diff --git a/Firmware/ultralcd.cpp b/Firmware/ultralcd.cpp
index 12943299..7fcb576e 100644
--- a/Firmware/ultralcd.cpp
+++ b/Firmware/ultralcd.cpp
@@ -158,7 +158,26 @@ static bool lcd_selfcheck_pulleys(int axis);
 #endif //TMC2130
 
 static bool lcd_selfcheck_check_heater(bool _isbed);
-static int  lcd_selftest_screen(int _step, int _progress, int _progress_scale, bool _clear, int _delay);
+enum class testScreen
+{
+    extruderFan,
+    printFan,
+    fansOk,
+    endStops,
+    axisX,
+    axisY,
+    axisZ,
+    bed,
+    hotend,
+    hotendOk,
+    fsensor,
+    fsensorOk,
+    allCorrect,
+    failed,
+    home,
+};
+
+static int  lcd_selftest_screen(testScreen screen, int _progress, int _progress_scale, bool _clear, int _delay);
 static void lcd_selftest_screen_step(int _row, int _col, int _state, const char *_name, const char *_indicator);
 static bool lcd_selftest_manual_fan_check(int _fan, bool check_opposite);
 static bool lcd_selftest_fan_dialog(int _fan);
@@ -6295,7 +6314,7 @@ bool lcd_selftest()
 	delay(2000);
 	KEEPALIVE_STATE(IN_HANDLER);
 
-	_progress = lcd_selftest_screen(-1, _progress, 3, true, 2000);
+	_progress = lcd_selftest_screen(testScreen::extruderFan, _progress, 3, true, 2000);
 #if (defined(FANCHECK) && defined(TACH_0)) 		
 	_result = lcd_selftest_fan_dialog(0);
 #else //defined(TACH_0)
@@ -6310,7 +6329,7 @@ bool lcd_selftest()
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(0, _progress, 3, true, 2000);
+		_progress = lcd_selftest_screen(testScreen::printFan, _progress, 3, true, 2000);
 #if (defined(FANCHECK) && defined(TACH_1)) 		
 		_result = lcd_selftest_fan_dialog(1);
 #else //defined(TACH_1)
@@ -6326,7 +6345,7 @@ bool lcd_selftest()
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(1, _progress, 3, true, 2000);
+		_progress = lcd_selftest_screen(testScreen::fansOk, _progress, 3, true, 2000);
 #ifndef TMC2130
 		_result = lcd_selfcheck_endstops();
 #else
@@ -6337,7 +6356,7 @@ bool lcd_selftest()
 	if (_result)
 	{
 		//current_position[Z_AXIS] += 15;									//move Z axis higher to avoid false triggering of Z end stop in case that we are very low - just above heatbed
-		_progress = lcd_selftest_screen(3, _progress, 3, true, 2000);
+		_progress = lcd_selftest_screen(testScreen::axisX, _progress, 3, true, 2000);
 #ifdef TMC2130
         _result = lcd_selfcheck_axis_sg(X_AXIS);
 #else
@@ -6350,7 +6369,7 @@ bool lcd_selftest()
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(3, _progress, 3, true, 0);
+		_progress = lcd_selftest_screen(testScreen::axisX, _progress, 3, true, 0);
 
 #ifndef TMC2130
 		_result = lcd_selfcheck_pulleys(X_AXIS);
@@ -6360,7 +6379,7 @@ bool lcd_selftest()
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(4, _progress, 3, true, 1500);
+		_progress = lcd_selftest_screen(testScreen::axisY, _progress, 3, true, 1500);
 #ifdef TMC2130
 		_result = lcd_selfcheck_axis_sg(Y_AXIS);
 #else
@@ -6370,7 +6389,7 @@ bool lcd_selftest()
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(4, _progress, 3, true, 0);
+		_progress = lcd_selftest_screen(testScreen::axisZ, _progress, 3, true, 0);
 #ifndef TMC2130
 		_result = lcd_selfcheck_pulleys(Y_AXIS);
 #endif // TMC2130
@@ -6391,7 +6410,7 @@ bool lcd_selftest()
 		current_position[Z_AXIS] = current_position[Z_AXIS] + 10;
 		plan_buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[3], manual_feedrate[0] / 60, active_extruder);
 		st_synchronize();
-		_progress = lcd_selftest_screen(5, _progress, 3, true, 1500);
+		_progress = lcd_selftest_screen(testScreen::axisZ, _progress, 3, true, 1500);
 		_result = lcd_selfcheck_axis(2, Z_MAX_POS);
 		if (eeprom_read_byte((uint8_t*)EEPROM_WIZARD_ACTIVE) != 1) {
 			enquecommand_P(PSTR("G28 W"));
@@ -6405,11 +6424,11 @@ bool lcd_selftest()
 		current_position[Z_AXIS] = current_position[Z_AXIS] + 10;
 		plan_buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[3], manual_feedrate[0] / 60, active_extruder);
 		st_synchronize();
-		_progress = lcd_selftest_screen(13, 0, 2, true, 0);
+		_progress = lcd_selftest_screen(testScreen::home, 0, 2, true, 0);
 		bool bres = tmc2130_home_calibrate(X_AXIS);
-		_progress = lcd_selftest_screen(13, 1, 2, true, 0);
+		_progress = lcd_selftest_screen(testScreen::home, 1, 2, true, 0);
 		bres &= tmc2130_home_calibrate(Y_AXIS);
-		_progress = lcd_selftest_screen(13, 2, 2, true, 0);
+		_progress = lcd_selftest_screen(testScreen::home, 2, 2, true, 0);
 		if (bres)
 			eeprom_update_byte((uint8_t*)EEPROM_TMC2130_HOME_ENABLED, 1);
 		_result = bres;
@@ -6418,24 +6437,24 @@ bool lcd_selftest()
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(6, _progress, 3, true, 2000); //check bed
+		_progress = lcd_selftest_screen(testScreen::bed, _progress, 3, true, 2000);
 		_result = lcd_selfcheck_check_heater(true);
 	}
 
     if (_result)
     {
-        _progress = lcd_selftest_screen(7, _progress, 3, true, 1000); //check nozzle
+        _progress = lcd_selftest_screen(testScreen::hotend, _progress, 3, true, 1000);
         _result = lcd_selfcheck_check_heater(false);
     }
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(8, _progress, 3, true, 2000); //nozzle ok
+		_progress = lcd_selftest_screen(testScreen::hotendOk, _progress, 3, true, 2000); //nozzle ok
 	}
 
 #ifdef FILAMENT_SENSOR
     if (_result)
     {
-        _progress = lcd_selftest_screen(9, _progress, 3, true, 2000); //check filaments sensor
+        _progress = lcd_selftest_screen(testScreen::fsensor, _progress, 3, true, 2000); //check filaments sensor
         if (mmu_enabled)
         {
             _result = selftest_irsensor();
@@ -6446,17 +6465,17 @@ bool lcd_selftest()
     }
     if (_result)
     {
-        _progress = lcd_selftest_screen(10, _progress, 3, true, 2000); //fil sensor OK
+        _progress = lcd_selftest_screen(testScreen::fsensorOk, _progress, 3, true, 2000); //fil sensor OK
     }
 #endif // FILAMENT_SENSOR
 
 	if (_result)
 	{
-		_progress = lcd_selftest_screen(11, _progress, 3, true, 5000); //all correct
+		_progress = lcd_selftest_screen(testScreen::allCorrect, _progress, 3, true, 5000); //all correct
 	}
 	else
 	{
-		_progress = lcd_selftest_screen(12, _progress, 3, true, 5000);
+		_progress = lcd_selftest_screen(testScreen::failed, _progress, 3, true, 5000);
 	}
 	lcd_reset_alert_level();
 	enquecommand_P(PSTR("M84"));
@@ -6663,7 +6682,7 @@ static bool lcd_selfcheck_axis(int _axis, int _travel)
 		}
 		else
 		{
-			_progress = lcd_selftest_screen(3 + _axis, _progress, 3, false, 0);
+			_progress = lcd_selftest_screen(static_cast<testScreen>(static_cast<int>(testScreen::axisX) + _axis), _progress, 3, false, 0);
 			_lcd_refresh = 0;
 		}
 
@@ -6830,7 +6849,7 @@ static bool lcd_selfcheck_check_heater(bool _isbed)
 
 		manage_heater();
 		manage_inactivity(true);
-		_progress = (_isbed) ? lcd_selftest_screen(6, _progress, 2, false, 400) : lcd_selftest_screen(7, _progress, 2, false, 400);
+		_progress = (_isbed) ? lcd_selftest_screen(testScreen::bed, _progress, 2, false, 400) : lcd_selftest_screen(testScreen::hotend, _progress, 2, false, 400);
 		/*if (_isbed) {
 			MYSERIAL.print("Bed temp:");
 			MYSERIAL.println(degBed());
@@ -7040,16 +7059,16 @@ static bool selftest_irsensor()
         TempBackup tempBackup;
         setTargetHotend(ABS_PREHEAT_HOTEND_TEMP,active_extruder);
         mmu_wait_for_heater_blocking();
-        progress = lcd_selftest_screen(9, 0, 1, true, 0);
+        progress = lcd_selftest_screen(testScreen::fsensor, 0, 1, true, 0);
         mmu_filament_ramming();
     }
-    progress = lcd_selftest_screen(9, progress, 1, true, 0);
+    progress = lcd_selftest_screen(testScreen::fsensor, progress, 1, true, 0);
     mmu_command(MMU_CMD_U0);
     manage_response(false, false);
 
     for(uint_least8_t i = 0; i < 200; ++i)
     {
-        if (0 == (i % 32)) progress = lcd_selftest_screen(9, progress, 1, true, 0);
+        if (0 == (i % 32)) progress = lcd_selftest_screen(testScreen::fsensor, progress, 1, true, 0);
 
         mmu_load_step(false);
         while (blocks_queued())
@@ -7227,12 +7246,11 @@ static bool lcd_selftest_fan_dialog(int _fan)
 	return _result;
 }
 
-static int lcd_selftest_screen(int _step, int _progress, int _progress_scale, bool _clear, int _delay)
+static int lcd_selftest_screen(testScreen screen, int _progress, int _progress_scale, bool _clear, int _delay)
 {
 
     lcd_update_enable(false);
 
-	int _step_block = 0;
 	const char *_indicator = (_progress >= _progress_scale) ? "-" : "|";
 
 	if (_clear) lcd_clear();
@@ -7240,58 +7258,58 @@ static int lcd_selftest_screen(int _step, int _progress, int _progress_scale, bo
 
 	lcd_set_cursor(0, 0);
 
-	if (_step == -1) lcd_puts_P(_T(MSG_SELFTEST_FAN));
-	if (_step == 0) lcd_puts_P(_T(MSG_SELFTEST_FAN));
-	if (_step == 1) lcd_puts_P(_T(MSG_SELFTEST_FAN));
-	if (_step == 2) lcd_puts_P(_i("Checking endstops"));////MSG_SELFTEST_CHECK_ENDSTOPS c=20 r=0
-	if (_step == 3) lcd_puts_P(_i("Checking X axis  "));////MSG_SELFTEST_CHECK_X c=20 r=0
-	if (_step == 4) lcd_puts_P(_i("Checking Y axis  "));////MSG_SELFTEST_CHECK_Y c=20 r=0
-	if (_step == 5) lcd_puts_P(_i("Checking Z axis  "));////MSG_SELFTEST_CHECK_Z c=20 r=0
-	if (_step == 6) lcd_puts_P(_T(MSG_SELFTEST_CHECK_BED));
-	if (_step == 7
-	    || _step == 8) lcd_puts_P(_i("Checking hotend  "));////MSG_SELFTEST_CHECK_HOTEND c=20 r=0
-	if (_step == 9) lcd_puts_P(_T(MSG_SELFTEST_CHECK_FSENSOR));
-	if (_step == 10) lcd_puts_P(_T(MSG_SELFTEST_CHECK_FSENSOR));
-	if (_step == 11) lcd_puts_P(_i("All correct      "));////MSG_SELFTEST_CHECK_ALLCORRECT c=20 r=0
-	if (_step == 12) lcd_puts_P(_T(MSG_SELFTEST_FAILED));
-	if (_step == 13) lcd_puts_P(PSTR("Calibrating home"));
+	if (screen == testScreen::extruderFan) lcd_puts_P(_T(MSG_SELFTEST_FAN));
+	if (screen == testScreen::printFan) lcd_puts_P(_T(MSG_SELFTEST_FAN));
+	if (screen == testScreen::fansOk) lcd_puts_P(_T(MSG_SELFTEST_FAN));
+	if (screen == testScreen::endStops) lcd_puts_P(_i("Checking endstops"));////MSG_SELFTEST_CHECK_ENDSTOPS c=20 r=0
+	if (screen == testScreen::axisX) lcd_puts_P(_i("Checking X axis  "));////MSG_SELFTEST_CHECK_X c=20 r=0
+	if (screen == testScreen::axisY) lcd_puts_P(_i("Checking Y axis  "));////MSG_SELFTEST_CHECK_Y c=20 r=0
+	if (screen == testScreen::axisZ) lcd_puts_P(_i("Checking Z axis  "));////MSG_SELFTEST_CHECK_Z c=20 r=0
+	if (screen == testScreen::bed) lcd_puts_P(_T(MSG_SELFTEST_CHECK_BED));
+	if (screen == testScreen::hotend
+	    || screen == testScreen::hotendOk) lcd_puts_P(_i("Checking hotend  "));////MSG_SELFTEST_CHECK_HOTEND c=20 r=0
+	if (screen == testScreen::fsensor) lcd_puts_P(_T(MSG_SELFTEST_CHECK_FSENSOR));
+	if (screen == testScreen::fsensorOk) lcd_puts_P(_T(MSG_SELFTEST_CHECK_FSENSOR));
+	if (screen == testScreen::allCorrect) lcd_puts_P(_i("All correct      "));////MSG_SELFTEST_CHECK_ALLCORRECT c=20 r=0
+	if (screen == testScreen::failed) lcd_puts_P(_T(MSG_SELFTEST_FAILED));
+	if (screen == testScreen::home) lcd_puts_P(_i("Calibrating home"));////c=20 r=1
 
 	lcd_set_cursor(0, 1);
 	lcd_puts_P(separator);
-	if ((_step >= -1) && (_step <= 1))
+	if ((screen >= testScreen::extruderFan) && (screen <= testScreen::fansOk))
 	{
 		//SERIAL_ECHOLNPGM("Fan test");
 		lcd_puts_at_P(0, 2, _i("Extruder fan:"));////MSG_SELFTEST_EXTRUDER_FAN_SPEED c=18 r=0
 		lcd_set_cursor(18, 2);
-		(_step < 0) ? lcd_print(_indicator) : lcd_print("OK");
+		(screen < testScreen::printFan) ? lcd_print(_indicator) : lcd_print("OK");
 		lcd_puts_at_P(0, 3, _i("Print fan:"));////MSG_SELFTEST_PRINT_FAN_SPEED c=18 r=0
 		lcd_set_cursor(18, 3);
-		(_step < 1) ? lcd_print(_indicator) : lcd_print("OK");
+		(screen < testScreen::fansOk) ? lcd_print(_indicator) : lcd_print("OK");
 	}
-	else if (_step >= 9 && _step <= 10)
+	else if (screen >= testScreen::fsensor && screen <= testScreen::fsensorOk)
 	{
 		lcd_puts_at_P(0, 2, _i("Filament sensor:"));////MSG_SELFTEST_FILAMENT_SENSOR c=18 r=0
 		lcd_set_cursor(18, 2);
-		(_step == 9) ? lcd_print(_indicator) : lcd_print("OK");
+		(screen == testScreen::fsensor) ? lcd_print(_indicator) : lcd_print("OK");
 	}
-	else if (_step < 9)
+	else if (screen < testScreen::fsensor)
 	{
 		//SERIAL_ECHOLNPGM("Other tests");
 
-		_step_block = 3;
-		lcd_selftest_screen_step(2, 2, ((_step == _step_block) ? 1 : (_step < _step_block) ? 0 : 2), "X", _indicator);
+	    testScreen _step_block = testScreen::axisX;
+		lcd_selftest_screen_step(2, 2, ((screen == _step_block) ? 1 : (screen < _step_block) ? 0 : 2), "X", _indicator);
 
-		_step_block = 4;
-		lcd_selftest_screen_step(2, 8, ((_step == _step_block) ? 1 : (_step < _step_block) ? 0 : 2), "Y", _indicator);
+		_step_block = testScreen::axisY;
+		lcd_selftest_screen_step(2, 8, ((screen == _step_block) ? 1 : (screen < _step_block) ? 0 : 2), "Y", _indicator);
 
-		_step_block = 5;
-		lcd_selftest_screen_step(2, 14, ((_step == _step_block) ? 1 : (_step < _step_block) ? 0 : 2), "Z", _indicator);
+		_step_block = testScreen::axisZ;
+		lcd_selftest_screen_step(2, 14, ((screen == _step_block) ? 1 : (screen < _step_block) ? 0 : 2), "Z", _indicator);
 
-		_step_block = 6;
-		lcd_selftest_screen_step(3, 0, ((_step == _step_block) ? 1 : (_step < _step_block) ? 0 : 2), "Bed", _indicator);
+		_step_block = testScreen::bed;
+		lcd_selftest_screen_step(3, 0, ((screen == _step_block) ? 1 : (screen < _step_block) ? 0 : 2), "Bed", _indicator);
 
-        _step_block = 7;
-        lcd_selftest_screen_step(3, 9, ((_step == _step_block) ? 1 : (_step < _step_block) ? 0 : 2), "Hotend", _indicator);
+        _step_block = testScreen::hotend;
+        lcd_selftest_screen_step(3, 9, ((screen == _step_block) ? 1 : (screen < _step_block) ? 0 : 2), "Hotend", _indicator);
 	}
 
 	if (_delay > 0) delay_keep_alive(_delay);