Related to locking the vehicle or something similar.
In the decompiled scripts, its always called after
VEHICLE::_SET_EXCLUSIVE_DRIVER(a_0, 0, 0);
VEHICLE::SET_VEHICLE_DOORS_LOCKED_FOR_ALL_PLAYERS(a_0, 1);
VEHICLE::SET_VEHICLE_DOORS_LOCKED_FOR_PLAYER(a_0, PLAYER::PLAYER_ID(), 0);