Ink tanks full but blue ink wont print on my Canon MP190

you can't solve it by yourself. even if you clean the pads or rinse it with water. the ink absorber counter was still in error, so has to be reset. but no reset software for MP190 to date exist.

but to start, the same logic apply for MP160, that will hold true for MP190, the eprom chip holding the ink counters has to be erased or overwritten.

btw, some IC's are marked QK1-3696 obviously the MCU. TPC8778, K824Q, SN0507087 and more. MP190 main board is QK1-5045-02. and there one more IC. so one of this is the eprom chip holding MP190 's ink level,counters that need to be preprogrammed.
oh, that has to be in low level printer mode. see google for procedure on putting the printer into low level mode, same with MP160.

Were the cartridges new? if they were used they would need to be reset. Also you can go onto the Canon website and that should help too.

http://www.usa.canon.com/cusa/support/consumer/printers_multifunction/pixma_mp_series/pixma_mp190#ServiceAndSupport

In printer utility settings, you have to modify the ink cartridge settings and specify that printer should use only black ink cartridge. Click apply. Then press "stop\reset" button for 5-7 sec. and then release
it. Then it will work!

Ink level counter (program) didn't read actually ink at ink tank. Brand new cartridge ink level counter 100% (full), and ink 100% (about 10 ml). After may printing, ink will dry out, and ink level counter reach zero (ink out). Printer will not allow print anymore, even have refilled, because ink level read "ink out". For canon type, you just to release ink level counter, and counter just stop, but printer will allow to print. Press stop/reset button for about 30 second.

yes this is true, the ink tanks have little chips on them that know how much ink they have and how much approx has been used by the type of printing done, when the chip thinks the ink is empty it tells your printer, then your printer tells you.
you could get a chip resetter then be able to refill your tanks, or get a ink refill system for your printer £50 ($90USD) and is well worth it.

Are you using the right cartridges? They should be:

• PG-40 BLACK (Black Ink Tank)
• CL-41 Color (Color Ink Tank)

Also check this CANON FAQ:
How do I install the ink cartridge(s)?

That's the early warning for nearly full, in a little while it will change to waste tank full and will stop printing. You need to take it to a shop for new absorbers, and then have the counter reset.

I have a canon printer MP190. How do I do the reset after completing my ink cartridge to the syringe?

Buy HP instead Canon :) This is the only solution..