Also applies to: HP LaserJet 4000, HP LaserJet 4000n, HP LaserJet 4000se, HP LaserJet 4000t, HP LaserJet 4000tn, HP LaserJet 4050, HP LaserJet 4050n, HP LaserJet 4050se, HP LaserJet 4050t, HP LaserJet 4050tn
For HP LaserJet 4000 and LaserJet 4050 series printers, Hewlett Packard recommends the installation of a maintenance kit after every 200,000 pages printed. While this is a good recommendation, the time to install a new maintenance kit will vary depending on printing conditions. For example, if the printer is in a dusty environment, if paper is used that produces higher then normal levels of paper dust, or if low-quality aftermarket components are used, the estimated pages may drop significantly.
Loosen the two fuser assembly screws shown in the image and slide the fuser straight out.
To install the replacement fuser, align the left side, then slide the fuser into the printer until fully seated and tighten the two screws. Replace the rear output tray and duplexer covers (or duplexing unit, if you removed one).
Looking at the front of the printer, open the top cover and remove the toner cartridge. Use the hook end of the blue transfer roller removal tool provided in the kit to hook under and carefully lift the left and right ends of the transfer roller up out of the retaining clips. Remove the transfer roller from the printer.
Please note: When handling the replacement transfer roller, do not touch the black roller surface. Oil from your skin can adversely affect print quality. Handle the transfer roller by the ends, or use latex gloves to keep the surface clean.
On the gear end of the replacement transfer roller, there is a black plastic collar. Rotate this collar so the open end faces down, then install the new transfer roller into the printer with the gear toward the left. Press down on the roller until both ends snap into the clips.
Installing the tray 1 (multi-purpose tray) pick-up roller
With the toner cartridge out of the printer, open tray 1 (the multi-purpose tray). Remove the plastic cover above the roller, marked by a number 4 in many models, by pulling straight out (see picture below).
Next, gently pry downward on the blue tab on the pick-up roller using a flat-blade screwdriver to release the pick-up roller, then lift the roller straight up off of the shaft and remove it from the printer.
Installing the feed rollers in paper cassette bays
Note: The feed rollers and separation rollers on a LaserJet 4000 or a LaserJet 4050 series printer are identical. Each lower tray uses one feed roller and one separation roller. If you have one lower tray, you will only use two rollers. Printer models that end in “T” (4000T or 4050T) came with a built-in additional tray. These models or models with an optional add-on paper cassette will use four rollers. A 4000T or 4050T that also has an optional add-on lower cassette will use all six of the rollers provided in the kit.
Remove the paper tray(s) from the printer and place near the edge of the work surface to allow easy access to the underside of the paper tray bay. Remove the feed roller by pinching the blue lock tab on the roller, then sliding the roller off the left end of the shaft. Slide the replacement roller in place and repeat the process for each additional cassette bay, if equipped.
Installing the separation rollers in paper cassettes
With the paper cassette out of the printer, remove the paper tray access panel by pressing the release tab (circled below) toward the back end of the tray, then swing the panel upward. Remove the separation roller by pinching the blue lock tab and sliding the roller off the end of the shaft. Slide the replacement roller in place and repeat the process for each additional cassette, if equipped.
After the expected life of the maintenance kit items, the printer will display a message recommending printer maintenance. After installing the maintenance kit parts, you will need to reset the counter to turn off the reminder. To reset the counter, power on the printer while holding down the left side (minus side) of the “Item” button and the left side of the “Value” button. After “RESET MAINTENANCE COUNTER” is displayed, release both buttons.
NOTE: Some formatter board versions do not recognize the above steps to reset the counter. On these printers, the maintenance counter must be reset through the service mode.