Have seen this fault on many occaisions the ecu obtains information on loading from map and egr together with throttle and temp etc,very few are fitted with air mass,why it produces this air mass code is probably just French!or the software your Launch uses interprets the results in error.Most likely cause is egr as expressed by others,try clearing codes and drive without egr attatched,check plug to egr whislt removing, notorious for contamination.As suggested by Ian try resetting egr settings as though adapting in new unit.May need software updating to change egr settings will need clip to upgrade.Hth