A question about Quake 4, single player for the PC...?

I am having problems trying to get through a door in the "Hanger Perimeter" section, still early part of the game. After you meet up with the rest of your squad you go to an open courtyard section with machines going around and around and crates lying around. You go up a few stairs and there is a door. From reading the walthroughs I should be able to go through this door. I cannot. It is locked but there is a panel next to the door. Can anyone tell me how I get though this section. Thanks