CAN-BUS Shield V1.2 with arduino mega

Hi all.
I use CAN-BUS Shield V1.2 with arduino mega 2560.
If i give power to arduino to usb connector, all works fine but if i try to give the same 5v power to arduino to JACK DC connector the comunication between shield and mega not work. Any ideea please?
Thanks in advance.

@tao13, your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with your project :wink: See About the Installation & Troubleshooting category.

The minimum requirement for the barrel jack is 7V (absolute minimu 6V) , not 5V.

If you want to power the board with 5V, use a cell phone charger and USB or connect the 5V to the 5V pin. In the latter case, you have to disconnect it before connecting to a PC using USB.

Thanks. I 'll try this