Hi ,
If the printer stucks to the message "Warming up" during booting , I would suggest you to check by printing engine test page that will confirm if the printer engine is working fine except the formatter .
Use a pencil or bent paper clip to push the engine test button in.
Engine test switch is Located right side of the printer next to tray 1 shown below :
if engine test page comes fine , then Formatter and its component could be suspected . if the engine test page does not print , issue could be related to DC controller . It is Also observed that Formatter sometimes interrupts during Engine test page .Therefore Hp Technician can be consulted to test engine test page without formatter and diagonose further .
I work for Hp
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