DTC C1503-01: TCS Switch Error: General Description
WARNING: This page is about a different car, the 2021 Kia Soul. However, it is still accessible from the selected car via links, so may be relevant.
Driver can inhibit the ESC/ESP control by ESC/ESP switch.
When switch signal sends into the ESC, the ESC/ESP warning lamp goes "ON" and the ESC/ESP control is stopped and if the next switch signal is inputted again, the ESC/ESP control is ready. This function is used for sporty driving or vehicle inspection.