Index: firmware/App/Modes/ModePreTreat.c
===================================================================
diff -u -r5c5ea32c4f6a79610ae1ff8e62d399d4894cc10a -rfb7b90110c095be1aa8b3ad4dc26fa21e8acc851
--- firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision 5c5ea32c4f6a79610ae1ff8e62d399d4894cc10a)
+++ firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision fb7b90110c095be1aa8b3ad4dc26fa21e8acc851)
@@ -59,6 +59,7 @@
     PRE_TREATMENT_RESERVOIR_MGMT_START_FILL_STATE,                      ///< Command DG to start filling reservoir
     PRE_TREATMENT_RESERVOIR_MGMT_FILL_CMD_RESP_STATE,                   ///< After sending fill command, process DG fill command response
     PRE_TREATMENT_RESERVOIR_MGMT_FILL_COMPLETE_STATE,                   ///< Reservoir fill has completed
+    PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE,
     PRE_TREATMENT_RESERVOIR_MGMT_WAIT_FOR_RESERVOIR_SWITCH_STATE,       ///< Wait for prime operation to switch reservoir
     PRE_TREATMENT_RESERVOIR_MGMT_COMPLETE_STATE,                        ///< Pre-treatment reservoir management complete state
     NUM_OF_PRE_TREATMENT_RESERVOIR_MGMT_STATES                          ///< Number of pre-treatments reservoir mgmt. states
@@ -110,6 +111,7 @@
 static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtFillCmdState( void );
 static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtFillCmdRespState( void );
 static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtFillCompleteState( void );
+static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtRequestReservoirSwitchState( void );
 static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtWaitReservoirSwitchState( void );
 static U32 getPreTreatmentFillVolume( DG_RESERVOIR_ID_T inactiveRes );
 
@@ -924,6 +926,10 @@
             currentReservoirMgmtState = handlePreTreatmentReservoirMgmtFillCompleteState();
             break;
 
+        case PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE:
+            currentReservoirMgmtState = handlePreTreatmentReservoirMgmtRequestReservoirSwitchState();
+            break;
+
         case PRE_TREATMENT_RESERVOIR_MGMT_WAIT_FOR_RESERVOIR_SWITCH_STATE:
             currentReservoirMgmtState = handlePreTreatmentReservoirMgmtWaitReservoirSwitchState();
             break;
@@ -1049,8 +1055,8 @@
 
             if ( ( initialReservoirDrain[ activeReservoir ] != TRUE ) || ( inactiveReservoir != DG_RESERVOIR_2 ) )
             {
-                cmdSetDGActiveReservoir( inactiveReservoir );
-                state = PRE_TREATMENT_RESERVOIR_MGMT_DRAIN_CMD_STATE;
+                //cmdSetDGActiveReservoir( inactiveReservoir );
+                state = PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE;
             }
         }
         else
@@ -1135,7 +1141,7 @@
         {
             if ( FALSE == reservoirFilledStatus[ DG_RESERVOIR_1 ] )
             {
-                state = PRE_TREATMENT_RESERVOIR_MGMT_WAIT_FOR_RESERVOIR_SWITCH_STATE;
+                state = PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE;
                 reservoirFilledStatus[ DG_RESERVOIR_1 ] = TRUE;
             }
             else
@@ -1149,7 +1155,7 @@
         }
         else
         {
-            state = PRE_TREATMENT_RESERVOIR_MGMT_WAIT_FOR_RESERVOIR_SWITCH_STATE;
+            state = PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE;
 
             if ( FALSE == reservoirFlushedStatus[ DG_RESERVOIR_1 ] )
             {
@@ -1162,13 +1168,13 @@
 #endif
                 {
                     reservoirFlushedStatus[ DG_RESERVOIR_1 ] = TRUE;
-                    cmdSetDGActiveReservoir( DG_RESERVOIR_1 );
+                    //cmdSetDGActiveReservoir( DG_RESERVOIR_1 );
                 }
             }
             else
             {
                 reservoirFlushedStatus[ DG_RESERVOIR_2 ] = TRUE;
-                cmdSetDGActiveReservoir( DG_RESERVOIR_2 );
+                //cmdSetDGActiveReservoir( DG_RESERVOIR_2 );
             }
         }
     }
@@ -1178,6 +1184,32 @@
 
 /*********************************************************************//**
  * @brief
+ * The handlePreTreatmentReservoirMgmtRequestReservoirSwitchState function waits
+ * until prime operation switches the active reservoir before filling up next reservoir.
+ * @details Inputs: DG intactive reservoir
+ * @details Outputs: start filling next reservoir
+ * @return current state of pre-treatment reservoir management
+ *************************************************************************/
+static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtRequestReservoirSwitchState( void )
+{
+    PRE_TREATMENT_RESERVOIR_MGMT_STATE_T state = PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE;
+    DG_OP_MODE_T dgOpMode = getDGOpMode();
+    U32 dgSubMode = getDGSubMode();
+    DG_RESERVOIR_ID_T inactiveReservoir = getDGInactiveReservoir();
+
+    //wait after drain or fill
+    if ( ( DG_MODE_GENE == dgOpMode ) && ( DG_GEN_IDLE_MODE_STATE_FLUSH_WATER == dgSubMode ) )
+    {
+        state = PRE_TREATMENT_RESERVOIR_MGMT_WAIT_FOR_RESERVOIR_SWITCH_STATE;
+        cmdSetDGActiveReservoir( inactiveReservoir );
+    }
+
+    return state;
+}
+
+
+/*********************************************************************//**
+ * @brief
  * The handlePreTreatmentReservoirMgmtWaitReservoirSwitchState function waits
  * until prime operation switches the active reservoir before filling up next reservoir.
  * @details Inputs: DG intactive reservoir
@@ -1187,7 +1219,26 @@
 static PRE_TREATMENT_RESERVOIR_MGMT_STATE_T handlePreTreatmentReservoirMgmtWaitReservoirSwitchState( void )
 {
     PRE_TREATMENT_RESERVOIR_MGMT_STATE_T state = PRE_TREATMENT_RESERVOIR_MGMT_WAIT_FOR_RESERVOIR_SWITCH_STATE;
+    DG_CMD_RESPONSE_T dgCmdResp;
+    // handle fill command response from DG
+    if ( TRUE == getDGCommandResponse( DG_CMD_SWITCH_RESERVOIR, &dgCmdResp ) )
+    {
+        if ( DG_CMD_REQUEST_REJECT_REASON_INVALID_MODE == dgCmdResp.rejectCode )
+        {
+            //retry?
+            state = PRE_TREATMENT_RESERVOIR_MGMT_REQUEST_RESERVOIR_SWITCH_STATE;
+        }
+        else if ( dgCmdResp.rejectCode != DG_CMD_REQUEST_REJECT_REASON_NONE )
+        {// bad call
+            SET_ALARM_WITH_2_U32_DATA( ALARM_ID_HD_SOFTWARE_FAULT, SW_FAULT_ID_DG_INVALID_FILL_COMMAND_REJECTED, dgCmdResp.rejectCode )
+        }
+        else
+        {// success. move forward
+            state = PRE_TREATMENT_RESERVOIR_MGMT_DRAIN_CMD_STATE;
+        }
+    }
 
+    /*
     if ( ( TRUE == reservoirFilledStatus[ DG_RESERVOIR_1 ] ) && ( FALSE == reservoirFilledStatus[ DG_RESERVOIR_2 ] ) )
     {
         if ( DG_RESERVOIR_2 == getDGInactiveReservoir() )
@@ -1201,7 +1252,7 @@
         {
             state = PRE_TREATMENT_RESERVOIR_MGMT_DRAIN_CMD_STATE;
         }
-    }
+    }*/
 
     return state;
 }