HP Error Er-04: Paper jam in input tray
Also shows as: Er/04, Er 04
✅ Usually fixable yourself
Paper is jammed in the input tray.
What to try
- Clear the jammed paper from the input tray area.
When it needs a technician
HP's table does not call for service for this code.
Which models show Er-04
HP documents this code for models including HP LaserJet Pro MFP M28-M31 series.
First steps for any printer error
- Write down the exact code before you do anything else — similar-looking codes often mean completely different things.
- Power the printer off, unplug it for a couple of minutes, then power it back on. A surprising number of transient errors clear here.
- Open the covers and check for paper scraps, packaging material, or anything blocking the carriage.
- Check the cartridges or tanks are genuine, correctly seated, and not empty.
- Confirm the printer is plugged directly into a wall outlet, not a power strip or extension lead.
- Check your model’s own manual — codes are model-specific, and the manual is the authority for your machine.
Source: HP Customer Support - HP LaserJet Pro MFP M28-M31, Interpret control-panel light patterns. Codes are model-specific, so your own model's manual is the final word. Reviewed October 2026.
Still showing Er-04?
Tell our printer technician your model and what you've tried. You'll find out whether it's fixable at home or worth repairing at all.
Ask about my printer — $1Eric Paul Amora · Printer & Hardware Repair Technician
Related HP codes
Er-01 — Input tray emptyEr-02 — Door openEr-03 — Paper pick failureEr-05 — Paper jam in toner cartridge areaEr-06 — Paper jam in output binEr-07 — Toner cartridge missingEr-08 — Toner very low, set to stopEr-11 — Toner cartridge issueEr-14 — Toner cartridge protectedEr-17 — Unauthorized toner cartridgeEr-30 — Flatbed scanner errorEr-50 — Print engine error