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Error 1851 on Canon Pixma Pro 1

Dear colleagues,
After some (around 6) months of inactivity, I had to put back on service a Canon Pixma Pro 1 that until the day I used was working perfectly, and it worked for 8 years without any issue.
When turned on I noticed immediately the yellow light blinking..
I decided to send a test print, but as soon as the test print is listed on the printing queue, I get the error 1851: Inner Cover is open.
Of course the inner cover of the CD tray is not open, and I didn't find any way to let the printer recognize the cover closed. (reset, disconnecting to power supply, open and close of the cover hundreds of times, ..)
Online it seems nobody had this issue.
Please, do you have any idea on how to fix? Is there anything I can do to bypass or solve the issue?
Thank you

Product Expert
Product Expert

Hi! Thanks for posting in the Canon Community Forum. I see that your PIXMA PRO-1 is experiencing an 1851 error.


I see that you have checked the inner cover and made sure it is closed. If you want to make sure that you are looking at the correct cover, please look at step 2 in the following page of the online manual:


That illustration shows the inner cover being opened. If you have not done so, I recommend opening the inner cover to make sure there aren’t any obstructions (paper or loose object) keeping the cover from fully closing. If you don’t see any obstructions on the sides of the cover, check if there are any pieces that may have broken or become loose.


The following section of the manual will show you how to use the lamps on the printer to determine the error that is occurring:


If you cannot tell what may be making the error come back, the printer will need service. We do not have service options for this printer. You can check if there are any local printer repair shops or electronic repair shops that can help.


You are eligible for a discount with Canon's Upgrade Program. This option allows you a one-time opportunity to purchase a new or refurbished product that uses Canon’s newest technologies, including such features as built-in WiFi, Airprint and Cloud Print, carries a one year limited manufacturer’s warranty, and to help you get up and running quickly, we also offer free ground shipping.

If you would like to take advantage of this option, please call our Sales Department at (866) 443-8002 from 9:00 A.M. to 9:00 P.M. (Eastern Time), Monday through Saturday. Let them know you were getting support on the Community website and the Canon Upgrade Program was offered.


I hope this information helps. Thanks again.


I have the same problem with a Pro-100.  I have tried EVERYTHING to close the error!  Canon support has NO fixes or referral for repair.  I have looked at the problem every way and not been able to resolve the issue.  This was an expensive (for me) printer and it is crap because of a STUPID error.  I will never recommend Canon equipment of any kind to anyone.  I WILL recommend that they do NOT purchase Canon equipment, every chance I get.


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