Introduction
In this tutorial, we will learn about the KY-011 module, what is a 2-color LED and we will build a simple 2-color blinker using an Arduino and the KY-011 module.
2 Colour LED Module KY-011
The KY-011 Module will be our main component for this tutorial. This module has a 2-color LED mounted on a breakout board. Figure 1 shows the module as seen in fritzing.

Pinout
The KY-011 module has three pins.
Component Pin | Arduino Uno board Pin |
---|---|
(-) | Green |
middle | Red |
S | GND |
What is a 2 Colour LED?
A 2-color LED is simply two different colored LED’s assembled in one package. The color of each LED is Red, and Green.
Project - Arduino 2 Colour Blinker
After learning about the KY-011 module and the 2-colour LED, it is now time to build a project using the module. Our project will alternate the color (red/green) of the LED every one-second.
Components
For this project, we need the following components:
- Arduino Uno board (1 pc.)
- KY-011 2 Colour LED Module (1 pc.)
- 220-ohm resistor (2 pcs.)
- Breadboard (1 pc.)
- Jumper wires
Wiring Diagram

Figure 2 shows the connection between the Arduino Uno and the KY-011 2 Colour LED Module. The two 220-ohm resistors are needed between the Arduino and the Green and Red pins of the KY-011 to protect the LED from over-current.
The KY-011 module pins are connected to the Arduino Uno board as follows:
Component Pin | Resistor | Arduino Uno board Pin |
---|---|---|
(-) | 220 Ohms | 9 |
middle | 220 Ohms | 8 |
S | - | GND |
The Code
Below is the Arduino sketch for our project. I have added comments to explain important parts of the code. Save the code as KY-011.ino and upload it to your Arduino board.
// Arduino and KY-011 module
void setup() {
pinMode(8, OUTPUT); // module's red pin
pinMode(9, OUTPUT); // module's green pin
digitalWrite(8, LOW); // switch off red
digitalWrite(9, LOW);
}
void loop() {
digitalWrite(8, HIGH); // switch on red
delay(1000); // wait 1 second
digitalWrite(8, LOW); // switch off red
digitalWrite(9, HIGH); // switch on green
delay(1000); // wait 1 second
digitalWrite(9, LOW); // switch off green
}
Project Test
Apply power to your Arduino Uno board. The KY-011 should alternate color every one-second.