You must remove the air duct before removing or installing the following components:
Power distribution board
Power supply backplane (Sun SPARC Enterprise T5240)
Fan module boards
Hard drive cage
Hard drive backplane
Caution - To prevent the system from overheating, ensure that the air duct is correctly installed before powering on the server.
Disengage the rear of the air duct from the motherboard and rotate the air duct forward.