DIY Outdoor Monitor Kit LED Control

Hi all.

I have purchased and assembled a DIY Outdoor Monitor Kit and the device is working great, thanks!

Does anyone know if it is possible to control/turn off the blue LED on the device? I’ve been testing the device indoors and it would be great if I could turn off the LED at night as it is quite bright.

I’ve tried setting the LED Configuration to LEDs off for this location in the AirGradient Dashboard however it doesn’t seem to have any effect.


I did some more digging and ended up having to upload a custom firmware that didn’t turn the led on.

Steps for anyone else that wants to do it:

  1. Follow the steps starting at the Flashing With The Arduino Software section here
  2. Patch the PMS Library as per the link in the previous step
  3. Edit the DIY_OUTDOOR_C3.ino file and comment out the switchLED(true); and switchLED(false); lines in the sendPayload function as per the below code.
  4. Hold down the button on the device and plug it in to your laptop/PC. Release the button after it is connected.
  5. Select the COM port that shows up in Tools > Port
  6. Click the Upload button
void sendPayload(String payload) {
      if(WiFi.status()== WL_CONNECTED){
      String url = APIROOT + "sensors/airgradient:" + getNormalizedMac() + "/measures";
      client.setConnectTimeout(5 * 1000);
      client.addHeader("content-type", "application/json");
      int httpCode = client.POST(payload);
    else {
      debug("post skipped, not network connection");