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Home >> Mazda >> 2023 >> CX-5 S Select >> Repair and Diagnosis >> Transmission >> Automatic Trans >> On-Board Diagnostic - AWD System >> DTC U0001-88/U0100-00/U0101-00/U0121-00: Communication Error [AWD Control Module] >> Notes
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DTC U0001-88/U0100-00/U0101-00/U0121-00: Communication Error [AWD Control Module]: Notes

DTC U0001:88/U0100:00/U0101:00/U0121:00 (AWD CONTROL MODULE) DETECTION CONDITION AND POSSIBLE CAUSE

DTC U0001:88 CAN system Communication error
DTC U0100:00 Communication error to PCM
DTC U0101:00 Communication error to TCM
DTC U0121:00 Communication error to DSC HU/CM
DETECTION CONDITION  
  • U0001:88
    • Open or short circuit in CAN system wiring harness is detected.
  • U0100:00
    • Communication error with PCM is detected in CAN communication.
  • U0101:00
    • Communication error with TCM is detected in CAN communication.
  • U0121:00
  • Communication error to DSC HU/CM is detected in CAN communication
FAIL-SAFE FUNCTION  
  • U0001:88, U0100:00, U0121:00
    • Control disabled.
  • U0101:00
  • Lost gear position signal: AWD operates by the specified data.
  • Except above: Control disabled.
POSSIBLE CAUSE  
  • CAN system wiring harness open or short circuit
  • CAN system wiring harness open or short circuit with PCM
  • CAN system wiring harness open or short circuit with TCM
  • CAN system wiring harness open or short circuit with DSC HU/CM
SYSTEM WIRING DIAGRAM Not applicable