Horizon Forbidden West: Death's Door Bunker Red Door Code
There are a handful of codes you'll come across as you venture through the world of Horizon Forbidden West. The first code you'll likely encounter, unless you've been delving into the various ruins in The Daunt or the lands beyond, is for a locked red door. This shows up while you're in the bunker during the Death's Door story quest.
After you use the power core in the facility for the first time, you'll need to eventually move a crate out of the way to continue forward. Afterward, you'll need to activate a Firegleam with the Igniter to retrieve the power core and use it again.
Soon, you'll do some (pesky) platforming across the facility's flooded area; be sure to explore this area since it's filled with loot. Eventually, you'll activate yet another Firegleam and enter a hazy, purple-lit room with a desk in the middle.
This is where the red door is located (note, I've already unlocked it in the screenshot below). To open the red bunker door, you'll need to input a code in the terminal just left of it.
If you want to find the red door code yourself, head into the room opposite the door. Enter, and turn left to find a datapoint. Scan the data point, and open your Notebook. Scroll to Text Datapoints and select the entry called Bad Urges. Read it for the code.
If you'd rather just know what it is and not worry about the datapoint at all, the red door code in Death's Door is 7482. Punch it in to the terminal and continue on with the mission to retrieve GAIA's backup.
That's it! Now that you have the red door code, you're almost at the access console and what you're after. Death's Door is almost complete. For more Horizon Forbidden West guides, head over here.