Hi hickpop
From your description, it appears that the toner cartridge may be malfunctioning. Please note we are unable to guarantee your print quality when using third party toner cartridges. At this point, to determine whether the issue is with your MF726cdw or with the toner cartridge, I suggest you replace your toner cartridge with a Genuine Canon toner.
Once you replace the toner cartridge, please clean the fixing unit. For your convenience, I have provided the steps below on performing the recommended cleanings:
To clean the fixing unit, perform the following procedure. Note that you cannot clean the fixing unit when the machine has documents waiting to be printed. To clean the fixing unit, you need plain A4 or Letter size paper. Set the paper in the paper drawer or manual feed slot ([ Loading Paper in the Paper Drawer ] [ Loading Paper in the Manual Feed Slot ]) before performing the following procedure.
NOTE
- Cleaning consumes the toner cartridge. Make sure that there is sufficient toner cartridge remaining beforehand. [ Checking the Amount Remaining in the Toner Cartridges ]
1. Press ![]()
and tap <Menu>.
and tap <Menu>.2. Tap <Adjustment/Maintenance>.
3. Tap <Clean Fixing Assembly>.
4. Read the message that is displayed, and tap <OK>.
5. Tap <Start>.
- Cleaning starts. When the <Finished.> message is displayed approximately 1 minute later, press
![]()
to return to the <Home> Screen.
Transfer Belt
Dirt may adhere to the transfer belt inside the machine and cause the print quality to deteriorate. To clean the transfer belt, perform the following procedure. Note that you cannot clean the transfer belt when the machine has documents waiting to be printed.
1. Press ![]()
and tap <Menu>.
and tap <Menu>.2. Tap <Adjustment/Maintenance>.
3. Tap <Clean ITB>.
4. Tap <Start>.
- Cleaning starts. When the <Finished.> message is displayed approximately 1 to 2 minutes later, press
![]()
to return to the <Home> Screen.
If you continue to have difficulties, please contact our support group using the following link:
http://Canon.us/ContactLI