Process for improving the throwing power of an electrophoretic lacquer coating by coating metallic surfaces with a pretreatment composition containing silane/silanol/siloxane/polysiloxane, characterised in that this composition contains, in addition to water and optionally in addition to at least one organic solvent or/and at least one substance influencing the pH value, a) at least one compound a) selected from silanes, silanols, siloxanes and polysiloxanes, of which at least one of these compounds is still able to condense, and b) at least one titanium-containing, hafnium-containing, or/and zirconium-containing compound b) and also c) at least one type of cations c) selected from cations of metals of the 1st to 3rd and 5th to 8th subgroup, including lanthanides, and also from the 2nd main group of the periodic table of the elements, or/and at least one corresponding compound c), or/and d) at least one organic compound d) selected from monomers, oligomers, polymers, copolymers and block copolymers, wherein the coating freshly applied with the pretreatment composition is rinsed at least once with water, wherein optionally at least one water rinsing has a content of surfactant, and wherein after the rinsing with water an electrophoretic lacquer coating is applied, wherein the coating freshly applied with this composition is not thoroughly dried up until this rinsing, so that the at least one condensable compound a) does not strongly condense up until the rinsing of the pretreatment coating with water or/and up until the coating with an electrophoretic lacquer or/and wherein the pretreatment coating freshly applied with the pretreatment composition is not thoroughly dried up until the application of a subsequent electrophoretic lacquer coating, so that the at least one condensable compound a) does not strongly condense up until the application of the subsequent electrophoretic lacquer coating and characterised in that prior to the treatment with an aqueous silane-based pretreatment composition an aqueous treatment having a content of iron compound dissolved in water is carried out. a) at least one compound a) selected from silanes, silanols, siloxanes and polysiloxanes, of which at least one of these compounds is still able to condense, and b) at least one titanium-containing, hafnium-containing, or/and zirconium-containing compound b) and also c) at least one type of cations c) selected from cations of metals of the 1st to 3rd and 5th to 8th subgroup, including lanthanides, and also from the 2nd main group of the periodic table of the elements, or/and at least one corresponding compound c), or/and d) at least one organic compound d) selected from monomers, oligomers, polymers, copolymers and block copolymers, wherein the coating freshly applied with the pretreatment composition is rinsed at least once with water, wherein optionally at least one water rinsing has a content of surfactant, and wherein after the rinsing with water an electrophoretic lacquer coating is applied, wherein the coating freshly applied with this composition is not thoroughly dried up until this rinsing, so that the at least one condensable compound a) does not strongly condense up until the rinsing of the pretreatment coating with water or/and up until the coating with an electrophoretic lacquer or/and wherein the pretreatment coating freshly applied with the pretreatment composition is not thoroughly dried up until the application of a subsequent electrophoretic lacquer coating, so that the at least one condensable compound a) does not strongly condense up until the application of the subsequent electrophoretic lacquer coating and characterised in that prior to the treatment with an aqueous silane-based pretreatment composition an aqueous treatment having a content of iron compound dissolved in water is carried out.