[en] The dissociative ionization of CO by low energy electron impact into C+ and O (or O-) and O+ and C (or C-) is investigated using ion energy and mass analysis. The kinetic energy distributions are studied as a function of the impinging electron energy. The threshold energies of C+ and O+ are measured as a function of the released kinetic energy. The formation of the products in their ground level and with a small amount of kinetic energy mainly occurs through predissociation. The CO+ electronic states involved in these processes are tentatively identified. New evidences have been found for the importance of dissociative ionization via autoionization.