Cem geçmiş olsun. internette arattım, DPReview da aynı problem yazılmış. Özet yanıt şu:
It wasn't clear if you understood the previous poster was talking about removing the small battery that powers the clock and retains settings when the main battery is out of the camera. If you have already tried removing both batteries to force a reboot, there is not much else you can do. Send it back.
BTW this is not a common problem, so I wouldn't use it as the basis to choose between a 5D3 and a 6D, but if you want another 5D3, that's certainly a good option if you can justify the cost.