E16 on a black screen at camera startup?

ianwoodsokehampton, E16 Error is a Canon generic error code and it means that there are issues with the lens mechanism and it cannot contract/extract/focus etc. That is the reason why it works in playback mode, since it does not have to extend the lens. Try a new/different brand of batteries and see if that makes a difference. If not, you should take a look at the lens cable, check for corrosion or even a broken cable/connector. If all that looks good, consider a new lens. Hope this helps, good luck.