canon 18-135 is focus problem after 50mm

[wavetrust25]

Hi guys!

I have a canon 18-135 is lens which gives me trouble. It's bought second hand. It will not focus after i zoom above 50mm. in the 18-50 are it works perfectly. as soon as i zoom after 50mm, it focuses really hard, sometimes not at all. the motor keeps buzzing, without getting any focus. at times, the focus after 50mm works.

at the same time, in av or manual, etc, mode, i cannot set th3 f stop below 5. it-s a 3.5-5.6 lens, but even at 18mm it will not set the f stop below 5. above 5 it works, no problems. below 5 no way. i scroll and scroll, and it stays at 5.

It's not from the camera. the camera is a 50d and any other lens work great.

any ideas on what's wrong and how to fix it?

thanks!

[pjmacd]

I'm not sure what's wrong, but since the lens is second hand, I would try to get your money back from the seller, particularly if it described as being in good working condition.

[arnold7d]

I have the same lens and anything beyond 50mm isn't sharp at all.