Complete cleanup of the HP PSC2100 series printer scanners

If scanning with your PSC21xx produces pictures of low quality, vertical streaks and/or strange color lines, follow this guide.

Material needed:
1. Distilled water or one of the glass cleaner mentioned in this HP document.
2. Lint free cloth(Eg. Coffee filter)
3. Cotton swabs(In the original box)
4. Small flat tip pliers
5. Pure H20 / Distilled water
6. Clean glass for the water
7. Microwave
8. A plate
9. Kitchen/Asbestos glove
10. Torx T-10 tip screwdriver
11. Flat tip screwdriver
12. Cheap BIC-style pen
13. Some time

How to solve:
1. Power the printer off, disconnect USB and power cables
2. Bring the printer on a clean surface where you will be able to work.
3. Put away the scanner cover.
4. Take your flat-tipped screw driver and lift off the control panel face plate you installed when you got the printer out of the box.
Removing control panel face plate
5. Once the plate is removed, use the ink tube of your cheap pen, push it in the square hole under the grey and green scan buttons, and pull the panel like in the next picture.
Removing the control panel
6. Put the control panel away by pulling off the connector. Always use the blue part to push and pull the connector, it is really fragile.
Removing the panel connector
7. Next, use a Torx T-10 tipped screwdriver to remove the 3 screws.
Torx T-10 tip and screw position
8. Now, you should be able to lift every corners that had a screw. To lift off the other, you will need to push in the front-middle while pulling the loose front corner up like in the picture.
Pulling off the last corner
9. You still can't remove the cover completely tho. You will need to, by using the back corners, to pull while swinging the back corners wihout excessive force and it will come off.
10. Put the scanner glass assy away.
11. You now need to pull out the scanner assy. Start by pushing slowly the assy in the middle. The motor sound is normal. Then, unplug the connector using pliers(Using the blue rectangle), and then, pull off the folded wire part by pushing to the left and pulling the wire.
Scanner connector + it's tape
12. Now, you're going to pull out the scanner assy. the danger here is that you might break the belt if you just pull it out without disengaging it. Insert a cotton swab(remove the cotton) where the belt is hidden under the plastic to get it out. Then, use some pliers to pull out the other side. It takes some patience to do this.
Where to put that Q-Tip
13. Simple step, pull the assy. from the shaft and put the rest of the printer away. You're going to work on the scanner assy. from now.
14. Insert a flat-tipped screwdriver to push the tabs on each sides of the assy. pull at the same time.

15. You've opened the scanner assy. Simple, no? You can see that there is not 1 but 4 mirrors finally. Now, put a glass of distilled water in the microwave for 2 minutes(1300w), pull it out with a kitchen glove and put it on a plate. Now, put a new out-of-the-original-box cotton swab in the HOT water and clean the 4 mirrors with it. Dry them before the air does with dry swabs. If some water remains, use an other dry swab.
Mirror 1Mirror 2, 3 and 4
16. Rebuild the printer: Do the opposite instructions, but stop before you put the scanner glass. First, re-heat the water and clean the glass with the same hot water using coffee filters this time. If there were some kind of lines on the glass that gave strange colors while scanning, you might want to remove them. Apply some more pressure and wipe them until they disappear. Use an other coffee filter to dry the thing up.
17. Completely rebuild the printer.

Credits to people at forum to have found how to remove the control panel. The only new thing I had to find was how to remove, open and clean the scanner part.