DTC C1816-87: CAN Time-Out SJB: 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 BCW system receives the turn signal, the tail lamp turn signal, and the automatic light control signal from the gateway and uses it for the rear side alarm control. If any one of the CAN signals received from the gateway is continuously received with a value of '3 (B-CAN timeout)', the C181687 fault code will be generated, but the system will operate normally.