We report on sensitive dual-frequency ( 1.7 and 5 GHz ) European VLBI Network observations of the central region of nine Seyfert galaxies . These sources are among the faintest and least luminous members of a complete sample of nearby ( d < 22 Mpc ) low luminosity AGNs . We detect radio emission on milliarcsecond scale in the nuclei of 4 galaxies , while for the other five sources we set an upper limit of < \sim 100 \mu Jy . In three sources , namely NGC 3227 , NGC 3982 , and NGC 4138 , radio emission is detected at both 1.7 and 5 GHz and it is resolved in two or more components . We describe the structural and spectral properties of these features ; we find that in each of these three nuclei there is one component with high brightness temperature ( typically T _ { B } > 10 ^ { 7.5 } K ) and flat/intermediate spectral index ( 0.3 \leq \alpha \leq 0.6 , S ( \nu ) \sim \nu ^ { - \alpha } ) , accompanied by secondary steep spectrum extended components . In these cases , non-thermal emission from jets or outflows is thus the most natural explanation . A faint feature is detected in NGC 4477 at 5 GHz ; keeping in mind the modest significance of this detection ( \sim 5 \sigma ) , we propose the hot corona as the origin of non-thermal emission , on the basis of the unrealistic magnetic field values required by synchrotron self-absorption . Finally , the five non-detected nuclei remain elusive and further observations on intermediate scales will be necessary to investigate their nature .