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Home >> Mazda >> 2016 >> 3 Sport, 4D Sedan, Automatic Trans >> Repair and Diagnosis >> Transmission >> Transmission Control Systems >> On-Board Diagnostics - Transmission Control System >> DTC U0073-00; U0100-00; U0121-00; U0131-00; U0155-00: Can System Communication Error (HS Can) >> Notes
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DTC U0073-00; U0100-00; U0121-00; U0131-00; U0155-00: Can System Communication Error (HS Can): Notes

DTC U0073:00 CAN system communication error (HS CAN)
DETECTION CONDITION 
  • Under the following condition, a communication error (HS CAN) occurs:
    • Battery voltage is 10 V or more  .

    Diagnostic support note 

  • The check engine light does not illuminate.
  • The automatic transaxle warning light does not illuminate.
  • PENDING CODE is available.
  • FREEZE FRAME DATA is not available.
  • DTC is stored in the TCM memory.
FAIL-SAFE FUNCTION 
  • Inhibits learning control.
  • Inhibits neutral idle control.
  • Inhibits AAS.
POSSIBLE CAUSE 
  • CAN bus communication line malfunction (HS CAN)
  • TCM malfunction
SYSTEM WIRING DIAGRAM  Not applicable
DTC U0100:00 Communication error to PCM (HS CAN)
DETECTION CONDITION 
  • Under the following condition, the TCM cannot receive the signal from PCM (HS CAN)
    • Battery voltage is 10 V or more  .

    Diagnostic support note 

  • The check engine light illuminates if the TCM detects the above malfunction condition during the first drive cycle.
  • The automatic transaxle warning light does not illuminate.
  • PENDING CODE is available.
  • FREEZE FRAME DATA is available.
  • DTC is stored in the TCM memory.
FAIL-SAFE FUNCTION 
  • Inhibits learning control.
  • Inhibits neutral idle control.
  • Inhibits AAS.
POSSIBLE CAUSE 
  • CAN communication line malfunction between PCM and TCM (HS CAN)
  • TCM malfunction
SYSTEM WIRING DIAGRAM  Not applicable
DTC U0121:00 Communication error to DSC HU/CM
DETECTION CONDITION 
  • Under the following condition, the TCM cannot receive the signal from DSC HU/CM:
    • Battery voltage is 10 V or more  .

    Diagnostic support note 

  • The check engine light illuminates if the TCM detects the above malfunction condition during the first drive cycle.
  • The automatic transaxle warning light does not illuminate.
  • PENDING CODE is available.
  • FREEZE FRAME DATA is available.
  • DTC is stored in the TCM memory.
FAIL-SAFE FUNCTION 
  • Inhibits learning control.
  • Inhibits neutral idle control.
  • Inhibits AAS.
POSSIBLE CAUSE 
  • CAN communication line malfunction between TCM and DSC HU/CM
  • TCM malfunction
SYSTEM WIRING DIAGRAM  Not applicable
DTC U0131:00 Communication error to EPS control module
DETECTION CONDITION 
  • Under the following condition, the TCM cannot receive the signal from EPS control module:
    • Battery voltage is 10 V or more  .

    Diagnostic support note 

  • The check engine light does not illuminate.
  • The automatic transaxle warning light does not illuminate.
  • PENDING CODE is available.
  • FREEZE FRAME DATA is not available.
  • DTC is stored in the TCM memory.
FAIL-SAFE FUNCTION 
  • Inhibits learning control.
  • Inhibits neutral idle control.
POSSIBLE CAUSE 
  • CAN communication line malfunction between TCM and EPS control module
  • TCM malfunction
SYSTEM WIRING DIAGRAM  Not applicable
DTC U0155:00 Communication error to instrument cluster
DETECTION CONDITION 
  • Under the following condition, the TCM cannot receive the signal from instrument cluster:
    • Battery voltage is 10 V or more  .

    Diagnostic support note 

  • The check engine light illuminates if the TCM detects the above malfunction condition during the first drive cycle.
  • The automatic transaxle warning light does not illuminate.
  • PENDING CODE is available.
  • FREEZE FRAME DATA is available.
  • DTC is stored in the TCM memory.
FAIL-SAFE FUNCTION 
  • Inhibits learning control.
  • Inhibits manual mode.
  • Inhibits neutral idle control.
POSSIBLE CAUSE 
  • CAN communication line malfunction between TCM and instrument cluster
  • TCM malfunction
SYSTEM WIRING DIAGRAM  Not applicable