Brother MFC 9340CDW
The toner doesn’t seem to be adhering to the paper

Experienced technical support provide their insights in answering this question :
That would indicate the fuser is not getting hot. Of course, that should cause an error and shut down the printer. Could be a piece of paper wrapped around the heat roller preventing the transfer of heat to the printed sheet.

How to Identify and Fix Common printer Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced technical support :

One of two issues can cause this. The toner cartridge may not be fully seated into the photoconductor unit. This can cause the seal between the two to break, allowing toner to leak out. The other possibility is that the toner cartridge or the photoconductor unit may be damaged.
If the contacts between the cartridge and the printer are dirty or clogged, there is a high chance that this can be the main cause for the ink to leak on the paper. To properly clean the contacts, open the printing machine and remove the ink cartridges and place them on a clean piece of paper.
To fix toner streaks, first, print several blank pages to see if it fixes the print quality. Next, try cleaning the internal components of the printer such as the laser scanner/mirrors. If this doesn`t work, re-install the toner cartridge.
The most significant cause of leaking carts is a user error; incorrect assembly or replacing old parts with incompatible pieces that don`t make sense with the device can lead to leaks. To avoid these disasters, ensure that all connections are secure and seated adequately so that nothing works itself loose over time.
A toner cartridge that is leaking or has leaked inside the machine will need to be replaced. Do not remove the toner cartridge from the Brother machine until you are ready to replace it. Excess toner can be cleaned with a soft, dry, lint free cloth before replacing the cartridge.
If an ink cartridge is leaking, put it in a sealed plastic bag. Then you may be able to return it to your retailer for a replacement or refund, depending on your retailer`s policies.
On your computer, in the Windows Notification Area (bottom-right corner of your Windows desktop), right-click the printer icon. In the printer menu, select the Properties or Preferences option. In the printer settings window, the ink or toner levels are displayed for the currently-installed cartridge(s).
“Toner Error” will appear on your machine`s display if one or more toner cartridges are not installed or not installed correctly.
A fuser unit is a pair of heated rollers within the printer that fuses the toner onto the paper being printed on. Toner particles are pulled to the paper to create the desired text and images as the paper passes the imaging drum.
Use a lint-free cloth dampened with 91% isopropyl alcohol to wipe both the cartridge and inkjet printer`s print head. This will clean the contacts of dirt or clogs. To test if cartridge is damaged, wipe its entirety with a dry lint-free cloth.
Missing colours, streaky prints, smudges and ink blotches are all signs that your printer ink or toner cartridge may be damaged. Some printers will actually warn you if a cartridge is damaged and will refuse to print. This includes HP ink cartridges, Samsung toner cartridges and Canon ink cartridges.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Brother toner cartridge low toner override
ANSWER : Thank you. You are a genius. Of course this is not a substitute for cartridge replacement but it is great for extending the life of the color cartridges and allowing you to continue to print until you can get new cartridges.

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Brother MFC 9340CDW

toner loose
ANSWER : That would indicate the fuser is not getting hot. Of course, that should cause an error and shut down the printer. Could be a piece of paper wrapped around the heat roller preventing the transfer of heat to the printed sheet.

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Brother MFC 9340CDW

Brother toner cartridge low toner override
ANSWER : follow these steps:

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Brother MFC 9340CDW

Expired Toner and Suggestions for Source of Toner
ANSWER : Hi Frank, I had a very similar question two weeks ago, but my “old beloved workhorse” is an HP Laserjet 4L. From the good old days! I too had made bad investments in “new but old truly HP” toner cartridges, hoping to coax more life from my printer. I ended up choosing to try a remanufactured cartridge from www.4inkjets.com. It was a gamble, but the website said they had a 100% satisfaction guarantee. And I can tell you they have lighting fast service. I’ve now printed 50 pages without a flaw. JOY! While the cartridges and technology are different, I suggest you try the same place. And good luck!

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Brother MFC 9340CDW

Toner not transferring
ANSWER : What mostly goes bad in toner cartridges is the drum wiper blade. They deteriorate in new sealed cartridges. Toner caking up, not so much.

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Brother MFC 9340CDW

toner cartrigdes and drums
ANSWER : You can, but there are good knock-offs and bad ones. I’ve run into ones that come totally empty. Ones that don’t have the chips installed that identify themselves to the printer. Ones that have sat on a shelf for years and fail on installation. I could go on, but I’m sure you get the idea. I use http://directpreciseimaging.com/ Mostly because I set him up in business and he’s local to me. I have very few problems with his products.

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Brother MFC 9340CDW

Toner cartridge full, printer displays: "empty needs replacing"
ANSWER : I once went to a customer who had a similar issue. They had installed new cartridges and judging from the box, they looked OEM. Strange thing was they felt empty when lifted and they were missing the chip on the outside that tells the printer it is installed and keeps track of how many copies were printed with that cartridge. The printer has no other way of knowing if the cartridge is full or empty.

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Brother MFC 9340CDW

Toner chip resetter or cheap replacement source
ANSWER : There is a chip resetter if you can find someone who sells it. http://apexmic.info/how-to-reset-chip-dell-1250c.h…Otherwise, do a google search on dell 1250c reset chips. There are lots of suppliers.

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Brother MFC 9340CDW