HP LaserJet 3330 “scanner warming up” Error

January 20, 2010 by
Filed under: Uncategorized 

Do you have a Laserjet 3300 series or 3380 series laser printer with the “scanner bulb warming up” error? This is caused by a dirty scanner glass and or dirty scanner mirrors. The scanner lights the bulb and waits for it to get to a preset brightness level. When the glass or mirrors are dirty the machine thinks the bulb is not getting bright enough so it waits for it to warm up. We have used the following instructions to repair many of these units in our service shop. Because of the technical skills required these instructions are provided to use as-is, we accept no responsibility if you damage your printer.

HP LaserJet 3330 Scanner Unit Disassembly Procedure

This is not an Hewlett Packard document, the author does not work for Hewlett Packard and is not responsible for any damage you do to your printer. This procedure is for skilled repair technicians and is not recommended without some knowledge of equipment repair. Proceed at your own risk.

1. Open the document feeder and pull up on the two black tabs on the left and right.

2. Pull up on the right part of the doc feeder then the left, remove doc feeder, set aside.

3. Open front door and rear fuser door.

4. Remove screws closest to teal colored fuser release levers. (side cover screws)
5. Pull right cover out from back while releasing clip on bottom of cover, pull cover towards the back and remove.
6. Push on indentation at back of left cover and pull out at back, this cover is hinged.
7. Remove four screws now visible at base of scanner assy., two on left two on right.
8. Slide covers towards back and remove.
9. Remove two screws in the back just above the fuser and just below the scanner assy. base.
10. Remove two screws in the front, visible now after removing the scanner assy. base covers on the right and left (the left one is just behind the hinged cover near the top hinge.)
11. Remove flat ribbon cable (on left side) at either connection point to disconnect scanner assy. from print engine.
12. Entire scanner assembly can now be slid forward and removed.
13. Close the front, rear and left side doors on the print engine portion and set it aside.
14. Grab front panel face plate at top and pull forward and remove. (or pry gently at top of face plate).
15. At top of exposed front panel you will see four slots in the scanner assy. Near the third one from the left there is a latch (dark grey plastic). Push down on the latch with a screwdriver and slide the whole panel assy. to the right. Lift up and out making sure to disconnect the cable.
16. Remove the three screws in the now exposed dark grey front panel cradle and cover, remove the two cables connecting the cover to the main board, pry gently at the top outer corners of the cover and pull it forward and down, remove the cover.
17. Now remove the four scanner assy. screws (one and the center front, center back, center right, center left) all are facing down under the assy. (Or just flip it upside down and remove the four visible screws.
18. Turn the unit back upright and remove the four screws at the back/top (two of them are down inside where the doc feeder normally goes.)
19. Remove the top scanner cover.
20. DANGER your about to work on the scanner carriage itself there is a really good chance that you could break it or the mirrors or bulb so proceed at your own risk.
21. At the top and bottom left side of the black cover enclosing the mirrors are two slots, if you put a small screwdriver in the slots and push gently to the right and lift that side of the cover it should come loose. Then open it to the right and remove it from the right slots.
22. Remove the black screw at the front of the assy., Disconnect the white wires from the CCD board and out of the harness, lift the clear plastic bulb holder out with the bulb then remove it from the rear. (it’s a tight fit at the front.)
23. The top mirror is held in by some really tight clips they have to be removed from the bottom right (clean the mirrors without this step if possible). NOTE: optical mirrors are not like a bathroom mirror, there is no glass covering the reflective surface. The back side of the mirror has glass covering it so if you get it in backwards it won’t work. (The way to tell which side you have is touch your screwdriver to the mirror and if it’s the right side the screwdriver will appear to touch the reflection of the screwdriver, if it’s the wrong side the screwdriver will not touch the reflection of the screwdriver because of the glass covering the reflective surface.
24. Now clean the remaining mirrors and lens very thoroughly with alcohol. Make sure they are very clean. You can put the top mirror back and clean it in place to make cleaning it easier.
25. When re-assembling the top cover check to make sure the white strip on the right side is clean.
26. Reverse procedure for re-assembly.

We also have the full service manual available here: Service manual

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One Comment on HP LaserJet 3330 “scanner warming up” Error

  1. Randal on Thu, 15th Nov 2018 8:11 am
  2. Before all this hoo-ha regarding the Yr of the Seasoned a
    year ago, there clearly was another year when the pro confirmed
    the things they’re made from.

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