Print cartridge faulty or incompatible Desk Jet 6840

[fmd3]

MacBook Pro. I recently installed Lion (10.7.2). All the drivers are up to date.

Neither of the two new HP 94 black ink cartridges works. When I reinstalled the used cartridge, I also got the "Print cartridge faulty or incompatible" message, in spite of the fact that the used cartridge had been working (albeit poorly) before I tried installing the new ones.

I saw the suggestion of contacting HP support, but my printer is 4 or 5 years old, which means they won't want to talk to me.

Any suggestions?

[Bob_Headrick · Accepted solution]

The troubleshooting steps in this page may help resolve the issue.  Also check the carriage to make sure the x-bias spring has not become dislodged.  If the spring has become dislodged (1) and punctured the flex circuitry (2) the printer will require service.

[fmd3]

Many thanks, Bob. The x-bias spring had managed to slip out of its normal place.

You saved me lots of headaches!

With much gratitude,

Fred

[Bob_Headrick]

If the spring was dislodged but has not damaged the flex then you should be able to put it back in place (and perhaps hold it in the proper place with a bit of epoxy).  Even if you eased it back into place and it worked you should consider a dab of glue to keep it in place, lest you forget about it and damage the flex in a future cartridge change.

[fmd3]

Will do. As for the new cartridges that I opened, one is now in the printer and the other in my drawer. Should I bother putting tape over the head or will it be fine as long as I don't touch it?

[Bob_Headrick]

I would suggest not putting the tape back on, this can damage the black printhead (and would ruin a color cartridge).  For best storage I would suggest getting a small tupperware sandwich sized container and fold a piece of paper towel to fit the bottom of the container.  Put about a teaspoon of water on the paper towel, then put the cartridge in on its side.  Make sure the printhead nozzles do not tough the side of the conteiner or anything else.  Seal the container and keep it stored in a cool place away from temperature extremes.

[fmd3]

Bob,

Thanks again for going way out of your way to help me. 

Do you happen to have an iPhone? I am trying to figure out how to print something wirelessly with the HP printer.

Have a great week,

Fred

[Bob_Headrick]

I do not have an iPhone.  You might take a look at the forum here: ePrint, Print Apps, Mobile Printing, and ePrintCenter