Update: In case anyone else has this issue. What I thought was going to be a major problem turned out just to be replacing the hot end assembly…
My go-to 2 year old Ender-3 V3 CoreXZ decided to finally show an error I can’t figure out. It’s a simple Key:2564 “Nozzle not heating” but the bed stopped heating at the same time in the middle of a print. Up to this point it’s been working flawlessly. Of course it’s out of warranty but I’ll write @Creality anyways for suggestions. 
Board# CR4CU220812S12
Checked and tried a known good thermister still the same error.
Opened the bottom and checked for loose wires, burns, fuses but not sure what else to look for.
I haven’t been able to find a motherboard yet but I might have to order one… 
Anyone have ideas what’s wrong…?
I searched the forums and couldn’t find anything that might help. Has anyone had this issue with both the bed and the nozzle stop heating
Thanks for any help… 