Hi Jennifer1. "I feel your pain"... the way the printhead is installed and connected is a really bad design. Engineers working at Canon would, should, know this and rectified it, AND as happens in most responsible manufacturers, issued a world-wide recall - just like car manufacturers have to...
So, have you read my post above about fixing my MG7160? I know its a different model, but the principal is still the same. In my case what fixed it was getting the contact between the printhead and the electronics 100% correct. That's why I said I cleaned the printhead contact patch with iso, even though it looked clean. And by pushing the head home then clicking the locking lever in place, rather than using the lever to pull the head in contact, meant it definitely IS connected.
And... It worked, as I said, and now, almost 2 years later still works fine. I print with it at least 2 or 3 times a week (which keeps the ink from drying out in the head), and the quality is still good. It does have an alignment problem, but it's not affecting the output.
It did have a related problem a few weeks ago, it rejected a cartridge. I re-installed to old one and it was ok (but out of ink). Another cartridge was ok, so it proved to be a faulty cartridge. Not a Canon one, I buy the cheapies off ebay for about $25 for 2 sets of long life cartridges.
