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DTC B134D 02: Headlight Control Signal Error: Notes

WARNING: This page is about a different car, the 2014 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.
DTC B134D 02 DETECTION CONDITION AND POSSIBLE CAUSE

Description  Headlight control signal error 
Detection condition 
  • Front body control module (FBCM) receives the error signal from the start stop unit for 5 s or more  with the ignition switched ON (engine off or on).
Fail-safe function 
  • If DTC B134D:02 is detected when the ignition is switched ON (engine off or on), the headlight LO and the TNS are illuminated.
  • If DTC B134D:02 is cleared, the headlight LO and the TNS are turned off, and the operation returns to normal.
Possible cause 
  • DTCs are stored in the start stop unit.
  • Front body control module (FBCM) malfunction
System wiring diagram  Not applicable