DTC U0198: Lost Communication With Telematic Control Module: General Description
WARNING: This page is about a different car, the 2015 Kia Soul EV. However, it is still accessible from the selected car via links, so may be relevant.
CAN communication is the circuit consisting of LOW line, HIGH communication line and two 120Ω resistances (installed in EPCU and CLU) that allows control modules (EPCU, LDC, VCU, BMS, TCS, AHB, EWP, FATC, TMU, OBC, etc) to exchange information to each other.