When you say 'SD Card Reader' do you mean the official Apple Camera Connection Kit SD Card reader? You also say that you 'updated'. I'm not sure, of course, from what version of iOS you updated from and to, but in the not-too-distant past, Apple reduced very considerably the current drive capability of the 'USB' connector so that many third-party card readers now no longer work. The Apple Camera Connection Kit works - of course! - but the new current drive capability is only 10 mA and very few third-party card readers can work with that current.
Tim