Index: firmware/App/Modes/FPModes/FPModeStandby.c
===================================================================
diff -u -rd79faa7118db6d048ce3433224b3e5a478c97a98 -r3e1af7cc2576e347ab8bdf2f400196b2301def07
--- firmware/App/Modes/FPModes/FPModeStandby.c	(.../FPModeStandby.c)	(revision d79faa7118db6d048ce3433224b3e5a478c97a98)
+++ firmware/App/Modes/FPModes/FPModeStandby.c	(.../FPModeStandby.c)	(revision 3e1af7cc2576e347ab8bdf2f400196b2301def07)
@@ -1,17 +1,17 @@
 /**************************************************************************
 *
-* Copyright (c) 2024-2024 Diality Inc. - All Rights Reserved.
+* Copyright (c) 2025-2026 Diality Inc. - All Rights Reserved.
 *
 * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 *
 * @file    FPModeStandby.c
 *
-* @author  (last)      Michael Garthwaite
-* @date    (last)      28-Feb-2025
+* @author  (last)      Raghu Kallala
+* @date    (last)      31-Mar-2026
 *
 * @author  (original)  Michael Garthwaite
-* @date    (original)  28-Feb-2025
+* @date    (original)  08-Sep-2025
 *
 ***************************************************************************/
 
@@ -20,6 +20,7 @@
 #include "FPOperationModes.h"
 #include "ModePreGenPermeateDefeatured.h"
 #include "ModePreGenPermeate.h"
+#include "PermeateTank.h"
 #include "PersistentAlarm.h"
 #include "ROPump.h"
 #include "SystemCommDD.h"
@@ -65,6 +66,7 @@
 {
     initFPStandbyMode();
 
+    resetPermeateTank();
     setValveState( M4_VALV,VALVE_STATE_CLOSED );
     setValveState( M12_VALV, VALVE_STATE_CLOSED );
     setValveState( P6_VALV,VALVE_STATE_CLOSED );
@@ -144,4 +146,56 @@
  *************************************************************************/
 
 
+/*********************************************************************//**
+ * @brief
+ * The testValidateStandbyChangeReq function validate whether
+ * requested sub mode change is legal or not.
+ * @details \b Inputs: none
+ * @details \b Outputs: none
+ * @param newSubMode the enumerated sub state of the mode.
+ * @return TRUE if request is legal, FALSE if not.
+ *************************************************************************/
+BOOL testValidateStandbyChangeReq( U32 newSubMode )
+{
+    BOOL result = FALSE;
+
+    if ( newSubMode < NUM_OF_FP_STANDBY_MODE_STATES )
+    {
+        switch ( newSubMode )
+        {
+            case FP_STANDBY_MODE_STATE_IDLE:
+            default:
+                result = TRUE;
+                break;
+        }
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The testSignalNewStandbySubMode function requests transition
+ * to a new standby sub mode.
+ * @details \b Inputs: none
+ * @details \b Outputs: standbyState
+ * @param newSubMode the enumerated sub state of the mode.
+ * @return none
+ *************************************************************************/
+void testSignalNewStandbySubMode( U32 newSubMode )
+{
+    if ( newSubMode < NUM_OF_FP_STANDBY_MODE_STATES )
+    {
+        standbyState = (FP_STANDBY_MODE_STATE_T)newSubMode;
+        // handle the prerequisite if any
+        switch ( newSubMode )
+        {
+            // Any of these state require no special handling
+            case FP_STANDBY_MODE_STATE_IDLE:
+            default:
+                break;
+        }
+    }
+}
+
 /**@}*/