scan unit open or exit jam

[Inesmurray]

Our HP Color Laser MFP 178 179 keeps showing "scan unit open or exit jam", although we have a clear paper path and the scan lid seems well closed. On the app the it says the toner cartridges are missing, although we have checked they are seated properly.

[Nal_NR]

Hi @Inesmurray ,

Welcome to the HP Support Community. 

I'd be glad to help you! 

I understand that you are having issues with the scan unit open or exit jam", error.

For your HP Color Laser MFP 178/179 printer showing "scan unit open or exit jam" errors and indicating missing toner cartridges, let's go through some sensory-based troubleshooting steps to help you resolve these issues. We'll focus on a tactile and visual approach, allowing you to carefully check each component.

Visual Inspection of the Scanner Lid:

• Look and Feel: Gently open and close the scanner lid. Ensure it sits flush against the printer when closed.
• Check Hinges and Latches: Feel along the hinges and the edges to ensure there are no obstructions or broken parts preventing a secure close.
• Light Test: Close the scanner lid and see if any light is visible through the edges, indicating it’s not fully closed.

Check for Paper Jams:

• Listen: Open the front, back, and top covers of the printer. Pull out any trays and gently slide your fingers along the paper path, feeling for any bits of paper or obstructions.
• Look Closely: Shine a flashlight through the paper path, including the exit and feed rollers, to ensure there are no hidden pieces of paper.

Inspect the Scan Unit Sensor:

• Touch: Inside the printer, near the scanner lid hinges, locate the scan unit sensor or small plastic tab that triggers the "closed" signal.
• Feel for Movement: Gently press and release the sensor or tab to ensure it moves freely and isn't stuck or broken.

Visual Inspection of the Scanner Lid:

• Look and Feel: Gently open and close the scanner lid. Ensure it sits flush against the printer when closed.
• Check Hinges and Latches: Feel along the hinges and the edges to ensure there are no obstructions or broken parts preventing a secure close.
• Light Test: Close the scanner lid and see if any light is visible through the edges, indicating it’s not fully closed.

Check for Paper Jams:

• Listen: Open the front, back, and top covers of the printer. Pull out any trays and gently slide your fingers along the paper path, feeling for any bits of paper or obstructions.
• Look Closely: Shine a flashlight through the paper path, including the exit and feed rollers, to ensure there are no hidden pieces of paper.

Inspect the Scan Unit Sensor:

• Touch: Inside the printer, near the scanner lid hinges, locate the scan unit sensor or small plastic tab that triggers the "closed" signal.
• Feel for Movement: Gently press and release the sensor or tab to ensure it moves freely and isn't stuck or broken.

Please find the remaining steps in the next post.

Please mark this post as “Accepted Solution” if the issue is resolved and if you feel this reply was helpful click “Yes”.

[Nal_NR]

Hi @Inesmurray,

Please find the remaining steps below.

For "Toner Cartridges Missing" Error

Check Toner Cartridge Seating:

• Feel for Secure Placement: Open the toner access door and firmly press each toner cartridge into place, ensuring you feel it click or lock into position.
• Visual Check: Look for any misalignment or gaps around the toner cartridges that could indicate improper seating.

Examine Toner Cartridge Contacts:

• Touch Contacts: Carefully remove each toner cartridge and feel the metal contacts or chips on both the cartridge and printer. Clean them gently with a dry, lint-free cloth.
• Visual Check: Look for any debris, dust, or toner particles around the contacts that could affect communication.

Reset Toner Cartridges:

• Remove and Reinsert: Remove all toner cartridges, wait for a few seconds, and then reinsert them one by one, pressing firmly into place.

Printer Cover and Sensor Check:

• Close Sensory Check: Ensure all printer covers are properly closed by pressing each one until you feel them securely click into place.
• Listen for Confirmation: When closing the toner access door, listen for the clicking sound that indicates it is fully closed.

Other steps:

Power Cycle the Printer:

• Power Off and On: Turn off the printer, wait for about 30 seconds, and then turn it back on. Listen for the usual startup sounds and check if the errors persist.

Firmware Update:

• Visual Guide: If accessible, update the printer firmware through the HP Smart app or HP's website to ensure all software is up to date.

Check for Physical Damage:

• Touch and Visual Check: Run your fingers along all edges and components inside the printer to check for any broken parts or unusual movements.

If these steps do not resolve the issue, the sensors or internal components might be damaged and could require servicing.

In such cases, I would recommend you contact phone support.

Hope this helps! Keep me posted for further assistance

Please mark this post as “Accepted Solution” if the issue is resolved and if you feel this reply was helpful click “Yes”.