Enabling fan on auto PID tune

Since a custom fan duct caused the heat block on my printer to cool down enough to have a negative impact on PETG printing, I adjusted the auto PID tune aswell as the default PID values.

Also adding a precompiled hex file of all the previous changes.

Marlin/AnycubicTFT.cpp

@@ -203,7 +203,7 @@ void AnycubicTFTClass::HandleSpecialMenu()
     SpecialMenu=true;
   } else if (strcmp(SelectedDirectory, "<auto tune hotend pid>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: Auto Tune Hotend PID");
-    enqueue_and_echo_commands_P(PSTR("M303 E0 S230 C8 U1"));
+    enqueue_and_echo_commands_P(PSTR("M106 S178\nM303 E0 S240 C8 U1"));
   } else if (strcmp(SelectedDirectory, "<auto tune hotbed pid>")==0) {
     SERIAL_PROTOCOLLNPGM("Special Menu: Auto Tune Hotbed Pid");
     enqueue_and_echo_commands_P(PSTR("M303 E-1 S80 C8 U1"));

Marlin/Configuration.h

@@ -381,9 +381,9 @@
   // If you are using a pre-configured hotend then you can use one of the value sets by uncommenting it
 
   // i3 Mega
-  #define  DEFAULT_Kp 14.42
-  #define  DEFAULT_Ki 0.81
-  #define  DEFAULT_Kd 64.10
+  #define  DEFAULT_Kp 13.76
+  #define  DEFAULT_Ki 0.85
+  #define  DEFAULT_Kd 55.79
 
   // Ultimaker
   //#define  DEFAULT_Kp 22.2

README.md

@@ -45,6 +45,7 @@ While the i3 Mega is a great printer for it's price and produces fantastic resul
 
 - Turn on parts cooling fan, I recommend running it at 70% because of the 12V mod (`M106 S178`)
 - Send `M303 E0 S230 C8 U1` to start extruder PID auto tuning
+- Send `M303 E0 S240 C8 U1` to start extruder PID auto tuning
 - Wait for it to finish
 - Send `M303 E-1 S80 C8 U1` to start heatbed PID auto tuning
 - Wait for it to finish