Troubleshooting¶

Quick diagnosis¶

Nothing lights up. Diode is almost certainly backwards, or the USB cable isn't plugged in. Check the band direction first (it must face the LEDs), then check the cable.

LEDs flicker or show wrong colors. Both USB cables aren't on the same dual-port power source. Fix that and retest. If the problem persists, measure V+ on the LED strip — it should read ~4.3V. If it reads ~5V, the diode is bypassed or shorted.

Some LEDs work, others are dark. Broken chain. The failure point is the joint right after the last working LED. Reflow the V+, GND, or DOUT-to-DIN connection there.

Red and green work but no blue, or LEDs dim after a while. Undervoltage. Measure V+ under load — if it's significantly below 4.3V, the diode or the USB power source is underspec'd. Try a known-good 1A+ USB source.

LEDs stay dark even though the Scion is powered. They have power but no data arriving. Either the DATA wire is broken, the Scion isn't powered, or the scraped trace isn't actually the data trace.

Further reading¶

• Adafruit NeoPixel Überguide — everything about NeoPixels
• Tips for Troubleshooting NeoPixel Glitches — the blog post that explains the voltage rule behind the diode
• Adafruit's Guide to Excellent Soldering — if you need to brush up before you start