Thank you. There have been problems with the chat software tonight, so I've switched this session into Q&A mode. Q&A is slower, but always works.


I've extracted the page from the i850 service manual below that explains the problem:



The 7-blink code indicates that there is a failure in the printhead, the printhead carriage, or the printer's main logic board.

Reviewing this problem on the internet and in our own archives, replacing the printhead only works about half the time. Since the printhead is a $75 item, I can't recommend replacing the printhead when there is less than a 50/50 chance of success.

The other possibilities are failure in the printhead carriage or in the printer's main logic board. Repair is possible, but it is not generally economically practical.

In most repair facilities there's a two hour shop time minimum charge, with technician time at $US 65/hour. Then comes the cost of parts - figure a $US 50 minimum for parts. The minimum cost of having a printer repaired is $US 180. Then add another $US 40 for shipping if the repair must be sent off to be fixed at a regional repair center outside your local area, for a total of around $US 220.

The rule of thumb for repair vs. replace is repair only when the repair cost is less than 2/3 of the cost of replacement. Therefore, if you can buy a replacement printer for $US 300 or less, you're better off with a replacement printer.

There may be an escape hatch on the warranty, however. If you purchased the printer with a credit card (American Express and Visa are good on this), many cards double the manufacturer's warranty up to one additional year. If this might apply, check your cardholder's benefits flyer. If this does apply, contact your card supplier at the number in the benefits flyer to have the printer replaced or refunded.

Otherwise, the best choice is to purchase a replacement printer. In most cases, ebay is a good source for replacements. Used, refurbished and NOS ("New Old Stock") printers are generally available for all printers made within the last ten years. An identical replacement has several advantages:

1. Continue using the same printhead or toner cartridge (assuming it is removable, of course) and keep the replacement's unit as a spare.
2. Use up the ink / toner cartridges from the old printer.
3. Continue using any expendable supplies such as ink tanks or toner cartridges from the old printer.
4. Eliminates the need to remove existing printer software and replace it with different software -- always an "iffy" issue.

If you're satisfied with your i850, a very good choice is either an NOS or used i850 on ebay or from a local craigslist. They are readily available and not expensive -- see the ebay search below:

http://www.ebay.com/ctg/Canon-I850-Standard-Inkjet-Printer-/48462189?_refkw=i850&_pcatid=42&_ipg=&_pcategid=171961&LH_ItemCondition=1000|3000&_from=&_dmpt=COMP_Printers&_armrs=1

This will allow you to keep the existing software and use up any supplies you have for the existing i850.

A new printer is also a good choice, given that new all-in-one printers are on sale every week at office and computer superstores. A brand other than Canon would be the best choice. This is because when the Canon software is removed from the system, it will leave "stuff" behind. This leftover "stuff" is less of a problem when the new printer uses software completely different from the Canon software.

Summary: Printhead replacement has a less than 50% chance of success. Repair is not economic when compared to the cost of a new printer. Replacement with a NOS or used i850 is a good choice; replacement with a non-Canon unit is also a good choice.


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