Here this how to reset ink level canon pixma MP170


Turn the printer off. 
Hold the button Resume / Cancel (red triangle in the circle), click POWER - indicator lights green. 
Release the button Resume / Cancel, keeping POWER. 
Click Resume / Cancel 2 times, keeping POWER, and then release all the buttons. 
When the indicator light Green - click Resume / Cancel 4 times! 
Turn the printer off button POWER.
Hopefully can help you to reset ink level canon pixma MP170