Introduction: Bluetooth Controlled Led Using Arduino and HC-05

About: I am passionate about electronics and DIY is the best way to learn and implement them.

In this instructable you are going to learn how to interface HC-05 bluetooth module and control leds using arduino over an android application.


1.arduino (any i am using uno r3)

2.hc-05 bluetooth module

3.leds and 100ohms resistor

4.jumper wires

5.arduino usb cable for programming


Step 2: CODING

I have attached the code please paste it in the IDE and select the right COM port and upload the code.The explanation of the code is given in comments in the code itself please read it.

Step 3: WIRING

Wire the components as shown in the diagram.


When uploading the code make sure the bluetooth module is disconnected or else it may malfunction.I havent added a resistor in series with led ,make sure u add it and use a 5v rated led


From the playstore download and install "Arduino bluetooth controller" by Giumig Apps .Make sure you have uploaded the code and the arduino is powered,you can see a red led blinking or glowing in the bluetooth module.Open the app and pair your bluetooth module and select terminal mode.

1.If you send "H" the led will be on sending other characters will make the led off.