This Preliminary Information communication provides information to the technician about vehicles that have a Service AWD message and/or flashing Rear Drive Warning Instrument Panel Cluster indicator. Technician may find no communication with Rear Differential Clutch Control Module and or Diagnostic Trouble Code C0407, C0550, or no Diagnostic Trouble Code set. Technician will need to reprogram the Rear Differential Clutch Control Module with the latest calibration in Service Programming System. Technician should be advised if Diagnostic Trouble Code C0550 is set a updating using Service Programming System to the Rear Differential Clutch Control Module with the latest calibration is a temporary solution until the update becomes available to fix this. Technician should use published Service Information diagnostics if the Diagnostic Trouble Code does not clear.
