How to Troubleshoot an HP LaserJet 4 and a 2001A
- 1). Open the top cover of the LaserJet 4 and remove the toner cartridge. Vacuum the interior of the printer with a small vacuum cleaner like the kind used to clean computer components.
- 2). Wipe the interior of the printer with a soft cloth to remove any remaining toner residue and paper dust. Continue cleaning the printer until no more residue comes off.
- 3). Pull out each of the paper trays and adjust the paper guides so that they sit flush against the paper. You will have paper jams if the paper guides are too tight or too loose.
- 4). Fill each paper tray to only three-quarters full. If the paper trays are too full the LaserJet 4 tends to grab more than one sheet of paper at a time, resulting in frequent paper jams.
- 5). Open the left-hand door on the LaserJet 4 and locate the fuser cartridge. The fuser has a yellow message indicating that the unit is hot. Turn the roller on the outside of the fuser cartridge and remove any jammed paper. Replace the fuser cartridge if the roller does not move freely.
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