iPad 3 cellular with iPad 3 wifi firmware

[geiologger]

Hi, my name is Rogerio and im new in this Forum and since im a brazilian guy my english is not that good, so im asking antecipated apologies.
So, i've bought an used Ipad 3 and the guy who sold it to me, told me that it is an Ipad 3 WiFI. But when i took out the smart cover, i saw a SIM CARD entrance. I 've opened it and putted my MicroSim in it, but my Ipad Firmware isnt a CELLULAR firmware and the MENU of the ipad dont give me an option to setup the 3G/4G ( I've checked the Model of my Ipad and it is a trully Cellular model. So, i've downloaded the CDMA Firmware, but when i try to install it using ITUNES i get a message that says the version im trying to install, isnt compatible with my FIRMWARE.
BONUS : My Power Button ( on/off) works perfectly to turn ON or turn OFF, but doesnt work to LOCK the screen down.
Please, if im using the wrong section to ask, my apologies again.

Thank you guys ! hope someone can help me =D

 

[sanke1]

You can't use WiFi firmware on cellular model and vice versa. You also cannot use CDMA firmware on GSM or vice versa.

Best way is to put your iPad in DFU mode by keeping it connected to iTunes on PC. Then do a restore so that iTunes downloads the right firmware based on your device type.

It will guarantee that correct firmware is installed.

 

[Atreyu25]

It is possible that you bought a hacked iPad that was blacklisted for being locked with find my iPad. There are hacks to make them wifi only but you probably have a bad iPad.
[doublepost=1459906857][/doublepost]Really nasty iCloud bypass hacks out there that turn cellular iPads that are locked into wifi. Sadly it looks like that for you.