My Mk2 bed is much cooler in the middle than the edges
If I try to set it to ABS temperatures, it gives RUNAWAY error.
The edges reach 110 degrees and the center is 50-60.
What is going on?
I should add that the cold part is really small and right in the middle. I'm using an IR thermometer to measure it.
Out of curiosity, how are you measuring these temperature differentials, and are you getting consistent readings? "Contactless" thermal measurement devices generally have a conical field-of-view (usually specified in the user's manual). These are sometimes quite large, requiring close proximity to measure gradients with usable accuracy. As with any measuring tool, accuracy is typically proportional to the price paid for it.
Added my comment before seeing your follow-up. If the cooler area is really small, I'd say there's a FOV anomaly with the thermometer. I'd be more concerned with the calibration of the thermometer, the thermistor, or both. A differential of 50-60 deg. C seems unlikely within a small area, just from the thermal conductivity of the bed structure consideration. Unfortunately, you may need a different thermometer to determine which is at fault. Are you having any problems with adhesion on the cooler portion of the bed? The error message is still a concern.