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Home >> Mazda >> 2021 >> 6 Signature >> Repair and Diagnosis >> Accessories & Equipment >> Headlights >> On-Board Diagnostic - Auto Leveling Control Module >> DTC U0001-88/U0100-00/U0140-00/U0155-00: Unit Communication Error (HS-Can) [Auto Leveling Control Module] >> Notes
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DTC U0001-88/U0100-00/U0140-00/U0155-00: Unit Communication Error (HS-Can) [Auto Leveling Control Module]: Notes

DTC U0001:88/U0100:00/U0140:00/U0155:00 [AUTO LEVELING CONTROL MODULE] DETECTION CONDITION AND POSSIBLE CAUSE

Description
  • U0001:88
    • Unit communication error (HS-CAN)
  • U0100:00
    • Communication error with PCM
  • U0140:00
    • Communication error with front body control module (FBCM)
  • U0155:00
    • Communication error with instrument cluster
Detection condition
  • U0001:88
    • Auto leveling control module detected the CAN bus communication line (HS-CAN) malfunction 10 times continuously.
  • U0100:00
    • Auto leveling control module could not receive the CAN signal from the PCM for 5 s or more.
  • U0140:00
    • Auto leveling control module could not receive the CAN signal from the front body control module (FBCM) for 5 s or more.
  • U0155:00
    • Auto leveling control module could not receive the CAN signal from the instrument cluster for 5 s or more.
Fail-safe
  • U0001:88
    • The headlight leveling actuator is stopped at the position when the malfunction is determined.
  • U0100:00
    • The headlight leveling actuator is stopped at the position when the malfunction is determined.
  • U0140:00
    • The headlight leveling actuator is stopped at the position when the malfunction is determined.
  • U0155:00
    • Control of the headlight auto leveling system is continued.
Possible cause
  • Malfunction in CAN bus communication line
  • Malfunction in CAN communication line between PCM and auto leveling control module
  • Malfunction in CAN communication line between front body control module (FBCM) and auto leveling control module
  • Malfunction in CAN communication line between instrument cluster and auto leveling control module
System wiring diagram Not applicable