I will show you how to replace the door sensor and the LED screen for the HP OfficeJet Pro 8000 series, such as 8010, 8018, 8020 8022, 8025, 8028, 8035. If you get this error, the first thing to check is the front panel and see if the nipple is still there. Here it is. It looks okay, and if it clicks. If it does, then you've got a bigger problem. It's probably the sensor malfunction. Stick something thick into that hole. If it still says the doors are not closed, you'll probably need a new sensor like this. There's nothing magic about a nipple. You can have a piece of thick plastic and stuck it between them, and the printer will think the door's closed. Remove it, and the door's open.
If it's not detecting that piece of plastic, the board may need to be replaced. Where do you go to find a new board? Go to bchtechnologies.com and go to printer parts, HP electronic board, and assembling. Here's the door cover. The same thing if you have a cracked screen or your screen is not responding. I'm also going to cover the installation of LCD here. All that doesn't mean that you need a new LCD, okay? You'll need both a T10 and a T6 screwdriver. If you don't have one, I'm going to put a link above. That's a must-have if you have HP.
Remove the screws from the top. Count it; make sure it's eight. This printer hinge can be removed by just simply pushing it forward. Now the scanner can be pulled up to 90 degrees and expose some screws underneath. Currently, there are four screws to be removed. Now the panel can be peeled off both sides, but let me show you this for the hinges. Please pay attention to where the hinges are, so next time we install, you'll install this way. You don't have to uninstall this, but I know 99% chance it's going to fall out, and you'll be like, "Oh, how do I put it back?"
Okay, left side, there are two cables. The smaller cable is for the door sensor, and the bigger cable is for the LCD panel. Now we're going to disconnect both cables, and the whole top cover can be removed. We're going to take this piece off. See this cover and trace it down, see where the base is, and here's the bottom. Use your finger now to lift it a little bit, and now use the screwdriver to push down the tap from here and here.
Now the board is exposed. Take out the T6 screwdriver bit that you bought from bchtechnologies.com. We need to remove the LCD. On the front, this tab, bend that inside, and the LCD can be opened. Now we're going to free all the cables. Let me show you the hinge is a half-circle. You rotate the hinges to where the half-circle is and pull it out. The installation reverses what we did.