DTC U0121: F-CAN Malfunction (PCM-ABS Modulator-Control Unit): General Description

The controller area network (CAN) transmits/receives pulsing signals to/from the multiple control modules simultaneously by using two signal lines (CANH and CANL). When the powertrain control module (PCM) does not receive the signals from the ABS modulator-control unit via the CAN lines for a set time, the PCM detects a malfunction and stores a DTC.