Black Screen no Logo after Digitizer Replacement

After repair of cracked screen and new Digitizer my screen is totally black and I have no Logo what so ever or dim screen.

I have connected the iPad mini to my Mac and iTune and restored it to latest iOS 7.11 and copied all my programs, photos and documents from iCloud without any problems so the computer board is alive and works.

I don't have the micro instrument and skills neded to repair the Fuse or the 4R7 coil. My multimeter don't measure milli ohms. I can buy a milli ohm multimeter if needed.

I want to send the iPad mini CPU board for repair from Phuket Thailand.

My questions.

1. How do I find out if it is the fuse, the coil, the On/Off button or something else needed to repair based on the above info.

2. Where do I send the CPU board for repair and what is the cost.

Please advise

Sten