Hi, Yesterday my P1S arrived. Unfortunately it gives me the error HMS_0500-0300-0001-0002: The toolhead is malfunctioning. I created a ticket but I don’t have the answer yet. I’m looking at the printer and I don’t know what to do since it’s new but it doesn’t work.
Welcome to the forum!
Here is the wiki that explains how to possible fix your error.
Thanks, I saw this, I have restarted several times. Since It’s new, I would not like to open it before receiving a response from support to whom I have also sent the logs.
Here the same, yesterday unboxed my p1s. Did a test Benchy and now this error. Changed the nozzle, checked the cables at the back, reboot to fabricsettings but still the same error. And the printer is only 1 day old 
Hi there. I came onto the forum with the same error that popped up last night on my P1P. I have put in a support ticket but haven’t heard back. I was printing and I had a filament jam.
I had to cut the filament (it made a knot at the entrance to the clear feeding tube) and then I had to yank it out. Then the error appeared.
I have done everything in the guide that was linked and cables are now on order. I used a multimeter to test the AP-MC cable, I have made sure every connection in the toolhead is good, and I even swapped tool heads and redid the thermal couple, and it all hasn’t worked.
The temp reading on my head drops to zero whenever I start the system (the bed is fine) and I get this error.
Anyone have any further advice. I have a tool head cable on order, as well as AP-MC cable just in case (but as I said, I traced my and it’s fine).
Just wait for the toolhead cable to arive and plug in and test?
Did this fix ur problem the new (toolhead cable) ive done the same thing u have done my printer is only 3 days old.Tried the spare nozzle etc new thermal paste still won’t raise the temp. I have read it could be the board also.
The new toolhead board fixed it.
Thanks i was looking at the TH board and the extruder interface board. so i didn’t know witch one to buy How did u determine u had the right board is there a way i can check mine before go off and buy the TH board even though im waiting on support
I waited on support and they sent a TH board.
Add me to the list of people with the Toolhead Malfunction error message as well as Firmware Upgrade required message. Mine is a brand new fresh out of the box P1S. I contacted support, gave a detailed description of the issue, and sent the log files and they replied 4 days later with instructions on how to reformat the SD card but didn’t address the toolhead malfunction. I had already followed the toolhead malfunction Wiki, and basically removed and reseated every single connector I could find on the unit, the toolhead, under the back panel, and under the front panel. I’ve done this 4 times now. Still no luck. I’ve got about 7 hours of my time in this already. It’s disappointing.
I get this similar Error message on my P2S. 0300-0200-0001-0006 and I’ve replaced the hotend assembly and went through the troubleshooting on bambulabs site all the boards light up and blink green how they say they should but the error still pops up on each restart. Not sure what to do..
Replying to my own message to provide an update. Support sent me a toolhead and a couple of cable but that didn’t fix it. then they sent a different board and a few cables.. still no luck. We stuck with it, and in the end I started just taking everything apart and examining it in detail and found a wire pinched by a screw into the frame. Removed the wire from under the screw, resealed it with liquid tape, and it is working, Bambu is sending me that component and wire to replace it or have it as a spare. While the support I received was time consuming, with it taking 3-4 days for a response every time they asked to try or swap something, in the end we did get it solved and their support was excellent at making sure I was taken care of.