No shutter actuation, no menu display, no autofocus.

Try using manual focus - if the autofocus won't work, because of low light, then you can't take pictures.

Sounds like the shutter control is not active. If closed, the shutter will not allow light to enter and thus you have a black receptor. Take to a camera shop for testing.

Hello

Thank you for using FixYa for your problem

Always check the batteries first but if is it still giving the same fault, your camera is faulty.
It should be taken to an authorized repair centre for a repair estimate. Very few digital cameras have any user-serviceable parts.

Please rate our solutions and if you still have problems please call back for more ideas to help you

Thanks
Richard Scott
Technical Support
New Zealand

If the images are recorded on the card but not shown immediatly after the shutter release, press MENU, go with the control dial to the recording menu (the one symbolised with a camera) and press AF, the center knob.
On page 1, the third item controls the instant playback, it can be set to OFF, probably your setup, 2, 5 or 10 seconds.

Press the MENU button, select "Drive Mode," then select the self-timer (one-handed clock). To start the self-timer, press the shutter release button.

I have an 5D with the same problem, It looks like the Anti shake does not initialize properly, The only bypass I found that worked (except for a real repair) is to set the display light timeout for 5 seconds, The standby timout for 1 minute, Turn the camera off, and on again, Wait for 5 sec then the display goes blank, wait for 1 minute then the camera goes in standby, (light from CF card flashed red 1 time) Then touch any button to re-activate the camera and... voila... everything works, including taking normal pictures and the anti-shake !!! So it only takes a minute everytime to startup..

The canon 5d was suspected to produced low sharp pictures, but it's wrong. Sharpness is a parameter on the 5D. You can tune it in the menu/image style/ then you choose your style and hit "jump". The first cursor is sharpeness. Enjoy.

The AF point will luminate very briefly when you press the shutter half way. To change the AF points press the Zoom in button + and then use the dial on the top to select the point you want. If you are not able to do this go into the Menu setting and under custom funtions go to No. 13 and set this to 0:Normal.

To get the image to focus and remain focused while you recompose set the shooting mode to 'One Shot' do this be pressing the AW-WB button them turning the top dial to get to 'One Shot'. When in 'one shot' press the button half way recompose whith out lifting your finger and squeeze all the way when you have recomposed.

Hope this helps.

It would seem this problem has frustrated other users, read this thread on photo.net

If it works in other ways, autofocuses, seems to lock on and is ready, but the shutter won't release,  and if when you turn it on, there's a buzzing sound for a few seconds, and if you turn on the AS button and when you press the shutter release part way you see five bars blinking on the right side of the viewfinder, you've got an AS system failure, and will have to send the camera in for service.

http://eservice.sony.com/webrma/web/index.do