LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2021 >> 3 Select, 4D Hatchback, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Headlights >> On-Board Diagnostic - Adaptive Front Lighting System Control Module >> DTC U0122-87: Communication Error With DSC HU/Cm [Adaptive Front Lighting System (AFS) Control Module (Us)] >> Outline
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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

DTC U0122:87 [ADAPTIVE FRONT LIGHTING SYSTEM (AFS) CONTROL MODULE (US)] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location Communication error with DSC HU/Control Module
Detection condition
  • The adaptive front lighting system (AFS) control module cannot receive CAN signal from the DSC HU/Control Module.
Fail-safe
  • The swivel actuator is moved to the center.
  • The headlight leveling actuator is stopped at the position when the malfunction is determined.
Possible cause
  • Malfunction in CAN communication line between DSC HU/Control Module and adaptive front lighting system (AFS) control module
System wiring diagram Not applicable