DTC C1622-86: EMS Invalid Vehicle Speed: 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 Motor Driven Power Steering (MDPS) ECU controls warning lamp by sending a signal via CAN line. After sending a message, MDPS ECU checks signal about whether other ECU receives a signal correctly. If MDPS ECU receives signal from other ECU it recognizes that a message was transmitted normally.