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Home >> Subaru >> 2021 >> WRX Base >> Repair and Diagnosis >> Accessories & Equipment >> Communication Devices >> Body Control System (Diagnostics) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC U123C: Lost Communication With High Beam Assist Control Module
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DTC U123C: Lost Communication With High Beam Assist Control Module

NOTE: When the customize setting for the high beam assist is not the same as the actual setting on the vehicle, DTC is detected. Check the customize settings. Refer to BODY CONTROL SYSTEM (DIAGNOSTICS)>USER CUSTOMIZING .