THIS PRELIMINARY INFORMATION COMMUNICATION ADVISES THE TECHNICIAN ON STEPS TO PERFORM TO DETERMINE IF THE CUSTOMER'S BATTERY DRAIN CONCERN IS BEING CAUSED BY A KNOWN CONCERN WITH BLUETOOTH CALL TRANSFER OPERATION WHEN EXITING THE VEHICLE. IF THE CONCERN IS DUPLICATED AT THE DEALER WITH THE ONSTAR LED IS STILL GREEN AFTER THE VEHICLE IS TURNED OFF AND THE BLUETOOTH CALL WAS DISCONNECTED. DEALER SHOULD ADVISES THAT ENGINEERING IS AWARE OF THE CONCERN AND IS CURRENTLY INVESTIGATING THE ISSUE.