Index: firmware/App/Modes/ModePreTreat.c
===================================================================
diff -u -r3d72b777cf1ceb673d118341c46e2d6d5b7b75f5 -r3d3cc1e6819f83db631270dc0fd019d15739db08
--- firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision 3d72b777cf1ceb673d118341c46e2d6d5b7b75f5)
+++ firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision 3d3cc1e6819f83db631270dc0fd019d15739db08)
@@ -263,16 +263,50 @@
  *************************************************************************/
 void signalUserConfirmInstallation( void )
 {
+    BOOL accepted = FALSE;
+    REQUEST_REJECT_REASON_CODE_T rejReason = REQUEST_REJECT_REASON_NONE;
+
+    confirmInstallRequested = FALSE;
+
     F32 bolusVol = getTreatmentParameterF32( TREATMENT_PARAM_HEPARIN_BOLUS_VOLUME );
     F32 hepRate  = getTreatmentParameterF32( TREATMENT_PARAM_HEPARIN_DISPENSE_RATE );
 
-    // Accept installation confirmation if we are in install state of pre-treatment mode and syringe is detected or Heparin not being used in this treatment.
+    // Accept installation confirmation if we are in install state of pre-treatment mode and
+    // Door closed, Cartridge installed, syringe is detected or Heparin not being used in this treatment.
     if ( ( MODE_PRET == getCurrentOperationMode() ) &&
-         ( HD_PRE_TREATMENT_CART_INSTALL_STATE == currentPreTreatmentState ) &&
-         ( ( TRUE == isSyringeDetected() ) || ( ( bolusVol < NEARLY_ZERO ) && ( hepRate < NEARLY_ZERO ) ) ) )
+         ( HD_PRE_TREATMENT_CART_INSTALL_STATE == currentPreTreatmentState ) )
     {
-        confirmInstallRequested = TRUE;
+        if ( STATE_CLOSED == getSwitchStatus( FRONT_DOOR ) )
+        {
+            if ( CONSUMABLE_SELF_TESTS_COMPLETE_STATE == getConsumableSelfTestState() )
+            {
+                if ( ( TRUE == isSyringeDetected() ) || ( ( bolusVol < NEARLY_ZERO ) && ( hepRate < NEARLY_ZERO ) ) )
+                {
+                    // Everything is properly installed
+                    accepted = TRUE;
+                    confirmInstallRequested = TRUE;
+                }
+                else
+                {
+                    rejReason = REQUEST_REJECT_REASON_SYRINGE_NOT_PRESENT;
+                }
+            }
+            else
+            {
+                rejReason = REQUEST_REJECT_REASON_CONSUMABLE_NOT_READY;
+            }
+        }
+        else
+        {
+            rejReason = REQUEST_REJECT_REASON_DOOR_NOT_CLOSED;
+        }
     }
+    else
+    {
+        rejReason = REQUEST_REJECT_REASON_ACTION_DISABLED_IN_CURRENT_STATE;
+    }
+
+    sendConsumableInstallCmdResponse( accepted, (U32) rejReason );
 }
 
 /*********************************************************************//**