This project is a very basic Traffic Light built from 3 LED's, Red, Yellow and Green. It is connected with 3 resistors to Gnd and 5v to an Arduino UNO. This project is a great build for beginners learning how to use Arduino and the the Arduino IDE programming language.


(1) Arduino UNO

(1) breadboard

(1) USB to Arduino cable

(1) laptop or computer

(3) LED's

- Red

- Yellow

- Green

(3) 220 ohm resistors

(3) Jumper Wires

(1) wire connected to GND

(1) wire connected to 5V



Connect the long leg of each LED to a jumper wire and pin.

I connected the red LED to pin 2, the yellow LED to pin 8 and the green LED to pin 12.

Conect the short leg of each LED to a resistor. Plug the other leg of the resistor into the the gnd column on the breadboard and connect the GND wire to that column. Connect the red 5V wire to the row in which each jumper wire connects to the long leg of the LED's.

Download the arduino code and the LED's will start to blink.

The red LED will blink for 5 seconds.

The green LED will blink for 5 seconds.

The yellow LED will blink for 2 seconds.

Just like in a real traffic light.