Nope, this is the STM issue. I had the same problem.
Esoeji bro, this problem happens when you force the "zoom" in when your camera powers off. As we know, the lens extends a little when focusing. Some people have the tendency to force this extension back by pushing it by force when they want to store their camera or lens.
It is not recommended to do so. For USM lens, I recommend retracting the extension by using focus ring. HOWEVER, the problem with this STM lens is that the manual focus DOES NOT work without power on. It's the same idea as the USM motor for 85L.
Thus, to prevent this issue, I suggest the following methods to retract the extension when you want to keep it:
1) Manually turn the focus ring while your body is powered on to retract the extension
2) Place your lens cap on and half press the shutter button. Since lens cap is on, lens will focus hunt by zooming from MFD to infinity. As such, the lens will extend to the max, then retracts to the minimum. When it is at the minimum, release your hold on shutter, and turn off your camera body.
The above will fix your problem. I doubt CSC can do sh1t about it, it's a design issue.
In anycase, if you do happen to force on (accidentally or not) the focus extension while power is off, when you turn on your cam, the AF will fail. To fix this, turn off your cam, disconnect your lens and connect it back.
Hope the above helps.
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