Attached in the documentation you can find the custom g-code to change the filament without AMS.

The 3MF file is usefull 3D model to test easly the color filament change.

How it works

When there is a color change (both at a layer change or a mid layer change) the g-code:

• put the printer in pause
• unload the filament
• set a lower temperature of the hotend
• wait until you put the new color in place and push “start”
• set the right temperature of the hotend and load the new filament
• poop
• do the prime tower step (if set)
• print che new color section

This code should be added as a new preset print profile in BambuStudio. Click to edit the preset (highlighted in the first screenshot), then replace all the code in the highlighted box under "Change filament G-code (second screenshot)"

Save the new preset print profile with a new name, easy for you to identify it.

Important informations

1. Remeber to select the right print preset before start printing
2. Remember to check the sequence of the color change. You have to know which color put on and when
3. DO NOT push “stop” button (is near the start button) 😱

Original guide: https://www.reddit.com/r/BambuLab/comments/11gtlfp/change_filament_gcode_without_ams/