HP LaserJet 4

How to Identify and Fix Common Problems ?

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For cleaning, HP recommends using HP Equipment Cleaning Wipes, but you can use an HP-approved lint-free wipe and deionized or distilled water. Note: If dark spots appear on back side of prints, clean drum screen. Note: If minilab prints more than 2000 prints each day, clean drum screen up to twice daily.
Do not touch the surface of the drum unit. 5. Clean the roller by gently wiping the entire surface with an alcohol swab, such as a medical pad or wipe, or cotton swab lightly moistened with isopropyl alcohol (91% is best, but 70 – 75% can use used).
Water will often get the job done and it has the least risk factor involved when it comes to cleaning your drums. Using a damp cloth to wipe down your kit will get the job done most of the time. If you want to do some heavier cleaning, you can use dish soap.
Step Three: Cleaning

After you have removed the chunks of toner, dip a cotton swab in rubbing alcohol. Carefully wipe off any dirty areas visible on the drum. If the drum unit is dirty, apply some rubbing alcohol onto your lint-free cloth and carefully wipe the body of the drum unit.

What is the drum unit? The drum unit transfers the toner to the paper. The laser printer puts the toner on the roller called “The photosensitive drum” inside the drum unit, and then prints letters and images by fixing toner to the paper by heat and pressure.
Just like computers, printers have volatile memory (RAM) that is removed when you turn the printer off. Volatile memory requires power to store the information. Deleting volatile memory is easy: Simply shut down or unplug your printer for a minute or so.
Use isopropyl alcohol or ethanol according to the manufacturer`s safety guidelines, as applicable. Wipe the roller with a lint-free cloth dipped in isopropyl alcohol or ethanol. After cleaning the roller, make sure that no lint or other material remains on the roller.
Why is it important to clean a laser printer? Printing is vital to all businesses so ensuring your laser printer is thoroughly cleaned is crucial as it allows your machine to continue working efficiently. Cleaning a laser printer is easy with the correct equipment, however they are prone to dust and debris.
The most obvious is most common on laser color printers and can be detected by a flashing message on the printer display screen. Other signs of a bad printer drum include printing blank pages, printing gray pages and strange sounds coming from the printer as it prints.
The most obvious is most common on laser color printers and can be detected by a flashing message on the printer display screen. Other signs of a bad printer drum include printing blank pages, printing gray pages and strange sounds coming from the printer as it prints.
Step Three: Cleaning

After you have removed the chunks of toner, dip a cotton swab in rubbing alcohol. Carefully wipe off any dirty areas visible on the drum. If the drum unit is dirty, apply some rubbing alcohol onto your lint-free cloth and carefully wipe the body of the drum unit.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Expired Ink Cartridges – Any way to move paper with old cartridges?
ANSWER : You could try disconnecting the printer from the computer. Then change the date on the panel to prior to the expiration date. That should fool it.

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HP LaserJet 4

Dell 3100cn drum cartridge replacement
ANSWER : I have the same problem with excess toner causing lines over the printed page. Have tried to find where the excess toner is stored but cannot do so. No green arrows; there are blue errors but there are no screws beneath these. Have tried removing adjacent screws, but this did not help. Does anyone have a picture of the actual site where the screws need to be removed; for the Dell 3010cn drum cartridge? Bernie

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HP LaserJet 4

no color cart. new & clean
ANSWER : yes

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HP LaserJet 4

Epson, sudden cannot recognise cartridges error
ANSWER : Hi, I have exactly the same problem than you, I’ve been trying to solve it since 6 months. I have an Artisan PX730 WD, and the genuine cartridge can’t be recognized all together. And status monitor indicates same thing than you.

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HP LaserJet 4

run with empty ink cartridge
ANSWER : The only way is to buy a chip resetter and reset the chip on the cartridge. You can find them online for about $5. You just hold it against the cartridge until the light turns green. You do run the risk of damaging the printhead due to overheating because of no ink in it.

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HP LaserJet 4

Chatter from toner cartridges before printing
ANSWER : The video may have the answer you want

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HP LaserJet 4

Color LaserJet 2500 new drum doesn't work.
ANSWER : The drums have a chip on them and it should have reset when you installed it. If not, then read this thread.

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HP LaserJet 4

PGBK cartridge not working
ANSWER : Did you try removing the print heads and flushing them under hot tap water?

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HP LaserJet 4