Wifi Shield suddenly stopped working (i2c included).. Not enough power?

Hello,

I have my arduino mega, 2560 (1) with the TFT attached powered by my phone charger (5V 1A) through USB port. (see attachment)

It has been working for days, but a few days ago, my other arduino 2, 1280 (with wifi shield) stopped working. The problem is in the Wifi Shield because when i unplug it, arduino2 works properly.

Even if i disconnect I2C communication and try to complile a program in arduino2 with wifi shield attached it doesn´t upload. (L9 doesn´t even blink)

What may the problem be?

Thanks, Antonio

Check your power supply voltage. If you're operating both the Arduino and the WiFi shield, and it works after you unplug the WiFi shield, perhaps your WiFi is dragging down your voltage. I've had arduinos, still loading code and functioning at 3.5 v., but I wouldn't recommend that.

But why did it work a week ago? Wasnt it supposed not to work at all since the beginning? And it worked well, uploaded the code perfectly, when programming only that arduino with wifi shield, separatelly from the other… can you check my attachment please? Can it be because of bad wiring?

And what is the recommended power supply voltage?

Many thanks!