Index: firmware/App/Modes/ConsumableSelfTest.c
===================================================================
diff -u -r38355442b06187fe5d57deca647b3adf2fa26b89 -r3970ba21aa2500f662620ef3d4b3e1e7a48fc47a
--- firmware/App/Modes/ConsumableSelfTest.c	(.../ConsumableSelfTest.c)	(revision 38355442b06187fe5d57deca647b3adf2fa26b89)
+++ firmware/App/Modes/ConsumableSelfTest.c	(.../ConsumableSelfTest.c)	(revision 3970ba21aa2500f662620ef3d4b3e1e7a48fc47a)
@@ -72,7 +72,7 @@
     signalDialInPumpHardStop();
     signalDialOutPumpHardStop();
     stopSyringePump();
-    setCurrentSubState( (U32)currentConsumableSelfTestState );
+    setCurrentSubState( (U32)CONSUMABLE_SELF_TESTS_INSTALL_STATE );
 
     // Set valves to default positions
     setValveAirTrap( STATE_CLOSED );
Index: firmware/App/Modes/ModePostTreat.c
===================================================================
diff -u -r38355442b06187fe5d57deca647b3adf2fa26b89 -r3970ba21aa2500f662620ef3d4b3e1e7a48fc47a
--- firmware/App/Modes/ModePostTreat.c	(.../ModePostTreat.c)	(revision 38355442b06187fe5d57deca647b3adf2fa26b89)
+++ firmware/App/Modes/ModePostTreat.c	(.../ModePostTreat.c)	(revision 3970ba21aa2500f662620ef3d4b3e1e7a48fc47a)
@@ -153,7 +153,7 @@
     signalBloodPumpHardStop();
     signalDialOutPumpHardStop();
     signalDialInPumpHardStop();
-    setCurrentSubState( currentPostTreatmentState );
+    setCurrentSubState( NO_SUB_STATE );
     collectTreatmentLogData();
 
     exitBloodLeakNormalState();
Index: firmware/App/Modes/OperationModes.c
===================================================================
diff -u -r067fc27c9f9a87c7388d0f1438a7cecd7418170b -r3970ba21aa2500f662620ef3d4b3e1e7a48fc47a
--- firmware/App/Modes/OperationModes.c	(.../OperationModes.c)	(revision 067fc27c9f9a87c7388d0f1438a7cecd7418170b)
+++ firmware/App/Modes/OperationModes.c	(.../OperationModes.c)	(revision 3970ba21aa2500f662620ef3d4b3e1e7a48fc47a)
@@ -61,7 +61,8 @@
 static HD_OP_MODE_T currentMode;                            ///< Current operation mode.
 static U32 currentSubMode;                                  ///< The currently active state of the active mode.
 static U32 broadcastModeIntervalCtr;                        ///< Interval counter used to determine when to broadcast operation mode.  Initialize to 11 to stagger broadcast.
-static U32 currentSubState;
+static U32 currentSubState;                                 ///< current sub state.
+static U32 current4thLevelState;                            ///< current 4th level state.
 /// Interval (in task intervals) at which to publish operation mode data to CAN bus.
 static OVERRIDE_U32_T opModePublishInterval = { BROADCAST_HD_OP_MODE_INTERVAL, BROADCAST_HD_OP_MODE_INTERVAL, BROADCAST_HD_OP_MODE_INTERVAL, 0 };
 /// Local structure init for saving confirmation requests
@@ -112,7 +113,8 @@
     lastMode                 = MODE_INIT;
     currentMode              = MODE_INIT;
     currentSubMode           = 0;
-    currentSubState          = 0xFF;
+    currentSubState          = NO_SUB_STATE;
+    current4thLevelState     = NO_SUB_STATE;
     broadcastModeIntervalCtr = DATA_PUBLISH_COUNTER_START_COUNT;
 
     transitionToNewOperationMode( MODE_INIT );
@@ -141,6 +143,7 @@
     U32 priorSubMode = currentSubMode;
     U32 priorSubState = currentSubState;
     U32 priorOpMode = (U32)currentMode;
+    U32 prior4thLevelState = current4thLevelState;
 
     // Any new mode requests?
     newMode = arbitrateModeRequest();   // Will return current mode if no pending requests
@@ -215,7 +218,8 @@
     }   // End switch
 
     // Send operation status event when appropriate
-    if ( priorOpMode != currentMode || priorSubMode != currentSubMode || priorSubState != currentSubState )
+    if ( priorOpMode != currentMode || priorSubMode != currentSubMode ||
+         priorSubState != currentSubState || prior4thLevelState != current4thLevelState )
     {
         sendOperationStatusEvent();
         SEND_EVENT_WITH_2_U32_DATA( HD_EVENT_SUB_MODE_CHANGE, priorSubMode, currentSubMode )
@@ -593,6 +597,19 @@
 
 /*********************************************************************//**
  * @brief
+ * The setCurrentSubState function sets the current subState.
+ * @details Inputs: subState
+ * @details Outputs: currentSubState
+ * @param subState the enumerated sub state.
+ * @return none
+ *************************************************************************/
+void setCurrent4thLevelState( U32 state )
+{
+    current4thLevelState = state;
+}
+
+/*********************************************************************//**
+ * @brief
  * The sendOperationStatusEvent function constructs and sends an HD operation
  * status event.
  * @details Inputs: currentMode, currentSubMode, currentSubState
@@ -606,7 +623,8 @@
     EVENT_DATA_T dat2;
     U32 opData = ( (U08)currentMode +
                  ( (U08)currentSubMode << SHIFT_8_BITS_FOR_BYTE_SHIFT ) +
-                 ( (U08)currentSubState << SHIFT_16_BITS_FOR_WORD_SHIFT ) );
+                 ( (U08)currentSubState << SHIFT_16_BITS_FOR_WORD_SHIFT ) +
+                 ( (U08)current4thLevelSate << SHIFT_24_BITS ) );
 
     dat2.dataType = EVENT_DATA_TYPE_U32;
     dat2.data.uInt.data = 0;
Index: firmware/App/Modes/OperationModes.h
===================================================================
diff -u -r067fc27c9f9a87c7388d0f1438a7cecd7418170b -r3970ba21aa2500f662620ef3d4b3e1e7a48fc47a
--- firmware/App/Modes/OperationModes.h	(.../OperationModes.h)	(revision 067fc27c9f9a87c7388d0f1438a7cecd7418170b)
+++ firmware/App/Modes/OperationModes.h	(.../OperationModes.h)	(revision 3970ba21aa2500f662620ef3d4b3e1e7a48fc47a)
@@ -53,6 +53,7 @@
 void setConfirmationRequestStatus( GENERIC_CONFIRM_ID_T requestID, CONFIRMATION_REQUEST_STATUS_T status );   // Set the confirmation request status
 GENERIC_CONFIRM_ID_T addConfirmationRequest( GENERIC_CONFIRM_ID_T requestID, GENERIC_CONFIRM_COMMAND_T requestType, U32 rejectReason );  // Add a new confirmation request
 void setCurrentSubState( U32 subState );                            // Set the current substate.
+void setCurrent4thLevelState( U32 state );                          // Set the current 4th level state.
 
 BOOL testSetOperationMode( HD_OP_MODE_T newMode );                  // Force transition to a given mode (if allowed)
 BOOL testSetOpModePublishIntervalOverride( U32 ms );
Index: firmware/App/Modes/SampleWater.c
===================================================================
diff -u -r38355442b06187fe5d57deca647b3adf2fa26b89 -r3970ba21aa2500f662620ef3d4b3e1e7a48fc47a
--- firmware/App/Modes/SampleWater.c	(.../SampleWater.c)	(revision 38355442b06187fe5d57deca647b3adf2fa26b89)
+++ firmware/App/Modes/SampleWater.c	(.../SampleWater.c)	(revision 3970ba21aa2500f662620ef3d4b3e1e7a48fc47a)
@@ -75,6 +75,7 @@
         cmdDGSampleWater( SAMPLE_WATER_CMD_FLUSH );
     }
     initSampleWater();
+    setCurrentSubState( (U32)SAMPLE_WATER_SETUP_STATE );
 }
 
 /*********************************************************************//**
Index: firmware/App/Modes/SelfTests.c
===================================================================
diff -u -r6178c7d08bb6b7efce0bc8191a01d2ec77a57858 -r3970ba21aa2500f662620ef3d4b3e1e7a48fc47a
--- firmware/App/Modes/SelfTests.c	(.../SelfTests.c)	(revision 6178c7d08bb6b7efce0bc8191a01d2ec77a57858)
+++ firmware/App/Modes/SelfTests.c	(.../SelfTests.c)	(revision 3970ba21aa2500f662620ef3d4b3e1e7a48fc47a)
@@ -681,6 +681,7 @@
 
     if ( priorSubState != currentWetSelfTestsState )
     {
+        setCurrent4thLevelState( currentWetSelfTestsState );
         SEND_EVENT_WITH_2_U32_DATA( HD_EVENT_SUB_STATE_CHANGE, priorSubState, currentWetSelfTestsState );
     }
 }