DTC U0122-87: Communication Error With DSC HU/Cm [Adaptive Front Lighting System (AFS) Control Module (Us)]

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U0122: 87 (ALH/AFS/ALV) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Communication error with electronically controlled brake unit/DSC HU/CM
Detection condition	The auto leveling control module/adaptive front lighting system (AFS) control module/adaptive LED headlights control module cannot receive CAN signal from the electronically controlled brake unit/DSC HU/CM.
Fail-safe	The headlight leveling actuator is stopped at the position when the malfunction is determined. Perform the following controls with the adaptive LED headlights turned on. (with adaptive LED headlights) Turn off glare-free high beam. Set wide-range low beam as basic light distribution.
Possible cause	Malfunction in CAN communication line between electronically controlled brake unit/DSC HU/CM and auto leveling control module/adaptive front lighting system (AFS) control module/adaptive LED headlights control module NOTE: Perform the malfunction diagnosis according to the troubleshooting procedure for the multiplex communication system. (See MALFUNCTION DIAGNOSIS FLOW [CONTROLLER AREA NETWORK (CAN)] .)
Repeatability verification procedure	Not applicable
System wiring diagram	Not applicable