DTC C2112-01: Valve Relay 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.
The ESC supplies battery power to all solenoid valves with a valve relay which is controlled by the Electronic Control Unit (ECU). The valve relay and all solenoid valves are installed inside the ESC.