Canon has issued a service notice for a collection of lenses with specific serial numbers that need to be checked for faulty focusing systems. The lens affected is the EF 24-105mm F4L IS II USM standard zoom, but users are advised that only particular production batches have the problem.

Canon says that some units with serial numbers beginning with 48, 49, 50 or 51 suffer from poor focusing when used with an AF point close to the edges of the host camera’s focusing array. The fault is only apparent when the lens is used at wide-angle focal lengths.

All defective lenses will be taken back for testing and repair at no cost to the owner, the company says. The Canon website carries a service section that allows owners of the lens to type in the serial number of their lens to check whether it will need to be returned.
For more information see the Canon USA, Europe or Asia service pages, or those for your local area.

Manufacturer's information

Service Notice: EF 24-105mm f/4L IS II USM Lens

Thank you for using Canon products.

We have determined that some EF 24-105mm f/4L IS II USM lenses exhibit an AF operation-related malfunction. The details of the phenomenon and Canon’s service policy are described below.

We would like to offer our sincere apologies to users who have been inconvenienced by this issue. Going forward, we will spare no effort in our quality management to make sure our customers can use our products with confidence.

At the wide-angle end, focus is not achieved properly when a peripheral AF points are selected, regardless of the AF area selection mode.

Affected Lenses
If the first two digits in the serial number (see the image below) of your lens are ”48”, ”49”, ”50” or ”51”, then your lens MAY POSSIBLY be affected.

How to check if your lens is affected:
1. Click the search button below to display the serial number input screen.
2. Input your lens’ serial number (10 digits) and then click the [Submit] button.
* Please double check the serial number you entered before you click the [Submit] button.
3. One of the following three messages will be displayed.
“Your lens is NOT an affected product”?
“Your lens is an affected product”
“Invalid number”

As soon as preparations have been completed, we will inform users about the start date for accepting support requests for lenses affected by this issue.

Potentially affected products will be inspected and repaired free of charge. If you own one of the potentially affected products please contact our Customer Support Center