[Universal]

pawn Code:

public OnPlayerEnterVehicle(playerid, vehicleid)
{
      if(vehicleid == VEHICLE_ID && ANY_OTHER_STATEMENT)
           TogglePlayerControllable(playerid, true);
      return 1;
}

You can also use SetVehicleParamsEx if you want, but then you should make another if statement, or maybe else which unlocks the vehicle.