I can't find the code to the door in the room with the brain scorcher in the red forest section. There are two doors in the lab requiring access codes. I got the codes for the first door you find off of a dead soldier, it was all ammo and etc. But I can't find info on opening the other door anywhere. It's not even mentioned in the ign or gamespot guides, as if the authors didn't even look around the room and see the door. I'm really curious as to whats on the other side. Someone please, if you have the access code, post it!
I can't help you as to where to find it but one thing I did learn is that you can not use codes that you have not "found". In the Lab X18 level I found a code and then got stuck and quit and came back later. I had forgotten to save my game so had to start from before I "found" the code. But I still remembered what is was (1243) and tried to just skip to the door since I had already done it. But even though I entered the right code it wouldn't open because the game knew I had not gone to the body and got the code. So it does not let you cheat / cut corners like that.