Bonjour,
pour finir j'ai reussi a refaire marcher ma Pixma-170. Mail il me fallait la demonter et remonter. Je n'ai rien trouver de speciale, mais j'ai profiter de nettoyer un peu partout. Une fois remonter elle c'est mis à marcher, heureusement.

Vouz pouvez aussi essayer ceci (info de Canon helpcenter, en anglais)

"Dear Customer,


Thank you for your recent enquiry regarding your Canon product.

Please find below a step-by-step guidance that will help you resolve the problem:

1. Try cleaning the paper feed roller. Press [Menu] repeatedly until <MAINTENANCE> appears. Use [<] or [>] to select <ROLLER CLEANING>. Repeat 2 times without paper loaded in the machine and then 2 times with paper loaded.
2. Make sure that the appropriate paper type is used. Check to see if the paper you are printing on is not too thick or too thin
3. Make sure that the media is not curled, or damp.
4. Make sure that the media type is selected correctly in the printer driver. On the [Main] tab of the printer driver, ensure that the [Media Type] selected matches the paper loaded.
5. Make sure that the paper is loaded correctly. Load in the portrait orientation regardless of the print direction of the Auto Sheet Feeder and slide the paper guides against the paper stack (but not too tight).

However, if the same error persists after all the countermeasures are taken, please turn off the printer, remove the power cord plug from the outlet for approximately 30 minutes, plug the power cord back in, and then turn on the printer again.
If the above steps do not solve the problem, we will advise you to have the printer checked out by a Canon engineer, as this would indicate a malfunction with the paper feed unit.

Please click on the link below to visit the Canon UK website where you can find details of your local Authorised Service Facility as well as other important information needed to send your Canon product for repair: "

Bonne chance

Hugo