DTC U0121: Lost Communication with the Anti-lock Brake System (ABS) Control Module: Action

CARRY OUT an ABS module self-test. If the scan tool indicates the module is not responding, REFER to MODULE COMMUNICATIONS NETWORK to DIAGNOSE the network communication concern. If ABS module DTCs are present, REFER to ANTI-LOCK BRAKE SYSTEM - VEHICLE DYNAMIC SYSTEMS to DIAGNOSE the ABS system fault.