My camera (same model) I bought about over a year ago did the same thing. I am doing more research and I'm finding out that this model has quite a lot of other problems like the memory card error issue which I just started getting also. I'm SOL (so out of luck) on this one. I did not attempt to fix it because it would cost the same to get a new camera with better features. Did your fix help?
I have a problem with my second Canon S400 ultracompact digital camera (the previous one had the dreaded E18 lens problem which).
The dial used to switch between print mode, video mode, panorama mode, etc. does not work. Fortunately it's stuck in the default "regular" single-image mode which is my main use for the camera.
Any suggestions? Now that I have purchased yet another digital camera, I am about to try to rescue this feature on this one by pulling out the little wheel to see if it's a mechanical problem.
The quality of these Canon S-series ultracompact digital cameras is NOT very good.
Thanks for any help.