For dead space on the xbox 360 a gamefaqs q a question titled okay how do you unlock the locked doors lockers and bins.
Opening locked doors in dead space.
Each time you visit that level you will need to expend a power node to open that.
You simply need a straight stiff.
Insert the pick above the wrench.
Same goes for any other door in the game.
Inside is a small button that needs to be pushed to unlock the door.
You return to this area later in the game.
As previously noted this skill takes a lot of practice to master so have plenty of cheap practice locks on hand if you hope to get good at it.
Node locked doors are doors that require a power node to open.
Use the leg of the pick to find and push each pin up and out of the tumbler.
If it is locked at first you eventually return and it will be unlocked.
But get ready to blast your first real enemy remember target the limbs you may also.
Once all pins have been moved the lock should open.
Dead space 2 wiki guide.