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Robert M.
Robert M., Consultant
Category: Printers
Satisfied Customers: 9110
Experience:  30+ yrs. experience in NYC computer industry working with PC and networks, banks, brokerage, legal etc.
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I have a hp office jet pro L7780 all in one. I can print

Customer Question

I have a hp office jet pro L7780 all in one. I can print from my laptop etch but when I go to copy or scan it comes out pitch black what can I do to fix this thank you Marcia
Submitted: 11 months ago.
Category: Printers
Expert:  BobJamIT replied 11 months ago.

Does it only happen when using the glass? What happens when you use the automatic feeder, does it work fine then?

Customer: replied 11 months ago.
Just when I am using the glass
Expert:  BobJamIT replied 11 months ago.

Please try this also:

Reset the printer, this can force some types of scanners to calibrate which might fix the problem.

  1. Remove any items from the scanner glass and ADF, then close the scanner lid.

  2. With the printer turned on, disconnect the power cord from the printer and from the wall outlet or power strip.

  3. Wait at least 15 seconds.

  4. Plug the power cord back into a wall outlet.

    Note: HP recommends connecting the printer power cord directly to a wall outlet.

  5. Reconnect the power cord to the printer.

  6. Try to scan, copy, or fax.

    Please let me know if it works after performing a "Reset".

Customer: replied 11 months ago.
When I copy it is just black and using up my black toner
Expert:  BobJamIT replied 11 months ago.

Even after doing a "Reset"?

If so, then a good cleaning is likely in order:

Clean the scan glass and underside of the scan lid with a soft, lint-free cloth sprayed with glass cleaner.

  1. Turn the printer off, then disconnect the power cord.

  2. Lift the scanner lid.

  3. Spray a soft, lint-free cloth with glass cleaner, then wipe the scanner glass, glass strip (if present), the white backing under the scanner lid, and the white strip under the lid (if present) until clean, dry, and streak-free.


    To protect the interior printer parts, do not spray the cleaner directly on the glass or on the underside of the lid.

    Figure : Clean the scanner glass and under the lid, and any glass or white strips (if present)

    1. White scanner lid backing

    2. White ADF scanner lid strip (if present)

    3. Glass ADF scanner strip (if present)

    4. Main scanner glass

  4. Reconnect the power cord, turn on the printer, close the scanner lid completely, then scan, copy, or fax.

Customer: replied 11 months ago.
Still black
Expert:  BobJamIT replied 11 months ago.

Hi Marcia,

Did it ever work?

What is the history of this printer, was it purchased "used"?

Does the light come on when scanning?



Customer: replied 11 months ago.
It was purchased new and the light cones on when copying and scanning
Expert:  BobJamIT replied 11 months ago.

When was it purchased?

Did it ever work?

Customer: replied 11 months ago.
about 4 yrs ago have scanned one page about 17 times a year.
Expert:  BobJamIT replied 11 months ago.

Hello Marcia,

As these suggestions have not resolved the issue, I must opt out of this transaction. Maybe another technician can offer some advice that will help.
Thank you,

Expert:  Robert M. replied 11 months ago.

your problem is the scanner is broken.

Most likely the light that it uses to do the scanning has burnt out.

that is a pretty common problem with scanners that are a few years old.

On very high end scanners the bulb can be replaced.

On home printers its really not worth the bother. You have to take the entire thing apart and probably heat melt the glue around the glass and then glue it back together after and hope you didnt lose the calibration.

Its just cheaper and easier to buy another printer.

Sorry it is not better news but at least you know what happened and you won't waste a lot of time trying to fix it.