HP 2840 Jam in print paper path, Open door to clear.

[SERocks]

Hi,
I have a customer with a 14 month old HP 2840. Running great till today. It was giving her a "Jam in print paper path, Open door to clear." Error. She opened the printer and removed 2 sheets of paper carefully from the front and back and closed the doors and still gets the error. She called me in to check out the problem. I examined the paper she removed, both intact and undamaged. I walked through all the areas of the printer, removing the fuser, the tray, drum unit, and the one toner that could be removed. Looked through the entire machine with a flashlight and could see nothing. The only place it might be is up behind the carousel toner cartridge unit. Does this happen on this unit?
One thing is you can not rotate the unit. It will say in the display rotating to magenta but the unit does not spin. Is there a way to manually rotate the carousel? As it is right now it is either locked or jammed so I do not want to force it. Is there a place I can see a diagram if I am going to need to disassemble it? Thank for your help.

[Rawko]

Recognize the grill underneath the blue carousel rotation button.With a flat-head screwdriver, a key or similar device, press the grill locks toward the center of the grill and lift it out.Remove the toner collection tray. Depending on weather the printer has had a PEP kit installed access to the tray will look different. With the PEP kit tray just pull it out of the printer.Remove any obstructions in the toner collection chambers.Verify that the carousel moves correctly.If the carousel does not move, lift up the carousel release lever located at the very back of the print cartridge chamber.Rotate the carousel until a print cartridge is in a position to be removed.Rotate the cartridge’s blue lever to the right and pull out the print cartridge.Hope this will help you..