IR Sensor Arduino — Wiring, Code & Proteus Simulation

IR Sensor Arduino projects are one of the fastest ways to add obstacle and motion detection to an Arduino Uno build. In this guide we wire an IR sensor module to Arduino, load the IR sensor Arduino code, and test it in a Proteus simulation — so you can move straight from breadboard to real projects like counters, parking systems and line followers.

Welcome to this beginner-friendly Arduino tutorial on the ir. By the end of the guide, you'll wire the module to an Arduino UNO, flash a short sketch, and read live values on the Serial Monitor — no prior electronics experience required.

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What you'll learn

• How the module works in plain language
• The exact parts you need and how to wire them safely
• The full Arduino IDE sketch with comments
• Common issues and how to fix them

Arduino code

Open the Arduino IDE, paste the sketch below into a new file, install any libraries the sketch #includes (Tools → Manage Libraries), select your board and COM port, then click Upload.

int IRSensor = 9; // connect ir sensor module to Arduino pin 9
int LED = 13; // conect LED to Arduino pin 13


void setup()
{
  Serial.begin(115200); // Init Serila at 115200 Baud
  Serial.println("Serial Working"); // Test to check if serial is working or not
  pinMode(IRSensor, INPUT); // IR Sensor pin INPUT
  pinMode(LED, OUTPUT); // LED Pin Output
}

void loop()
{
  int sensorStatus = digitalRead(IRSensor); // Set the GPIO as Input

  if (sensorStatus == 1) // Check if the pin high or not
  {
    // if the pin is high turn off the onboard Led 
    digitalWrite(LED, LOW); // LED LOW
    Serial.println("Motion Ended!"); // print Motion Detected! on the serial monitor window 
  }
  else
  {
    //else turn on the onboard LED
    digitalWrite(LED, HIGH); // LED High
    Serial.println("Motion Detected!"); // print Motion Ended! on the serial monitor window 
  }
}

How it works

The sketch initialises serial communication and the ir driver in setup(), then in loop() it samples the sensor at a regular interval and prints the result to the Serial Monitor at 9600 baud. Open the Serial Monitor (Ctrl+Shift+M) after upload to see live readings.

Troubleshooting checklist

• No readings: verify the baud rate in Serial Monitor matches the sketch (usually 9600).
• Garbage characters: wrong baud rate or loose GND wire.
• Library not found: install the exact library referenced in the #include line via Library Manager.
• Sensor not detected (I²C): run an I²C scanner sketch to confirm the address.

What to build next

Once the basic readout works, try logging values to an SD card, sending them over Wi-Fi with an ESP32, or pushing them to a Blynk IoT dashboard. Pair this module with our simulator round-up to prototype the circuit before soldering.

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