Hey there, I'm having issues with the wireless of my Wii U gamepad, It's losing the signal often and the message pops on the screen, as it usually does when you go out of range. But see the problem is, is that it does this even when I'm in the same room, my bedroom and I don't know why this might be. I do have large windows where the sprawling sunlight does come in in the mornings, but I don't see this actually being the case because when I play at night or in the afternoon when it's cooler, it still does the whole wireless thing, so I'm guessing it hasn't got anything to do with overheating.
Ok to be more helpful and give a better insight about this problem I need to say that, yes I do own a full HD, 32-inch widescreen tv, a Wii and a DVD player (all connected/disconnected) near my WiiU, But I don't think any of those are the problems though.
The only real concern may be the range at which my console is from our Wifi, I'm not sure if this is causing the delay or fluctuation in the reception of the Gamepad, but my Wii U is over 25 metres from our Wifi, yet it still recieves 2 out of 3 bars on the wifi signal when I go to sync it up to the internet, this still confuses me.

I've also considered any environmental aspects, to see if anything might be having an effect on the gamepad's reception, but I still don't think there's anything to cause any of this and this is why i'm really confused, is it a fault of the gamepad or console, or does it have something to do my house. Please can someone help me? If you think you know what the problem is please let me know ASAP.

seems to me like it can only be a faulty pad. As long as there is no walls in between the gamepad and the console it should work up to about 60 feet (i think).

Either there's something screwing up the signal for some weird reason or you might have yourself a faulty GamePad or console.
If possible, I'd recommend setting it up in a different room (or even house if possible), playing in there and seeing if you still have the problems.
Always good to try to eliminate as many possibilities if you can.
Besides that, I guess all you can really do is give Nintendo a call.

Oh, and the range from your WiFi router shouldn't be causing you any issues.
At my Mum's house where I'm currently staying, my Wii U is on the other side of the house to the router and I always have a really weak signal which disconnects all the time, but that doesn't have any impact on my GamePad (which is to be expected, as the connection between the console and GamePad has nothing to do with the Internet).