Bluetooth Module (HC-05) LED Not Blinking, Unable to Connect to Phone

I am currently working on a Mars Rover project, and I am facing issues with the Bluetooth module (HC-05) while trying to establish a wireless connection with my phone. The problem is that the HC-05 module's LED is not blinking, and my phone is unable to detect it.
Despite various attempts and troubleshooting steps, I have been unable to resolve the issue. I've watched multiple YouTube videos, and a common suggestion is to connect the Arduino USB and press the reset button on the HC-05 module simultaneously for the LED to blink. However, this hasn't worked for me.
link to tutorial I'm following for making the rover: https://youtu.be/2Wq0nfoDsFs?si=7Y-rn4S5kcW7r9eq
code :
`int val;

int nb;

void setup() {

// put your setup code here, to run once:

Serial.begin(9600);

pinMode(9,OUTPUT);

pinMode(8,OUTPUT);

pinMode(7,OUTPUT);

pinMode(6,INPUT);

}

// put your main code here, to run repeatedly:

void loop()

{

if(Serial.available()>0)

{

int data= Serial.read();

Stop();

if(data=='R')

{

digitalWrite(9,HIGH);

digitalWrite(8,LOW);

digitalWrite(6,HIGH);

digitalWrite(7,LOW);

}

else if(data=='L')

{

digitalWrite(9,LOW);

digitalWrite(8,HIGH);

digitalWrite(6,LOW);

digitalWrite(7,HIGH);

}else if(data=='F'){

digitalWrite(9,LOW);

digitalWrite(8,HIGH);

digitalWrite(6,HIGH);

digitalWrite(7,LOW);

}else if(data=='B'){

digitalWrite(9,HIGH);

digitalWrite(8,LOW);

digitalWrite(6,LOW);

digitalWrite(7,HIGH);

}

}

}

void Stop()

{

digitalWrite(9,LOW);

digitalWrite(8,LOW);

digitalWrite(6,LOW);

digitalWrite(7,LOW);

}
`
Please help i have tried everything and nothing works :frowning:

And it never will. That procedure is for putting Bluetooth into AT mode, thereby preventing it from communicating with the phone.

To get the LED blinking, all you need is 5v applied to VCC and ground. If you can't get that, I guess it can only be down to

  1. 5v not being where you think it is.
  2. Bluetooth is defective.

Note the if you succeeded in putting it into AT mode you still get a flashing LED - a slow one.

Thank you for your prompt response! I've successfully established a Bluetooth connection between my phone and the rover using the app you recommended. However, I'm encountering a challenge where the rover doesn't respond to commands from the app.I have verified that all the connections are correct, and the Bluetooth module is successfully paired with my phone. Despite clicking the control buttons in the app, there is no movement from the rover. please help

But apparently not yet verified which thread you are on. I didn't recommend any app, and I haven't the faintest idea of what you are talking about. I guess you are talking about a Bluetooth terminal, so that should be a start.

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.