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Home >> Mazda >> 2024 >> CX-30 Premium >> Repair and Diagnosis >> 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)]
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DTC U0122-87: Communication Error With DSC HU/Cm [Adaptive Front Lighting System (AFS) Control Module (Us)]

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
  1. 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:
Repeatability verification procedure
  • Not applicable
System wiring diagram
  • Not applicable