Canon BJC 7000 - Manual (Page 55)

You may need to replace the BJ cartridge or a BJ tank when any of the following
conditions exist:
o Poor print quality
If you notice a deterioration in the quality of printed pages, perform a test
print and clean the print heads before you decide to replace the BJ
cartridge.
o 3 Beeps
When the BC-60 Black BJ Cartridge runs out of ink, the printer will beep
three times and stop printing. Replace the BC-60 Black BJ Cartridge.
o 4 Beeps
When the BC-61 Color BJ Cartridge and BC-62 Photo BJ Cartridge runs
out of ink, the printer will beep four times and halt printing. Replace the
color BJ tank.
o It's a good idea to replace the BC-60 Black BJ Cartridge if it has been in
use for more than one year.
Canon has more engineers dedicated to creating quality ink for providing
the best results for output on Bubble Jet printer than any other
organization. Canon does not prohibit the use of third-party inks and the
use of third-party inks does not invalidate the product's limited warranty.
However, Canon cannot guarantee the quality or performance of your
printer when you are using inks from other suppliers.
Canon's limited warranty does not cover damage caused to Canon's Bubble
Jet products that is attributable to the use of third party parts or supplies,
including inks. The limited warranty remains in effect for its life one that
particular damage has been properly repaired.
For optimum printing results, Canon recommends that you use only Canon
BJ cartridges and BJ tanks.