Index: firmware/App/Services/SystemComm.c
===================================================================
diff -u -rf1157c760b320bf088921a25eb78e973d6341578 -r6d750c93f17571bbeba89404b63d87f37a9243af
--- firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision f1157c760b320bf088921a25eb78e973d6341578)
+++ firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 6d750c93f17571bbeba89404b63d87f37a9243af)
@@ -45,7 +45,8 @@
 #define CAN_XMIT_PACKET_TIMEOUT_MS      200     ///< If transmitted CAN frame does not cause a transmit complete interrupt within this time, re-send or move on
 #define MAX_XMIT_RETRIES                5       ///< Maximum number of retries on no transmit complete interrupt timeout
 
-#define UI_COMM_TIMEOUT_IN_MS           7500    ///< UI has not checked in for this much time
+#define UI_COMM_TIMEOUT_IN_MS           7500    ///< Maximum time (in ms) that UI is allowed to wait before checking in with HD.
+#define UI_COMM_SERVICE_MODE_TIMEOUT_IN_MS (2 * SEC_PER_MIN * MS_PER_SECOND)   ///< Maximum time (in ms) that UI is allowed to wait before checking in with HD when in service mode.
 #define DG_COMM_TIMEOUT_IN_MS           1000    ///< DG has not checked in for this much time
 
 #define MAX_COMM_CRC_FAILURES           5       ///< Maximum number of CRC errors within window period before alarm
@@ -761,10 +762,16 @@
 {
     if ( TRUE == uiDidCommunicate )
     {
-        HD_OP_MODE_T opMode = getCurrentOperationMode();
-
-        if ( TRUE == didTimeout( timeOfLastUICheckIn, UI_COMM_TIMEOUT_IN_MS ) )
+        HD_OP_MODE_T opMode  = getCurrentOperationMode();
+        U32          uiTO_MS = UI_COMM_TIMEOUT_IN_MS;
+
+        // in service mode, allow up to 2 minutes for UI to check-in (for lock-down)
+        if ( MODE_SERV == opMode )
         {
+            uiTO_MS = UI_COMM_SERVICE_MODE_TIMEOUT_IN_MS;
+        }
+        if ( TRUE == didTimeout( timeOfLastUICheckIn, uiTO_MS ) )
+        {
 #ifndef _RELEASE_
             if ( getSoftwareConfigStatus( SW_CONFIG_DISABLE_UI_COMM_ALARMS ) != SW_CONFIG_ENABLE_VALUE )
 #endif