Try performing a hard reset on the camera by removing the main battery, memory card, and the date battery using the information below. Once these have been removed, turn the camera to "ON" and allow it to sit for ten minutes. Turn the camera to "OFF", reinstall both batteries and the memory card. You will need to reset the time and date. This will eliminate the camera body as the cause of the problem.
If the lack of AF response of this single lenseremains consistant, then either the focus motor (located inside the lense) has failed, or the internal ribbon cable (providing power and control) is broken.
Canon charges around £125 to repair this problem.
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dependent on the accuracy of your description of the problem. As with
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see or touch the camera, and relies on the customer's manual dexterity
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