Hp deskjet printer 6840 wont print .keeps on saying top cover is open when it is actually closed.

If you get this error:

Top Cover Open. The device cannot print because the top cover is open. Close the top cover and press continue, or cancel the printing.

then follow this guide:
HP Support document HP Support Center

1.Power off printer
2.Open cover
3.closs cover
4.swich on printer
ok

Please refer below for detailed troubleshooting of the specific condition:

PRINT CARTRIDGE light RESUME light POWER light Blinking Off On Problem

The printer top cover is open, or there may be something wrong with the print cartridge.

Solution

1. Close the printer top cover.
2. If the PRINT CARTRIDGE light continues to blink, continue with the following steps:
   1. Open the top cover. The print cartridge cradle will move and then stop.
   2. Locate the yellow arrow on the top of the print cartridge cradle. The yellow arrow points to a drawing of a cartridge that represents a symptom. Perform the task associated with that symptom.
   3. For a list of symptoms, refer to How to use the cartridge drawings under the top access door on a 900 series Deskjet .

this is the common problem of 5150 printer .you just open the top cover ,in your right hand you can see a black moving part it may not working properly. try to move back and forth many time ,then close and check your printer.

Hp printer properties best to do this with the usb attached. in the properties you will find printer name make model and setting go to settings and a list with links on depending on what windows you are using, there is auto shut down (2hr) etc on one of the drop lincs is standard and quiet mode. click to standers and save it should be out of that setting now. if still stuck use this link to fix problem with the printer. HP DeskJet 6520 6620 6840 6940 and 6980 Printers Top Cover Open Message...

hello,
To correct this problem, unlock the carriage from the printer‘s capping station.

1. Lift the lid to the printer (cartridges are on the right side.)
2. Turn the printer off, then power it on again.
3. Unplug the power cable from the back of the printer when the grinding noise starts.
4. Move the carriage towards the middle of the printer (this procedure may take a couple of tries to get the timing correct.)
5. Take out the cartridges and close the top cover.
6. Reconnect the power cord. The power and the resume lights (green and red) should be on.
7. Open the top cover, reinstall the cartridges, and close the top cover.
8. The printer should print the alignment page.
9. Print from another application.
   thank u

try to clean the copper contacts on the cartridge and printer with the help cotton moistened with water

Here's the answer:

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01065334&cc=us&lc=en&dlc=en&product=385458

The sensor is probably stuck, and it took me a few minutes to fix!!

Good luck...

Peter

I had the same problem, and the cause turned out to be the cover switch not being fully pushed in. On the underside right edge of the top cover, there's a little triangular protrusion that pushes down a black rectangular button (the cover switch) when the cover is closed. The problem occurs because the flimsy top cover is made of plastic and flexes slightly when you close it. This means that sometimes, the right edge of the cover won't seat properly even though it appears as if the cover is closed all the way. When this happens, the triangular protrusion isn't fully pressing the switch down.

To test if this is this is happening, send a print job to the printer and wait for the "top cover is open" error message to appear. Next, open the top cover door and locate the cover switch. It's a little black button in a rectangular hole at the right edge of the doorway near the ink cartridges. Take a pen or a car key and use it to push the cover switch down. You can also use your fingertip to do this if it's skinny enough. If you keep the cover switch pressed down, the power button should start blinking to indicate a print job is coming through. If the print job actually starts printing, then you know the problem was the cover switch.

In my case, all I had to do the fix the problem was close the cover and make sure it was fully seated by firmly pressing down the right edge of the cover until I heard a plasticky "click" noise. After that, the problem went away.

Hope this helps.

Hi,

I have that exact problem at work. There is a bump on the right side of the lid...and when you close the lid it presses on a lever. Check and see that the bump actually pushes that lever downwards. That's how the printer determines that it's closed.