The invention relates to a process for repairing coated substrate surfaces comprising the following successive steps: a) optionally, preparing a blemished area to be repaired, b) providing at least one backing film coated on one side with an uncured or at least only partially cured coating layer of a thermally curable coating composition, c) applying the at least one backing film with its coated side onto the blemished area to be repaired, d) supplying thermal energy to the coating applied in this manner onto the blemished area to be repaired and e) removing the at least one backing film, whereinthe supply of thermal energy onto the coating proceeds through the at least one backing film, and/or after removal of the at least one backing film.