17-40 mm has stopped autofocusing

[farijee]

Dear All,

I have been using the 17-40 mm L on my 20D for almost an year now. Since yesterday the lens has stopped autofocusing. This is really strange, since nothing has happened that can explain this behaviour. The lens hasn't banged anywhere or fallen down, the contacts are still shining. Plus I have checked that the problem is with the lens, since another lens (EF 50mm) works very fine with the 20D. And the 17-40 mm exhibits the same problem with my older EOS 300V.

Now this is the problem: In the AF mode, when the shutter button is half-pressed, nothing happens. The lens has simply stopped autofocusing. Of course I have checked that the lens AF button is selected. Otherwise the lens is okay, e.g. if I manually focus with half-pressed shutter, the camera beeps when the focus is achieved.

Could anyone explain what might be the case? Is it sth to do with the USM mechanism? Is the lens motor dead? I really hope someone can understand and locate the problem and offer some advice.

regards,

Farhat.

[bob mccarthy]

Try the lens on another camera.  If you don't have a back up body go to a camera store or call a friend.

Doesn't sound good though.

Bob

[Paul Sumi]

No error codes on the 20D?  Have you tried cleaning the contacts on the lens and camera body, oxidation doesn't necessarily dull the color.  If that doesn't work, sounds like a trip to Canon for repair.

Paul

[farijee]

No error codes on the 20D?  Have you tried cleaning the contacts on the lens and camera body, oxidation doesn't necessarily dull the color.  If that doesn't work, sounds like a trip to Canon for repair.

Paul
[a href=\"index.php?act=findpost&pid=55905\"][{POST_SNAPBACK}][/a]

I have tried the lens on another camera, and it doesn't work, I mean the lens does not work. Whereas another lens works perfectly on my 20D.

This is the strange thing. The lens has stopped working all of a sudden. Nothing has happened to it. The contacts (on the lens as well as the camera) are still shining. Plus I think it is not a contacts problem, since if I manually focus in AF mode, the camera beeps if focus is achieved. Plus if I change the AF switch on the lens to MF, the indication on the camera changes, which means that the lens is communicating with the camera. Its just that the autofocus is not working.

Has sth like this happened to anyone else? I assume the lens gets its energy from the camera, or is it that there is some hidden battery somewhere in the lens to drive the USM motor?

I never thought something like this could happen to an L series lens.

regards,
Farhat.

[Paul Sumi]

Unless someone else comes up with another idea, send it back to Canon for repair.  It's still under warranty and should be a free repair.  You don't say where you live, but I've had a very good experience with Canon U.S.'s west coast repair facility in Irvine, California.

L lens doesn't mean that nothing will ever go wrong.  A mechanical or electronic part can fail even on the most expensive equipment even if you are very careful with it.  

By way of example, my 1D Mark 2 (Canon 1 Series DSLRs should be indestructible, right?) fried a circuit board, one month out of warranty.  Canon did the right thing and fixed it for free, but this just shows that any piece of equipment can fail.

Paul

[farijee]

Unless someone else comes up with another idea, send it back to Canon for repair.  It's still under warranty and should be a free repair.  You don't say where you live, but I've had a very good experience with Canon U.S.'s west coast repair facility in Irvine, California.

L lens doesn't mean that nothing will ever go wrong.  A mechanical or electronic part can fail even on the most expensive equipment even if you are very careful with it. 

By way of example, my 1D Mark 2 (Canon 1 Series DSLRs should be indestructible, right?) fried a circuit board, one month out of warranty.  Canon did the right thing and fixed it for free, but this just shows that any piece of equipment can fail.

Paul
[a href=\"index.php?act=findpost&pid=55920\"][{POST_SNAPBACK}][/a]

Well yes I'll wait and see if someone else has had a similar problem. Otherwise of course I'll have to get the lens checked. But this too is very tricky. I bought the lens in Germany, a few days less than 1 year ago. After that we moved back to Pakistan permanently. Now the lens has a European 1- year warranty, and incidently I'll be visiting Germany week after the next, a few days before the 1-year period runs out.
What I could do is bring it back to the shop where I bought it from, and then see what they tell me.
But is there a right guideline to follow if sth happens to equipment which you buy in a country different from the one where you live?

regards,

[Paul Sumi]

Well yes I'll wait and see if someone else has had a similar problem. Otherwise of course I'll have to get the lens checked. But this too is very tricky. I bought the lens in Germany, a few days less than 1 year ago. After that we moved back to Pakistan permanently. Now the lens has a European 1- year warranty, and incidently I'll be visiting Germany week after the next, a few days before the 1-year period runs out.
What I could do is bring it back to the shop where I bought it from, and then see what they tell me.
But is there a right guideline to follow if sth happens to equipment which you buy in a country different from the one where you live?

regards,
[a href=\"index.php?act=findpost&pid=55935\"][{POST_SNAPBACK}][/a]

Your situation is more complicated than I thought.  You might contact Canon in your region as soon as possible to ask them how best to proceed.  I would think that they'd honor the European warranty.

Paul