DTC C1603-98: ECU Thermal Protection: General Description
WARNING: This page is about a different car, the 2021 Kia Seltos. However, it is still accessible from the selected car via links, so may be relevant.
The Motor Driven Power Steering (MDPS) unit monitors that operating voltage supplied to the power supply terminal. If excessive high or low voltage is detected, the MDPS stops the current supply to the solenoid to prevent unexpected operation or damage.