Index: firmware/App/Modes/FPModes/FPOperationModes.c
===================================================================
diff -u -rc554353ba10c84377f0b9f7218f911543a293598 -r5295636b779c5ee16f5e5b999cb2487cb8331cc7
--- firmware/App/Modes/FPModes/FPOperationModes.c	(.../FPOperationModes.c)	(revision c554353ba10c84377f0b9f7218f911543a293598)
+++ firmware/App/Modes/FPModes/FPOperationModes.c	(.../FPOperationModes.c)	(revision 5295636b779c5ee16f5e5b999cb2487cb8331cc7)
@@ -433,21 +433,29 @@
  * has a boost pump installed.
  * @details \b Inputs: none
  * @details \b Outputs: none
- * @return the rejection reason codes for stopping generate permeate.
+ * @return the rejection reason code for stopping generate permeate.
  *************************************************************************/
 REQUEST_REJECT_REASON_CODE_T signalStopGenPermeate( void )
 {
     REQUEST_REJECT_REASON_CODE_T reason = REQUEST_REJECT_REASON_NONE;
+    BOOL result = FALSE;
+
     // Stop is agnostic to defeatured/featured.
     // As long as were not in fault or POST, request to go to standby to stop
-    if ( currentMode >= FP_MODE_STAN )
+    if ( TRUE == isFPDefeatured() )
     {
-        requestNewFPOperationMode( FP_MODE_STAN );
+        result = requestPreGenDefStop();
     }
     else
     {
+        result = requestPreGenStop();
+    }
+
+    if ( FALSE == result )
+    {
         reason = REQUEST_REJECT_REASON_NOT_ALLOWED_IN_CURRENT_MODE;
     }
+
     return reason;
 }
 
@@ -457,20 +465,28 @@
  * has a boost pump installed.
  * @details \b Inputs: none
  * @details \b Outputs: none
- * @return the rejection reason codes for starting generate permeate.
+ * @return the rejection reason code for starting generate permeate.
  *************************************************************************/
 REQUEST_REJECT_REASON_CODE_T signalStartGenPermeate( void )
 {
     REQUEST_REJECT_REASON_CODE_T reason = REQUEST_REJECT_REASON_NONE;
+    BOOL result = FALSE;
+
     // TODO - Service and disinfection checks happen here.
     if ( TRUE == isFPDefeatured() )
     {
-        requestNewFPOperationMode( FP_MODE_DPGP );
+        result = requestPreGenDefStart();
     }
     else
     {
-        requestNewFPOperationMode( FP_MODE_PGEN );
+        result = requestPreGenStart();
     }
+
+    if ( FALSE == result )
+    {
+        reason = REQUEST_REJECT_REASON_NOT_ALLOWED_IN_CURRENT_MODE;
+    }
+
     return reason;
 }
 
Index: firmware/App/Modes/FPModes/ModePreGenPermeateDefeatured.c
===================================================================
diff -u -rd79faa7118db6d048ce3433224b3e5a478c97a98 -r5295636b779c5ee16f5e5b999cb2487cb8331cc7
--- firmware/App/Modes/FPModes/ModePreGenPermeateDefeatured.c	(.../ModePreGenPermeateDefeatured.c)	(revision d79faa7118db6d048ce3433224b3e5a478c97a98)
+++ firmware/App/Modes/FPModes/ModePreGenPermeateDefeatured.c	(.../ModePreGenPermeateDefeatured.c)	(revision 5295636b779c5ee16f5e5b999cb2487cb8331cc7)
@@ -285,9 +285,12 @@
 {
     BOOL result = FALSE;
 
-    result = TRUE;
-    pendingStartPreGenDefRequest = TRUE;
-    requestNewFPOperationMode( FP_MODE_DPGP );
+    if ( ( FP_MODE_STAN == getCurrentFPOperationMode() ) && ( FP_STANDBY_MODE_STATE_IDLE == getCurrentFPStandbyState() ) )
+    {
+        result = TRUE;
+        pendingStartPreGenDefRequest = TRUE;
+        requestNewFPOperationMode( FP_MODE_DPGP );
+    }
 
     return result;
 }