Arduino power led not turning on

hello, I am quite a beginner when using arduino we just started studying this a few months ago. Earlier when I was plugging my arduino uno in my laptop using a usb cable the laptop doesn’t recognize it and the led indicators doesn’t turn on. What does this mean??

Update: It started working again, I think I just let it rest for the whole night and turned off my laptop. Thanks for all your help.

The Uno has one power led at one side and 3 leds at the other side? The power led should switch on; if that doesn’t happen, either your cable is broken or is not properly plugged (check both sides) in or your PC is refusing to power it due to overload.

If the power led is on, you might have a situation where the cable is not completely plugged in; make sure both sides are properly plugged in.

The L led should flash a few times in quick succession after power is applied; after that it’s controlled by the software that you have loaded in the board.

It means the Arduino is dead, the USB cable is dead, or the USB port on the laptop is turned off. The laptop will turn off the port if a USB device (like the Arduino) tries to draw too much power, like if there is a short circuit between +5V and Gnd. Unplugging the USB device will probably reset it.

Do you have a different USB device you can plug in to see if it can get power from the port? If that fails, try re-starting the laptop.

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