dependent brake bias adjustment system" designed and raced by Renault.
It is believed Racing Point thinks the system regulates the brake balance automatically, depending on where the car is on track. But the rules stipulate that it is the driver who must adjust the brake balance.
The FIA ruled that the protest is admissible, and seized the ECUs and steering wheels used by Daniel Ricciardo and Nico Hulkenberg at Suzuka.
A "detailed analysis" of the components will now take place.
Renault said it "acknowledges the protest", but explained that further meetings with the FIA are now necessary "due to the complexity of the 12-page dossier".
"Renault intends to use this recess to prepare an equally detailed case to rigorously defend its position," the French team added.