It is a Hardware problem, the buck converter that steps up the voltage from the 19V to 28V for powering the motor has failed.
The output fets of this buck converter are getting shorted due a design flaw that has inaadequate cooling, when the fets gets shorted, it shorts the D1 and burn the R282 current sense resistor.
D1 is : https://ro.mouser.com/ProductDetail/863-MBRA140T3G Fets Q52 and Q51 are : https://ro.mouser.com/ProductDetail/595-CSD18543Q3A Current sense resistor R282 is: https://ro.mouser.com/ProductDetail/755-UCR18EVHFSR020
I suggest to change the Buck converter controller to wich is : https://ro.mouser.com/ProductDetail/595-LM5122MH-NOPB
After repairing this buck converter I sugest to mount a heatsink on the top of this two fets to prevent future fail. You cand glue the heatsink with termoconductive glue on top of the fets.
To repair the buck converter, you need to change the Q52, Q51, D1, R282 and I suggest to change the buck converter driver to (U16).
