diff --git a/Firmware/Marlin_main.cpp b/Firmware/Marlin_main.cpp
index 30a4258ed..276d1c7b2 100644
--- a/Firmware/Marlin_main.cpp
+++ b/Firmware/Marlin_main.cpp
@@ -5808,10 +5808,10 @@ Sigma_Exit:
     case 200: // M200 D<millimeters> set filament diameter and set E axis units to cubic millimeters (use S0 to set back to millimeters).
       {
 
-        tmp_extruder = active_extruder;
+        uint8_t extruder = active_extruder;
         if(code_seen('T')) {
-          tmp_extruder = code_value();
-		  if(tmp_extruder >= EXTRUDERS) {
+          extruder = code_value();
+		  if(extruder >= EXTRUDERS) {
             SERIAL_ECHO_START;
             SERIAL_ECHO(_i("M200 Invalid extruder "));////MSG_M200_INVALID_EXTRUDER c=0 r=0
             break;
@@ -5825,7 +5825,7 @@ Sigma_Exit:
 			// for all extruders
 		    volumetric_enabled = false;
 		  } else {
-            filament_size[tmp_extruder] = (float)code_value();
+            filament_size[extruder] = (float)code_value();
 			// make sure all extruders have some sane value for the filament size
 			filament_size[0] = (filament_size[0] == 0.0 ? DEFAULT_NOMINAL_FILAMENT_DIA : filament_size[0]);
             #if EXTRUDERS > 1
diff --git a/Firmware/mmu.cpp b/Firmware/mmu.cpp
index a48ca36a8..963f3da3e 100644
--- a/Firmware/mmu.cpp
+++ b/Firmware/mmu.cpp
@@ -28,12 +28,13 @@ bool mmu_enabled = false;
 
 bool mmu_ready = false;
 
-int8_t mmu_state = 0;
+static int8_t mmu_state = 0;
 
 uint8_t mmu_cmd = 0;
 
 uint8_t mmu_extruder = 0;
 
+//! This variable probably has no meaning and is planed to be removed
 uint8_t tmp_extruder = 0;
 
 int8_t mmu_finda = -1;
@@ -363,29 +364,27 @@ void mmu_load_to_nozzle()
 void mmu_M600_load_filament(bool automatic)
 { 
 	//load filament for mmu v2
-		  bool yes = false;
+		  uint8_t filament = mmu_extruder;
 		  if (!automatic) {
-			  yes = lcd_show_fullscreen_message_yes_no_and_wait_P(_i("Do you want to switch extruder?"), false);
-			  if(yes) tmp_extruder = choose_extruder_menu();
-			  else tmp_extruder = mmu_extruder;
-
+		      bool yes = lcd_show_fullscreen_message_yes_no_and_wait_P(_i("Do you want to switch extruder?"), false);
+			  if(yes) filament = choose_extruder_menu();
 		  }
 		  else {
-			  tmp_extruder = (tmp_extruder+1)%5;
+			  filament = (filament+1)%5;
 		  }
 		  lcd_update_enable(false);
 		  lcd_clear();
 		  lcd_set_cursor(0, 1); lcd_puts_P(_T(MSG_LOADING_FILAMENT));
 		  lcd_print(" ");
-		  lcd_print(tmp_extruder + 1);
-		  snmm_filaments_used |= (1 << tmp_extruder); //for stop print
+		  lcd_print(filament + 1);
+		  snmm_filaments_used |= (1 << filament); //for stop print
 
-//		  printf_P(PSTR("T code: %d \n"), tmp_extruder);
-//		  mmu_printf_P(PSTR("T%d\n"), tmp_extruder);
-		  mmu_command(MMU_CMD_T0 + tmp_extruder);
+//		  printf_P(PSTR("T code: %d \n"), filament);
+//		  mmu_printf_P(PSTR("T%d\n"), filament);
+		  mmu_command(MMU_CMD_T0 + filament);
 
 		  manage_response(false, true);
-    	  mmu_extruder = tmp_extruder; //filament change is finished
+    	  mmu_extruder = filament; //filament change is finished
 
 		  mmu_load_to_nozzle();
 
diff --git a/Firmware/mmu.h b/Firmware/mmu.h
index 763c15ea8..63835ca85 100644
--- a/Firmware/mmu.h
+++ b/Firmware/mmu.h
@@ -5,8 +5,6 @@
 
 extern bool mmu_enabled;
 
-extern int8_t mmu_state;
-
 extern uint8_t mmu_extruder;
 
 extern uint8_t tmp_extruder;