How to Install the AMS 2 Pro on a P1S: Upgrade Kit 1 vs Kit 2 and Every Connection
To add an AMS 2 Pro to a P1S you need a filament buffer (or an AMS Hub for several units), a 4-pin bus cable, a 6-pin bus cable, PTFE tubes and couplers, and the Switching Adapter if you want drying. Update the firmware first, then connect the PTFE path and both cables. Last checked October 25, 2026.
This guide follows Bambu Lab’s own P1S installation page as of October 25, 2026. It is a researched guide, not a hands-on test, so compare each step with the wiki while you work.
Which kit do you need?
If you bought the P1S and AMS 2 Pro separately, you need extra parts. Bambu sells them as two upgrade kits:
- Upgrade Kit 1 is for one AMS 2 Pro. Bambu’s UK listing shows a filament buffer, a 4-pin bus cable, the AMS 2 Pro Switching Adapter, a 4-in-1 PTFE adapter (or three PTFE couplers), and PTFE tubes (one 370 mm and two 550 mm).
- Upgrade Kit 2 is for X1/P1 owners who plan to connect more than one AMS 2 Pro. Bambu’s UK listing shows an AMS Hub in place of the filament buffer, plus the same 4-pin bus cable, Switching Adapter, PTFE adapter and tubes.
- The P1S AMS 2 Pro Combo includes the printer, the AMS 2 Pro and the accessories. It comes with the AMS Hub instead of the filament buffer.
Before you start
Update the printer firmware to the latest version first. Bambu says this avoids initialization problems. Then unbox the AMS 2 Pro and check all parts are present.
Connection steps
- Place the AMS 2 Pro on top of the P1S.
- Attach the rear PTFE tube. The AMS may already have one fitted. If not, use the included tube. Remove any tape, push the tube in as far as it goes, and check it does not pull out. Put the other end into the left port of the filament buffer.
- Add the 370 mm PTFE tube. Put one end in the right port of the filament buffer and the other end in the black section of the PTFE coupler. The spring inside the buffer should move freely and not be compressed.
- Mount the filament buffer at the back of the P1S. Match the buffer’s shape to the indentation, with the tab entering the hole at the bottom. Secure it with an H2.0 Allen key and two M3 x 21.5 screws.
- Connect the coupler to the tubing that comes out of the top of the P1S and leads to the extruder. Route the PTFE tube under the spool holder, not over it.
- Connect the 4-pin bus cable. The L-shaped end goes to the 4-pin port on the back of the printer (note the locking tab). The other end goes to the bottom port of the filament buffer.
- Connect the 6-pin bus cable. One end goes to either port on the back of the AMS 2 Pro. The other end goes to the left side of the filament buffer (or the bottom of the AMS Hub).
- Plug in the Switching Adapter (only if you want drying). Connect it to the back of the AMS 2 Pro and to a power outlet. Each AMS 2 Pro used for drying needs its own adapter.
If you use several AMS units, replace the filament buffer with an AMS Hub.
Check and load
Turn on the P1S. An AMS symbol should appear in the upper right of the home screen. If it does not, check that the 4-pin and 6-pin cables are fully seated.
To load filament, lift the top cover, place the spool in a slot, push the grey feeder tab toward the rear, and insert the filament a few centimeters. The AMS 2 Pro detects it and starts pulling it in. Bambu filaments are identified by RFID. For third-party filament, set the type and color in Bambu Studio. Do not edit filament information while printing.
One thing the wiki is not consistent about
The P1S page says to use a 500 mm tube from the AMS to the buffer, while the X1/P1 drying page says 550 mm, and the UK kit listing shows 550 mm tubes. Use the tube that comes in your kit.
Where to go next
If you need to know whether you must buy the adapter, see the power adapter guide. For drying, see the AMS 2 Pro drying guide. Both are linked from the complete AMS 2 Pro guide.