The flight data recorder of EgyptAir flight MS804 had been successfully repaired, paving the way for investigators to analyse data that may explain its crash.
The Airbus went down in the eastern Mediterranean en route from Paris to Cairo on May 19 and all 66 people on board were killed.
Egypt air investigators said the plane's cockpit voice recorder would begin to be worked on "within hours".
The recorders arrived in Paris from Egypt on Monday to remove salt deposits and would be returned to a laboratory in Cairo to analyse the data once repairs are completed.
Meanwhile, the Paris prosecutor's office has opened a manslaughter investigation into the crash, but was not looking into terrorism as a possible cause at this stage.
Debris from the jet was brought to Cairo airport on Monday, where investigators will try to reassemble part of the plane's frame in search of morel clues that may help explain the crash, a source on the investigation committee said.
