2021 Ford Edge SE, 4WDFACTORY OEM SERVICE PROCEDURE

DTC U0073 (DCU) - Control Module Communication Bus A Off

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DTC DESCRIPTION U0073 (DCU) - CONTROL MODULE COMMUNICATION BUS A OFF

Description:  This DTC sets when the controller area network (CAN) between the reductant dosage control module and the data link connector (DLC) is open.
Possible Causes: 
  • Communication error
Diagnostic Aids:   
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST RM .
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