diff --git a/Marlin/src/gcode/feature/pause/G61.cpp b/Marlin/src/gcode/feature/pause/G61.cpp
index 18667501e4..e0e1983a25 100644
--- a/Marlin/src/gcode/feature/pause/G61.cpp
+++ b/Marlin/src/gcode/feature/pause/G61.cpp
@@ -41,7 +41,7 @@
  *
  *   If XYZE are not given, default restore uses the smart blocking move.
  */
-void GcodeSuite::G61(void) {
+void GcodeSuite::G61() {
 
   const uint8_t slot = parser.byteval('S');
 
diff --git a/Marlin/src/lcd/TFTGLCD/lcdprint_TFTGLCD.cpp b/Marlin/src/lcd/TFTGLCD/lcdprint_TFTGLCD.cpp
index 106ce76138..d0cf5795d2 100644
--- a/Marlin/src/lcd/TFTGLCD/lcdprint_TFTGLCD.cpp
+++ b/Marlin/src/lcd/TFTGLCD/lcdprint_TFTGLCD.cpp
@@ -45,7 +45,7 @@
 
 #include <string.h>
 
-int lcd_glyph_height(void) { return 1; }
+int lcd_glyph_height() { return 1; }
 
 typedef struct _TFTGLCD_charmap_t {
   wchar_t uchar; // the unicode char
@@ -1119,7 +1119,7 @@ int lcd_put_u8str_max_P(PGM_P utf8_pstr, pixel_len_t max_length) {
     return 0;
   }
 
-  int test_TFTGLCD_charmap_all(void) {
+  int test_TFTGLCD_charmap_all() {
     int flg_error = 0;
     if (test_TFTGLCD_charmap(g_TFTGLCD_charmap_device, COUNT(g_TFTGLCD_charmap_device), "g_TFTGLCD_charmap_device", 0) < 0) {
       flg_error = 1;
diff --git a/Marlin/src/lcd/TFTGLCD/marlinui_TFTGLCD.cpp b/Marlin/src/lcd/TFTGLCD/marlinui_TFTGLCD.cpp
index 1c6b03445f..0745397f4f 100644
--- a/Marlin/src/lcd/TFTGLCD/marlinui_TFTGLCD.cpp
+++ b/Marlin/src/lcd/TFTGLCD/marlinui_TFTGLCD.cpp
@@ -265,7 +265,7 @@ void TFTGLCD::setContrast(uint16_t contrast) {
 extern volatile int8_t encoderDiff;
 
 // Read buttons and encoder states
-uint8_t MarlinUI::read_slow_buttons(void) {
+uint8_t MarlinUI::read_slow_buttons() {
   if (!PanelDetected)    return 0;
   #if ENABLED(TFTGLCD_PANEL_SPI)
     uint8_t b = 0;
diff --git a/Marlin/src/lcd/dogm/status_screen_DOGM.cpp b/Marlin/src/lcd/dogm/status_screen_DOGM.cpp
index c2174decb6..c9a44e0c64 100644
--- a/Marlin/src/lcd/dogm/status_screen_DOGM.cpp
+++ b/Marlin/src/lcd/dogm/status_screen_DOGM.cpp
@@ -61,7 +61,7 @@
   #include "../../feature/cooler.h"
 #endif
 
-#if ENABLED(I2C_AMMETER)
+#if DO_DRAW_AMMETER
   #include "../../feature/ammeter.h"
 #endif
 
diff --git a/Marlin/src/lcd/extui/anycubic_i3mega/anycubic_i3mega_lcd.cpp b/Marlin/src/lcd/extui/anycubic_i3mega/anycubic_i3mega_lcd.cpp
index 98534ba65f..729d4547a8 100644
--- a/Marlin/src/lcd/extui/anycubic_i3mega/anycubic_i3mega_lcd.cpp
+++ b/Marlin/src/lcd/extui/anycubic_i3mega/anycubic_i3mega_lcd.cpp
@@ -63,7 +63,7 @@ char AnycubicTFTClass::SelectedDirectory[30];
 char AnycubicTFTClass::SelectedFile[FILENAME_LENGTH];
 
 // Serial helpers
-static void sendNewLine(void) { LCD_SERIAL.write('\r'); LCD_SERIAL.write('\n'); }
+static void sendNewLine() { LCD_SERIAL.write('\r'); LCD_SERIAL.write('\n'); }
 static void send(const char *str) { LCD_SERIAL.print(str); }
 static void send_P(PGM_P str) {
   while (const char c = pgm_read_byte(str++))
diff --git a/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.cpp b/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.cpp
index 91746f69c4..bfa070df87 100644
--- a/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.cpp
+++ b/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.cpp
@@ -1459,7 +1459,7 @@ void DGUSScreenHandler::LanguagePInit() {
   }
 }
 
-void DGUSScreenHandler::DGUS_ExtrudeLoadInit(void) {
+void DGUSScreenHandler::DGUS_ExtrudeLoadInit() {
   ex_filament.ex_length           = distanceFilament;
   ex_filament.ex_load_unload_flag = 0;
   ex_filament.ex_need_time        = filamentSpeed_mm_s;
@@ -1469,7 +1469,7 @@ void DGUSScreenHandler::DGUS_ExtrudeLoadInit(void) {
   ex_filament.ex_tick_start       = 0;
 }
 
-void DGUSScreenHandler::DGUS_RunoutInit(void) {
+void DGUSScreenHandler::DGUS_RunoutInit() {
   #if PIN_EXISTS(MT_DET_1)
     SET_INPUT_PULLUP(MT_DET_1_PIN);
   #endif
@@ -1479,7 +1479,7 @@ void DGUSScreenHandler::DGUS_RunoutInit(void) {
   runout_mks.runout_status = UNRUNOUT_STATUS;
 }
 
-void DGUSScreenHandler::DGUS_Runout_Idle(void) {
+void DGUSScreenHandler::DGUS_Runout_Idle() {
   #if ENABLED(DGUS_MKS_RUNOUT_SENSOR)
     // scanf runout pin
     switch (runout_mks.runout_status) {
diff --git a/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.h b/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.h
index f14604d01a..dbd124cbe9 100644
--- a/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.h
+++ b/Marlin/src/lcd/extui/dgus/mks/DGUSScreenHandler.h
@@ -94,10 +94,10 @@ public:
   static void DGUS_LanguageDisplay(uint8_t var);
   static void TMC_ChangeConfig(DGUS_VP_Variable &var, void *val_ptr);
   static void GetTurnOffCtrl(DGUS_VP_Variable &var, void *val_ptr);
-  static void LanguagePInit(void);
-  static void DGUS_Runout_Idle(void);
-  static void DGUS_RunoutInit(void);
-  static void DGUS_ExtrudeLoadInit(void);
+  static void LanguagePInit();
+  static void DGUS_Runout_Idle();
+  static void DGUS_RunoutInit();
+  static void DGUS_ExtrudeLoadInit();
   static void LCD_BLK_Adjust(DGUS_VP_Variable &var, void *val_ptr);
   static void SD_FileBack(DGUS_VP_Variable &var, void *val_ptr);
 
diff --git a/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp b/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp
index fe7313b170..15b3f5adcd 100644
--- a/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp
+++ b/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp
@@ -318,7 +318,7 @@ void DGUSDisplay::ProcessRx() {
           gcode.reset_stepper_timeout();
 
           if (!vp.size) {
-            DEBUG_ECHOLN();
+            DEBUG_EOL();
             vp.rx_handler(vp, nullptr);
 
             rx_datagram_state = DGUS_IDLE;
@@ -330,18 +330,15 @@ void DGUSDisplay::ProcessRx() {
             memset(buffer, 0, vp.size);
 
             for (uint8_t i = 0; i < dlen; i++) {
-              if (i >= vp.size) {
-                break;
-              }
+              if (i >= vp.size) break;
 
-              if (i + 1 < dlen && tmp[i + 3] == 0xFF && tmp[i + 4] == 0xFF) {
+              if (i + 1 < dlen && tmp[i + 3] == 0xFF && tmp[i + 4] == 0xFF)
                 break;
-              }
 
               buffer[i] = tmp[i + 3];
             }
 
-            DEBUG_ECHOLN();
+            DEBUG_EOL();
             vp.rx_handler(vp, buffer);
 
             rx_datagram_state = DGUS_IDLE;
@@ -354,7 +351,7 @@ void DGUSDisplay::ProcessRx() {
             break;
           }
 
-          DEBUG_ECHOLN();
+          DEBUG_EOL();
           vp.rx_handler(vp, &tmp[3]);
 
           rx_datagram_state = DGUS_IDLE;
diff --git a/Marlin/src/lcd/extui/mks_ui/wifiSerial_STM32.h b/Marlin/src/lcd/extui/mks_ui/wifiSerial_STM32.h
index cf32bad396..a7281fed4a 100644
--- a/Marlin/src/lcd/extui/mks_ui/wifiSerial_STM32.h
+++ b/Marlin/src/lcd/extui/mks_ui/wifiSerial_STM32.h
@@ -39,17 +39,17 @@ class WifiSerial {
     void begin(uint32_t baud);
     void begin(uint32_t baud, uint8_t config);
     void end();
-    int available(void);
-    int read(void);
+    int available();
+    int read();
     int write(uint8_t);
 
     // Interrupt handlers
     static int _tx_complete_irq(serial_t *obj);
     static void _rx_complete_irq(serial_t *obj);
 
-    void flush(void);
-    bool isHalfDuplex(void) const;
-    void enableHalfDuplexRx(void);
+    void flush();
+    bool isHalfDuplex() const;
+    void enableHalfDuplexRx();
 
   private:
     void setRx(uint32_t _rx);
diff --git a/Marlin/src/libs/W25Qxx.cpp b/Marlin/src/libs/W25Qxx.cpp
index b458a7c965..033402d04a 100644
--- a/Marlin/src/libs/W25Qxx.cpp
+++ b/Marlin/src/libs/W25Qxx.cpp
@@ -133,7 +133,7 @@ uint16_t W25QXXFlash::W25QXX_ReadID(void) {
   return Temp;
 }
 
-void W25QXXFlash::SPI_FLASH_WriteEnable(void) {
+void W25QXXFlash::SPI_FLASH_WriteEnable() {
   // Select the FLASH: Chip Select low
   SPI_FLASH_CS_L();
   // Send "Write Enable" instruction
@@ -151,7 +151,7 @@ void W25QXXFlash::SPI_FLASH_WriteEnable(void) {
 * Output         : None
 * Return         : None
 *******************************************************************************/
-void W25QXXFlash::SPI_FLASH_WaitForWriteEnd(void) {
+void W25QXXFlash::SPI_FLASH_WaitForWriteEnd() {
   uint8_t FLASH_Status = 0;
 
   // Select the FLASH: Chip Select low
@@ -216,7 +216,7 @@ void W25QXXFlash::SPI_FLASH_BlockErase(uint32_t BlockAddr) {
 * Output         : None
 * Return         : None
 *******************************************************************************/
-void W25QXXFlash::SPI_FLASH_BulkErase(void) {
+void W25QXXFlash::SPI_FLASH_BulkErase() {
   // Send write enable instruction
   SPI_FLASH_WriteEnable();
 
diff --git a/Marlin/src/libs/W25Qxx.h b/Marlin/src/libs/W25Qxx.h
index 1133af2e74..778463477d 100644
--- a/Marlin/src/libs/W25Qxx.h
+++ b/Marlin/src/libs/W25Qxx.h
@@ -61,11 +61,11 @@ public:
   static void spi_flash_Send(uint8_t b);
   static void spi_flash_SendBlock(uint8_t token, const uint8_t *buf);
   static uint16_t W25QXX_ReadID(void);
-  static void SPI_FLASH_WriteEnable(void);
-  static void SPI_FLASH_WaitForWriteEnd(void);
+  static void SPI_FLASH_WriteEnable();
+  static void SPI_FLASH_WaitForWriteEnd();
   static void SPI_FLASH_SectorErase(uint32_t SectorAddr);
   static void SPI_FLASH_BlockErase(uint32_t BlockAddr);
-  static void SPI_FLASH_BulkErase(void);
+  static void SPI_FLASH_BulkErase();
   static void SPI_FLASH_PageWrite(uint8_t *pBuffer, uint32_t WriteAddr, uint16_t NumByteToWrite);
   static void SPI_FLASH_BufferWrite(uint8_t *pBuffer, uint32_t WriteAddr, uint16_t NumByteToWrite);
   static void SPI_FLASH_BufferRead(uint8_t *pBuffer, uint32_t ReadAddr, uint16_t NumByteToRead);