HP LaserJet Problems and How to Fix Them

We've repaired HP LaserJets on 6th Road, Rawalpindi for over 25 years, and the same handful of problems come through the door every week. Most of them you can diagnose from the printed page, and several you can fix in five minutes without tools. Here's the list, from most to least common.

1. Prints are faded or light

• Faded everywhere, getting worse over days → toner running out. Remove the cartridge, rock it gently side to side 5–6 times, reinsert. You'll usually get a few hundred more pages; then replace or refill.
• Faded on one side only → toner is unevenly distributed (same fix), or the cartridge is seated slightly crooked. Re-seat it firmly.
• Faded but toner is new → check the driver isn't in EconoMode / 'toner save', and that print density isn't turned down. On some models the transfer roller is worn — a workshop job.
• Very light with a grey background → humid paper or a refilled cartridge with poor toner. Try a fresh ream.

2. Vertical lines or streaks down the page

• Thin sharp black line in the same place on every page → a scratch on the drum. The drum is inside the cartridge on most small HPs (85A, 78A, 05A, 26A, 59A), so a new or refurbished cartridge fixes it. On models with a separate drum (e.g. M227fdn's 32A) replace the drum.
• Wide grey or black band down one side → toner leaking inside the cartridge or a worn wiper blade. Replace/refill the cartridge; clean the inside of the printer with a dry lint-free cloth.
• White vertical streak (missing toner) → something on the laser window or a toner starvation track in the cartridge. Gently clean the laser/scanner window with a dry swab; rock the cartridge.

3. Ghosting — a faint copy of the image repeats lower on the page

Measure the distance between the image and its ghost. If it repeats every ~75–95 mm it's usually the drum (i.e. the cartridge on most models); if it's ~75–80 mm on a bigger machine or the ghost is smeared, it's the fuser. Humid or very thin paper makes ghosting worse. Try fresh paper and a known-good cartridge first; a fuser is a workshop replacement.

4. Toner smudges or rubs off the page

Toner that isn't bonded to the page means the fuser isn't getting hot enough — a worn fuser film or a failing heating element — or the paper is too heavy/glossy for the setting. Set the paper type correctly in the driver (e.g. 'Heavy' for card) and try plain 70–80 gsm paper. If plain paper still smudges, the fuser needs service. Don't keep printing: loose toner spreads through the machine.

5. Paper jams and mis-feeds

• Jams at the tray / printer doesn't pick paper → worn pickup roller (smooth and shiny instead of grippy). Wipe it with a slightly damp cloth as a temporary fix; replace it properly — it's a cheap part.
• Double-feeds → worn separation pad, or paper stuck together from humidity. Fan the stack before loading.
• Jams at the back / duplex unit → paper too heavy for duplex, or a bit of torn paper left inside. Open every door and check with a torch.
• Wrinkled / creased output → fuser rollers or paper guides set too tight. Set the guides to just touch the paper.

6. 'Toner low' or 'cartridge not recognised'

'Toner low' is just a warning — keep printing until quality drops. 'Not recognised', 'non-HP chip' or 'supply problem' after a refill means the cartridge chip has expired or isn't compatible with the printer's firmware. Chipped families (107A/106A/105A, 110A, 150A, 136A, 59A, 203A) need a proper replacement chip; our HP toner guide lists which cartridges are chipped. On some models you can acknowledge the message and continue; on newer firmware you can't — which is why we advise against firmware updates if you use compatible toner.

7. Blank pages or all-black pages

• Blank pages → sealing tape still in a new cartridge, an empty cartridge, or a failed laser unit. Check the tape first.
• Completely black page → a charging problem on the drum/cartridge or a faulty high-voltage supply. Swap in a known-good cartridge; if still black, it's a workshop job.

8. Printer is offline or won't print from the PC

Before anything else: power-cycle the printer, then the PC. Check the USB cable is in a rear port (not a hub), or for network printers that the IP hasn't changed (print a configuration page from the printer menu and compare). Reinstall the driver from HP's site if the printer shows as 'offline'. For Wi-Fi models, our HP Wi-Fi setup guide covers reconnecting.

When to bring it in

Fuser, transfer roller, laser unit, formatter board, gears and 'error 50 / 52 / 79'-type codes are workshop repairs. Our family workshop on 6th Road, Rawalpindi has serviced HP LaserJets for over 25 years — see our printer repair & toner refill service, or message us on WhatsApp with the model and a photo of the problem page and we'll tell you honestly whether it's worth fixing. And if you bought the printer from us, it's covered by the 3-month service warranty.