My 100-400 is having an IS malfunciton in manual focus mode with IS OFF

Over the weekend my 100-400 started freaking out. The whole image will sometimes snap up and down. The IS system is the clear culprit. This happens 13 months after I bought it, so it's out of warranty I guess. I had the lens on manual focus with IS turned off, and the IS system was just going nuts anyway jumping the image up and down (kinda at a diagonal). It would seem to work when the IS was turned on, then went back to jumping up and down when turned off. I've been sitting here playing with it trying to get it to act up and I can't figure a specific cause.

Anyone else experience this? Solutions? If I drive down to Irvine tomorrow how many weeks will my lens be in the shop and how much will it cost to fix, I wonder

-K

That sounds really odd. Canon may surprise you. I have had them fix known issues on gear which is several years old for free, without even asking, when I sent it in. I have not had any repair bill over $140 even for a lens I dropped, and the turnaround was less than a week. So, do not fear sending it in.

kurt765 wrote in post #12782040
Over the weekend my 100-400 started freaking out. The whole image will sometimes snap up and down. The IS system is the clear culprit. This happens 13 months after I bought it, so it's out of warranty I guess. I had the lens on manual focus with IS turned off, and the IS system was just going nuts anyway jumping the image up and down (kinda at a diagonal). It would seem to work when the IS was turned on, then went back to jumping up and down when turned off. I've been sitting here playing with it trying to get it to act up and I can't figure a specific cause.

Anyone else experience this? Solutions? If I drive down to Irvine tomorrow how many weeks will my lens be in the shop and how much will it cost to fix, I wonder

-K

Happened to me. The IS unit was gone. Cost me $700 to replace. The IS unit still needs to hold it's piece of glass in place even with IS turned off. When my lens tried to do that it would slam that piece of glass around. I could only get it to stop by retrying to take a picture. Usually on the second try it would hold.

Oh %#@!
Tomorrow I will take it to Canon and I pray it's not that.... man that would suck. I bought this lens brand new.

-K

Warranty still valid. Woohoo! We'll see what they say now that they have it. The person who checked my lens in said "yep, it's the IS"

Hurray! All fixed up, re-calibrated, razor sharp. No charge. 2.5 day turnaround. Thanks Canon!

Apparently the IS system had become loose somehow. No new parts were needed.

Congrats. Was going to say...that behavior doesn't sound like anything OTHER than the IS unit being borked. Glad to hear they got you sorted out and it's working again!