I know this is a little late. I had the same problem, and I thought that I would publish how I earned in my case, just in case, if this helps someone in the future. I turned it on on the iPad and it didn't show. I tried closing Safari on the iPad by disconnecting and reconnecting the cable, and none of them worked. It turned out to be very simple for me, I just left Safari on my laptop and restarted it, and Safari recognized the iPad and allowed me to debug. It may not work for every case, but it was for me, hope this helps.
edit: just a note, I had an iPad connected using a web inspector when I restarted Safari.
Robert-W Jun 03 '14 at 2:57 a.m. 2014-06-03 14:57
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