Hotbed Too Cold error - but the bed is hot?

The other night, my Ender 3V3SE threw this error in the middle of a print. Loud BEEEEP that scared myself and the cat.

Now it throws it no matter what I try to do - print, level, anything. I can independently heat the bed to 100 (I work with a LOT of ABS) and it is in fact 100, checked with kitchen thermometer. I’ve checked the leveling on the bed after typing with a service rep (https://www.youtube.com/watch?v=iaExzAYR_Fo_) and run the PID calibration. What now?

Thermistor connection or broken thermistor?

Maybe? How do I check? I assume that’s part of the hotend. I have a multimeter. Is it easier to just replace the whole hotend?

A V3SE you should be able to just replace the thermistor but first check that you haven’t overtightened the screw that holds the thermistor into the hotend block. Overtightening it can break the wires. The screw should only just nip the wires not smash them. They are very easy to break, carry a spare in your toolbox, thank me later.

Does it move on its own sometimes? I haven’t touched anything like that on the printer sine I got it - it was plug and play as soon as I put it together which I like!

Check the thermistor wires also check the silicone sock. I know what my shopping list would be.

This is what mine looks like - I can’t figure out which screw is the one that holds the thermistor in place. Mine is a little different than that diagram.


(I’m going to deal with the nozzle while I have it out :D)