Venus does not have an intrinsic magnetic field. As far as I know, we don't have any really hard data on this with respect to Pluto, but I doubt that it has one either. There seems to be three factors that need to be present in order for a planet to generate a magnetic field. First you need to have a very large amount of some liquid that will conduct electricity. For Earth, this condition is met by its molten iron-nickel outer core. For Jupiter it is probably a layer of hydrogen that is so compressed that it behaves as a liquid metal. Second this liquid must circulate. Third the planet must rotate fast enough to give order to the circulation. These factors promote the existence of electrical currents in the in the liquid that in turn generate magnetic fields. If the circulation in the liquid is random, then orientation of the field will be random and they will tend to cancel each other out. However, if circulation is controlled by the spin of the planet, then the circulation cells will tend to be aligned by the planets spin and, therefore, so will the magnetic fields. Therefore they will complement each other. The main reason why Venus does not have an intrinsic magnetic field is probably because it is spinning too slowly to organize the circulation in its outer core. The reason I say that Pluto probably does not have a magnetic field is because it appears to be made entirely of ices. There probably isn't any liquid to either circulate or conduct electricity in its makeup.