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2-Way Traffic Light System using Arduino

Updated: Mar 15

In this project, we design a 2-way traffic light controller system using Arduino . In this system, we will arrange the LED lights to glow in a systematic order to control traffic.

Table Of Contents :

Hardware requirements:

Arduino UNO:

Arduino UNO
Arduino UNO

The Arduino is a programmable #microcontroller, it's an open-source electronics proto-type platform. It interacts with the user by receiving input with the aid of sensors and provides the output employing LED, buzzer, etc.,

In order to know more about the Arduino UNO, refer to this article.



LED is a semiconductor light source that emits light when a current passes through it. Electrons in the semiconductor combine with holes by passing through the gap which inturns release energy in the form of photons. In this project, we use 6 LEDs (Red, Green, Yellow).



Resistor as the name signifies, opposes the flow of electrons. The Resistor is a passive element and has two terminals. They are basically used to monitor the current flow and also as voltage dividers. The #resistor that we would use in this circuit is a 1 k-ohm resistor and the color code for this resistor is Brown, Black, Red and Gold.

Connecting wires:

Connecting wires
Connecting wires

Connecting wires are used to establish connections between different components in the circuit.

Software requirements:

Arduino IDE:

Arduino IDE-logo
Arduino IDE-logo

The Arduino IDE (Integrated Development Environment) is a cross-platform application (for Windows, macOS, Linux) that is written in functions from C and C++. It is used to write and upload programs to Arduino compatible boards, but also, with the help of third-party cores, other vendor development boards.

Circuit connection:

Circuit connection involves the following steps:

  • The negative terminals of the two sets of LED's are connected to the ground pin of the Arduino through a 1 k-ohm resistor.

  • The positive terminals of the 6 LED's are connected to digital pins 1-6 of the Arduino.

Code explanation:


The Arduino is loaded with the code and executed. We can observe that if green LED glows in a set then in other set, red LED glows and vice-versa. Yellow LED glows in both sets simultaneously.

Video By - Amber Bhattacharya and Neha Patil

Traffic Signal Drawings and Images:

To better understand traffic signal arrangements, refer to various traffic signal drawings commonly used in traffic engineering. These drawings showcase the layout and positioning of traffic signals at different intersections.

Additionally, observe traffic signal images showcasing the different colors (green, yellow, and red) and their meanings. The green light signals "go" or "proceed," the yellow light serves as a warning, indicating the light will change to red, and the red light indicates "stop."

Traffic Signs in India:

In India, traffic signs play a pivotal role in regulating vehicular flow and ensuring road safety. Familiarize yourself with common traffic signs such as Stop signs, No Entry signs, and Pedestrian Crossing signs. Understanding these signs is vital for maintaining road discipline and preventing accidents.


By successfully constructing the 2-way traffic light controller using the Arduino UNO microcontroller, you have honed your Arduino programming skills while gaining practical insights into traffic signal operations. Exploring traffic signal drawings and traffic signal images, along with understanding traffic signs in India, emphasizes the importance of efficient traffic management and road safety practices.


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Content Written by-

Name - Kiranmai Chigurupati

Portfolio Link - click here

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LearnElectronics India's explanation is spot-on. Great work!


Anushka Gupta
Anushka Gupta
Jul 20, 2023

Wow, what an amazing tutorial! The 2-way traffic light system blog by Learn Electronics India is a true treasure trove of knowledge. The way the author broke down complex concepts into simple terms is commendable. I thoroughly enjoyed working on this project, and the blog made it possible. Thank you for making learning electronics exciting and engaging.

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