Index: NVDataMgmt.c
===================================================================
diff -u -r7c59cd887d070b86c0c7d6681a29a3455562c38e -rbdcb684d0519521e50bbc44e6ac276d4d851825e
--- NVDataMgmt.c	(.../NVDataMgmt.c)	(revision 7c59cd887d070b86c0c7d6681a29a3455562c38e)
+++ NVDataMgmt.c	(.../NVDataMgmt.c)	(revision bdcb684d0519521e50bbc44e6ac276d4d851825e)
@@ -2734,6 +2734,13 @@
 
         activateAlarmNoData( ALARM_ID_DG_INVALID_SYSTEM_RECORD_CRC );
     }
+    else
+    {
+        if ( RECORD_DEFAULT_CHARACTER == dgSystemGroup.dgSystemRecord.topLevelSN[ 0 ] )
+        {
+            activateAlarmNoData( ALARM_ID_DG_INVALID_SERIAL_NUMBER );
+        }
+    }
 
     return status;
 }
Index: NVDataMgmtDGRecords.h
===================================================================
diff -u -rb02c369dad6391be4687f99b49d169e3c212373d -rbdcb684d0519521e50bbc44e6ac276d4d851825e
--- NVDataMgmtDGRecords.h	(.../NVDataMgmtDGRecords.h)	(revision b02c369dad6391be4687f99b49d169e3c212373d)
+++ NVDataMgmtDGRecords.h	(.../NVDataMgmtDGRecords.h)	(revision bdcb684d0519521e50bbc44e6ac276d4d851825e)
@@ -32,7 +32,7 @@
 // ********** public definitions **********
 
 #define MAX_TOP_LEVEL_PN_CHARS                    10U                                                           ///< Max number of characters for top level part number.
-#define MAX_TOP_LEVEL_SN_CHARS                    15U                                                           ///< Max number of characters for top level serial number.
+#define MAX_TOP_LEVEL_SN_CHARS                    20U                                                           ///< Max number of characters for top level serial number.
 #define PRES_SENSORS_RESERVED_SPACE_COUNT         5                                                             ///< Pressure sensors reserved space count.
 #define FLOW_SENSROS_RESERVED_SPACE_COUNT         2                                                             ///< Flow sensors reserved space count.
 #define TEMP_SENSORS_RESERVED_SPACE_COUNT         2                                                             ///< Temperature sensors reserved space count.
Index: NVDataMgmtHDRecords.h
===================================================================
diff -u -r75f09f06b74c6c3b0ba67aeff6ade92fa35426d0 -rbdcb684d0519521e50bbc44e6ac276d4d851825e
--- NVDataMgmtHDRecords.h	(.../NVDataMgmtHDRecords.h)	(revision 75f09f06b74c6c3b0ba67aeff6ade92fa35426d0)
+++ NVDataMgmtHDRecords.h	(.../NVDataMgmtHDRecords.h)	(revision bdcb684d0519521e50bbc44e6ac276d4d851825e)
@@ -33,7 +33,7 @@
 // ********** public definitions **********
 
 #define MAX_TOP_LEVEL_PN_CHARS 10U                                                                             ///< Max number of characters for top level part number.
-#define MAX_TOP_LEVEL_SN_CHARS 15U                                                                             ///< Max number of characters for top level serial number.
+#define MAX_TOP_LEVEL_SN_CHARS 20U                                                                             ///< Max number of characters for top level serial number.
 
 #ifndef _RELEASE_
 /// Software configuration enums