Hi PrabuBLR,
Thanks for visiting Apple Support Communities.
It seems like your iPad Air has not been working since updating to iOS 8.3. I know it can be frustrating to have unexpected issues after an update.
Since you were not able to restore your iPad, the next step to try is putting the device in recovery mode and starting the restore again:
To put your device into recovery mode, follow these steps:
- Turn off your device and leave it off.
- Plug in your device's USB cable to a computer with iTunes.
- Hold down the Home button on your device as you connect the USB cable. Keep holding down the Home button until you see the Connect to iTunes screen.
- When you see this screen, release the Home button. If you don't see this screen, try steps 1 through 3 again.
You can find these steps and more information about recovery mode in this article:
If you can't update or restore your iPhone, iPad, or iPod touch - Apple Support
Best Regards,
Jeremy