Bed temperature never reaches target at higher levels on P1S

I have a P1S with an AMS. I usually print PLA, and when I do the bed reaches the desired temperature (55 degrees) as expected, and the print proceeds.

Trying to print PETG for the first time today, the bed never reached the target 70 degrees and the print process did not proceed past the bed preheating stage. Repeated attempts, including after powercycling the printer, gave the same result.

Testing this outside of the print startup process, I’ve manually set the desired bed temperature to 70 and 75 degrees. In either case the bed seems to stop short of reaching the desired temperature. 68 degrees and 72 degrees respectively.

Notably, the icon that is displayed when the bed is heating up in the Handy app disappears at this temperature, so it’s like the printer thinks it’s at the correct temperature even though it isn’t.

Has anyone else experienced this? If this were a kit I’d built I’d suspect that the PID tuning is off and re-calibrate, but I don’t think I can do that with the P1S.

That is quite unusual. It should reach those temperatures with ease.
If manually heating the bed is not working, you can rule out the slicer config.
Since it is actually heating it’s not likely a connector issue.

Time to contact support.

I had a couple more attempts at this and I think the problem I’m seeing is actually this bug: [*Issue*] Failed to get AMS mapping table · Issue #171 · bambulab/Bambu-Handy · GitHub

Waiting long enough after starting the print from the mobile app gave me the error discussed in that link. Sending the same file directly from the slicer worked as expected.