Beginner - Need Help - LED Light wont turn off

Completely new to coding and anything circuit related, and I'd appreciate some assistance. I just got my starter kit 2 days ago. I downloaded the IDE software, plugged in the UNO to my usb port, and the "L" LED light immediately started blinking.

I've been on some other websites where I was told to check the Ports in my device manager and in the IDE window itself. That all seems to be fine.

But this is making it so that I cant do the basic beginner projects, such as pushing a button to turn on an LED light, since my light is ALWAYS on or blinking. I uploaded the BareMinimum example sketch and it went from blinking to solid light.

Also, when attempting the pushbutton LED tutorial, I opened and uploaded the DigitalReadSerial example, and the LED light was constantly ON. Going through the steps and wiring up the breadboard, I opened the Serial Monitor to show that it was seeing 0's when the button wasnt pressed, and 1's when the button was pressed. It seems like the code and everything is being read properly, but obviously the light should go off and on when I push the button.

Also, when I unplugged the UNO and plugged it back in, it started blinking again.

Does anyone know a solution, or did I get a defective UNO board?

snipes0009: ..did I get a defective UNO board?

I don't think there is anything wrong with the board. The L LED may be on sometimes, and off other times, or blinking. It depends on what you have the code you upload DO. It is not used for every project, so unless the project you are doing does something with pin 13, which is where the LED is connected, you can just ignore what the L LED is doing.

But even if I upload the BareMinimum sketch from the examples library, it still stays on. There should be nothing in that code to tell the light to be on. Even the DigitalSerialRead sketch from the examples library, the light stays on. How will I know if the code and/or the push button is working if the LED light is always on? It should be off until I hit the button, correct?

snipes0009: There should be nothing in that code to tell the light to be on.

There is also nothing in that code to tell the light to be off.

If you are interested in the L LED to be off, you need to upload a program that sets pinMode of pin 13 to OUTPUT, then sets pin 13 LOW. That will make the LED off and stay off. For example, you could add this to the setup section of the BareMinimum sketch:

pinMode(13, OUTPUT);
digitalWrite(13, LOW);

When you don't have any code loaded that does something with that pin, the pin floats and could go high or low or somewhere in between which would be undefined. You will probably find if you touch the pin with your finger, or even come close to it with your finger while the pin is floating, it will have an affect on the LED. Google "Arduino floating pins" to learn more about that stuff.