Copier problem I have a Brother 420CN. A message about no cartridge keeps apparing. All the cartridges are in and have ink in them. I've reinstalled them a thousand times yet the message keeps appearing. Help!

I recently purchased a two pack of lc-51bk cartridges. I had this problem with one of them. I noticed that that cartridge is physically different than the one I removed. There's a little beige tab that was missing. What's interesting is that the other cartridge in the pack had this tab, and everything worked perfectly. The cartridge seemed to be defective.

I had the same problem on my MFC640CW until I realized that I wasn't opening the scanner cover completely and not putting the stand up otherwise the mfc thinks it hasn't been opened to change cartridges yet.  I hope this helps Good Luck

Remove the ink station assy & check that theres no ink spillage over the cart' sensor pcb.if there is, clean then refix & reinstall
assy.
If that does'nt work a new pcb will be needed.

I had the same prob yesterday and just fixed it now heres the message i posted in response to my plead for help.....

Nothing would keep the machine from not seeing a Cyan cartridge installed. I opened
the catridge door, removed the Cyan cart,used a long piece of paper to block the sensor, then used something to push the cartridge door sensor to think it was closed.
This then brought the machine alive happily believing a Cyan cart was installed. This just proves the sensor was ok....so then I applied tape over one side of the sensor and installed the Cyan as per usual and the machine is now functioning again.

This fix will work for any color and as long as the sensor itself is working properly. For some reason the cartridge itself was not blocking the light path from the sensor sufficiently causing it not to see the cartridge installed. Usually the ink level will block the sensor......anyway this piece of junk dodges a bullet and lives for another day...but who knows for how long...the more ink i got on me the closer it got to a date with the pavement.

Solution is to not buy any brother products...more junk for the recycle pile

There is NO solution for this problem, I would like to fix it myself
BUT Brother will not sell repair manual to end user see their response that follows. A used MFC-440CN on flea bay goes for $0.99 and new for $50. Mine will be sent to local recycle dump!!!!



“Thank you for the e-mail. I do regret to inform you that your request for a repair manual is not an option we have to send to you. The repair service manual is only available to Authorized Brother Service Centers. You as an end user will only have access to the instruction manual.
We understand your frustration but here at Brother, we do not support consumables which are not manufactured by brother. When you replace the consumable in your machine by another brand, this may cause damage to your machine. Most non-brother consumables are not designed the way as which we design our consumables. They are manufactured to work hand in hand with the unit.
As you mention below, you are no longer under Brother Manufacturer Warranty and our written documentations state clearly we do not support Non-Brother Consumables and may void the warranty of your machine if this is what caused the damage. With that said, unfortunately we may not support you further but if you wish to have your machine repaired, you may bring it in to any of the repair centers Authorized by Brother that are found below for a repair. Please note that when you bring in your machine, there is a service fee for estimation.
Brother International stands by its products and strives for excellent customer service. We would have tried our best to accommodate you but you have tied our hands with the 3rd party consumables.”

Try to uninstall the drivers of the printer and reinstalling them again.