Ink sensors have gone haywire, codes 1681, 1414, 1410

[Daniel602]

Pixma MG 7520 won't print. This started after I replaced the PGBK ink, which was low. It randomly gives me these various codes, and randomly chooses any one or several of the ink cartridges to complain about. "ink tank cannot be recognized" or "you have two tanks of the same color" which of course is not true, they are all in their right places, Canon brand.

I installed the latest driver. I took all the tanks out and put them back in. I attempted a "hard reset" involving repeatedly hitting the power button while the printer is unplugged from power.

Mac OS Big Sur 11.2.3, Mac M1 Mini (2020)

[jtraumiller]

I have the same printer MG7520 and have the same error code 1681 "more than one ink tank of the same color" mine is the black ink tank.  I cannot get to any other screen to do maintenance or restart.  Turning the machine on and off, holding the start button down 10 seconds, and everthing else I have tried failed to change the error code.

It worked fine for several years, and now just stopped working.  I am very disappointed that the forum and Canon have no comment with regard to acknowledging the problem or offering a solution.

[Patrick]

Hi Daniel602 and jtraumiller,

All the error codes that you stated are related to the ink tanks.  If replacing all of the ink tanks does not clear those codes, your PIXMA MG7520 would require service.  You are eligible for Canon's Upgrade Program. This is for out of warranty units which have been diagnosed to require service, or for some reason are incompatible with a new or upgraded system. This option allows you a one-time opportunity to purchase a replacement product, discounted from the list price.

To help you get up and running quickly, we also offer free standard shipping (if the order is completed by 12:30PM ET). If you would like to take part in this option, please call our Sales Department at (866) 443-8002. Let them know you have been working with technical support and the Canon Upgrade Program was offered.

[jtraumiller]

Patrick,

Thanks for your input.  I finally discovered that the multiple ink tanks of the same type, (small BK) was not a conflict between the small BK and large PGBK, but between the small BK and the small GY tanks.  I had inserted a BK tank into the GY slot and it worked fine for a long time,  When I replaced the BK tank with a new BK tank that is when the error code came up. 

I bought a single Canon GY tank and replaced the BK in the GY slot and everything works fine again. 

I have very successfully used Jarbo ink Replacements since the printer was new without a problem.  Only recently has the 1681 multiple tanks of the same type come up as an error.  Something in the software seems to be more sensitive now than previously.  I guess having a supply of the GY tanks is a new priority for me.

[Burrilliance]

I was checking this area out as I had the same problem. I watched a video on cleaning or replacing the print head but that didn’t do anything.
I may have been lucky but here’s what I tried.
For my, it was grey that wasn’t being recognized. I swapped my old grey cartridge and put it in the black spot, and put the black in the grey. Worked instantly.
So then I put my full grey cartridge where the black cartridge was. It then read me an error of having too many of one color. So then I pulled out the old grey cartridge that was in the black spot, and then put the black back in so they were all in the right spot. Sort of felt like I was trying to trick it. And sure enough, it seemed to work. And yes, I’m using cheapy knockoff cartridges.
Good luck!