So I was trying to set up the LCD screen that came with my Genuino starter kit when I noticed that the board screen did not power on at all, unlike a few days ago when it worked.
In order to verify that the UNO was delivering power I simply connected an LED in series with a 220Ω resistor, between the 5V and ground pins. The LED did not power on.
I then, with the UNO still connected over USB, measured the voltage between across the resistor and LED and found it to be around 0.2-0.3V. Going further, reading the voltage between the 5V and ground solder connections on the back of the board and the reading is about the same.
I can power the LED from a digital pin that I set to HIGH, the issue seems to just be with the 5V pin.
Is there anything simple that I am missing (I hope there is) or is there likely a problem with my board? If there is a problem, could I use a digital pin to power a larger circuit such as that with an LCD or would the current supplied be too low?