I'm a new to all things electronics and I'm having trouble using a DFRobot Bluno V2 with a DFRobot Relay Shield for Arduino V2.1. For testing purposes I've done the exact same circuit as represented in this diagram:


But it is not working. If I send HIGH signal to D10 or press the S4 button on the shield, the circuit does not close and the LED doesn't turn on (even though the LED4 next to the relay on the shield lights up). If I do same circuit connecting the LED to D10 directly (ie., without using the relay) it works fine. I've also tested this with the other relays on the shield and the results were the same.

Does anyone know what might be the issue? What am I doing wrong?

Thanks in advance.

  • I do not know much about these boards as well, but did you try powering the board through the Vin pin?
    – user11325
    Commented Jul 21, 2015 at 9:47
  • Could you try using a wire directly connect PIN10 with 5V? then try it with GND. if you hear a sound like "Te" that means the relay board is work fine. the problem is from your arduino board or code.
    – user14880
    Commented Nov 17, 2015 at 5:40


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