But it doesn’t. There is no paper stuck in there.
Still, the screen keeps flashing “paper jam”, and I can’t get it to print. I’ve tried turning it off, I’ve tried pressing cancel, but it’s stuck in “jam mode”.
Any thoughts on how I can fix this? It’s a HP Officejet J6840 Printer.
Check the paper path for a scrap of paper stuck in a sensor.
You know this is what we all thought of. The action starts at about 1:10 of the video.
Mine does this all the time and I always have to restart my computer (assuming your computer is connected to the printer).
I’m seeing any images for the printer you mentioned, but if it’s the type of printer where you load the tray with paper at the bottom and it comes out the top then there’s probably an access panel on the back. Remove the panel and make sure there isn’t a piece of paper jammed in it.
Well, I just did restart my computer for another reason before I read this, so let’s see if it worked… Nope!
Yes, it has one. I did take it off, and inspected it. No paper.
There’s probably a tiny speck of paper in there somewhere - just enough to confuse an optical sensor.
If you have “canned air” dusting spray, take off all trays and access panels and blast away at the insides of the printer from every opening. Let it sit for a few minutes - chances are good that some of the liquid spray got inside and it simply needs to evaporate. Then, cross you fingers and hope the printer works. If not, you may be dealing with a failed sensor, at which point, it may be quicker and cheaper to get a new printer. “Home-grade” printers just aren’t very durable any more. 
Yeah, that’s what I was thinking of trying next. I can’t imagine it would be worth it to pay someone to fix the damn thing. Thanks.
Have you tried smacking it?
:smack:
That’s what I said 18 minutes after you posted.
Just have a good blow into anything you find along the sides of the paper path.
I was talking about going to the hardware store to buy some “canned air”.
Thanks. I didn’t mention it, but that is one of the things I already did before posting the OP. I don’t think that is as good as using the “canned air”, though, which is why I’m planning to run over to the hardware store in a few minutes.
There are all sorts of ways of ‘having a good blow’.
Good luck.
OK, so I opened a can of whoop-ass on the innards, and it still thinks there is a paper jam.
So, let me reword the OP: Is there a way to override this error message? I keep thinking that if I can just feed some paper through the damn thing, it’ll clear up whatever sensor malfunction is going on.
Open and close all the “doors” and make sure that they are closed. My HP 3300 is kind of fussy that way.
Can you do an offline printer test?
There are 2 types of paper sensors, one is a spring loaded micro switch and the other is an optical sensor. You can have a piece of paper jamming the micro switch or dirt on an optical sensor. You need to look at the path the paper takes and look for the switches.
I used to work for HP fixing Officejet printers. Granted, it was years ago, but HP isn’t known for radical design changes year to year so their printers are still pretty much the same as when I worked there. I couldn’t find a model “J6840” on the HP website, but I did find “J6480”. Here is the doc on how to clear a paperjam. It also has directions on cleaning the paper pick rollers and the duplexer (if you have one). The document for out of paper message might be helpful, and here’s how to do a partial reset. Did you also check where the cartridge carriage assembly parks? If there’s paper under there it can cause a paperjam message too.
The partial reset might clear the message, but if it’s a malfunctioning or stuck sensor, forcing paper to go through it won’t fix it. All it’ll do is piss off your printer, then you have a rogue printer on your hands. Not pretty.
My Dell has been doing that too. Of course, Dell sucks.