Arduino Not Lighting Up LED

Good evening,

I cannot seem to get my Arduino to provide power again... I'm not sure if it is broken or I am doing something incredibly incorrect. I'm following the instruction directly from the site just to get an LED to turn on. The LED on the board does work correctly from my sketches, but I cannot seem to get any of the PWM digital pins to work. 


Post your sketch well formated and in code tags and the schematic.

post your schematic


The schematic says PIN 13, but I have also tried PINs 12, 2, 3, 4, 11 at this point... I've swapped out LEDs, resistors, jumper wires... no avail.


If you post your code as described in How to get the best out of this forum, more forum members will read it.

Do you have the LED oriented correctly?


connect all part as specified in your schematic.


Turns an LED on for one second, then off for one second, repeatedly.

Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
the correct LED pin independent of which board is used.
If you want to know what pin the on-board LED is connected to on your Arduino
model, check the Technical Specs of your board at:
Arduino - Products

modified 8 May 2014
by Scott Fitzgerald
modified 2 Sep 2016
by Arturo Guadalupi
modified 8 Sep 2016
by Colby Newman

This example code is in the public domain.

// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin LED_BUILTIN as an output.
pinMode(12, OUTPUT);


// the loop function runs over and over again forever
void loop() {
digitalWrite(12, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(12, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second

Just tried again and the LED is blinking on the Arduino, but not the LED attached to my breadboard

Unbelievable.... you win all points.

I apologize for wasting these minutes of your evening. I had the LED the wrong direction the whole time... Thank you for your assistance

1 Like

It happens to all of us at one time or another.

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