CSD U6L16 - LEDs not lighting up

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I expect the LED to turn on when I run the program, but nothing happens. I tried connecting to different ports on the circuit board.

Here’s photos of my setup. My board is a bit different since the ports are labeled #12, #6, etc. instead of A0, A1, etc.

Do I have the connections right? What else should I try?


Hi @agrant,

I don’t see your code. The link just goes to code.org home page.

One thing I am seeing in the pictures you provided is that the alligator clamps may not actually be connected to the negative and positive part of the LED sequins. Take a look at this page. The animated gif shows that the clamps need to be touching the metal part of the LED. The black pieces can actually be removed.

If this doesn’t help, you can post your code with the shared link and we’ll take a closer look.

Good luck!

This is actually on the first level of unit 6, lesson 16, which is the setup level, so there is no code shown. It just tells me to connect to the board, hit run, and then the led is supplied to light up. It tied connecting to the led a bunch of different ways but no luck. Is there something else I can do to test it?

Hmmm…here are some thoughts on troubleshooting:

  • Some of the data pins are reserved for special functions on the board, so when creating your own circuits, make sure to only use the following pins:
    • With a Circuit Playground Express board, only use pins “A6”, “A5”, “A4”, “A0”, or “A1”
    • With a Circuit Playground Classic board, only use pins 0, 2, 3, 6, and 12.
  • Make sure your sequin led is pulled apart from the others so you can accurately clip to the positive and negative ends - see picture below.
  • Try another board if you have one.
  • Try different sequin LEDs.

If anyone else has some tips - hopefully they can reply as well.