Try a hard reset. remove the lens, memory card and battery, set the mode dial to M (manual), and switch the camera to the ON position.Allow the camera to sit idle for 30 minutes. Then, switch the camera to OFF, re install the battery, memory card and lens, switch it on, put the mode dial in auto and with the CSM lever in S press the shutter release half way. Please let me know if the AF works .
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