No, but if you're using a custom kernel, you'll brick the phone.
Totally Right, check very well what are you have on your phone then do what you want to do. Relock Bootloader can be possible with Stock Kernel only.
IF I HELPED DO NOT SAY THANKS, CLICK IT. My Evolution: Sony Xperia Z1 - UB + 4.3 Rooted + Deodexed, HTC HD2, HTC Diamond 2, HTC HD Blackstone, Nokia 7070 Prism, Qtek 9100, Nokia 3100, Motorola T720i, Nokia 3310, Sony Ericson PF 768 (Blue)
How Get Root on Sony Xperia Z1 with Locked Bootloader and the Latest Android 4.4
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