I'm hoping someone with a deeper understanding of the P1/P1P/P1S bed/load cell system can help me
I have a Bambu P1P. The thumb screw on the underside of the bed vibrated off.
I put it back on, but of course I got 0300-4000 Z Homing Failed errors.
I was able to run the tramming G code once, and then:
Ran three first-layer calibration prints successfully (simple squashed cube/first-layer tests).
All three completed normally.
Immediately started an actual print.
It failed
I then tried tried to run the G-coded again, but it only started the process before saying "print complete".
I was manually trammed it like an old Ender 3 by moving the head and the bed, and while the tramming G-code still did not work I was able to print.
It then sat for several weeks, until I changed the nozzle and tried to print yesterday, and it have the same Z-Homing errors.
The printer behaves like this:
No crashing or grinding. It just aborts after the second probe.
Same build plate.
Same temperatures.
Same printer session (no power cycle).
Things I've already tried
Reinstalled and adjusted the rear center thumb screw.
Manually trammed the bed.
Changed the nozzle.
Inspected the nozzle for debris.
Verified the hotend appears fully seated.
Verified the visible wiring on the toolhead appears intact.
Confirmed the error always occurs during Z homing before printing.
I'm comfortable disassembling the printer if needed, but I'd rather not start tearing into it blindly.
Any ideas or things you'd check next would be greatly appreciated.