Which error code are you receiving back from iTunes? The answer is most likely in a sequence of reboots. Unless the iPad air 2 has endured abuse, it should not be a hardware issue yet, if it is it would be an anomaly.
The blank, “dead” screen / apple logo that your iPad is experiencing during restore attempt is most likely a simple fix. There are 3 button sequences, that “resurrect” any i device when you think you’ve lost it forever. The key is in accurate timing & to perform each of these button sequences in a timely manner & in the correct order is of paramount importance (if you want your device up & running the 1st time, every time.
Here they are:
1. HARD POWER RESET/REBOOT – Hold down power button for 5 seconds, while keeping power button depressed, push home button for 10 seconds, finally release power button & continue to hold home button by itself for additional 20 seconds. Total Hard Reset Time – 30 seconds – no longer – if 30 seconds is exceeded, next reset cycle will begin to overlap & device will turn off & reboot progress will be lost.
2. SOFT POWER RESET – Begin to hold down power & home button simultaneously; continue to hold down both buttons for 10 seconds. Total Soft Reset Time – 10 seconds – no longer.
3. RESTART “KICK” START AFTER CRASH – Begin to hold down power & volume up button simultaneously, continue to hold down both buttons for 10-15 seconds. Total Reset Time Varies – depending on the reason / severity of the device failure.
Hope this helps!