0
\$\begingroup\$

I'm hoping for help troubleshooting a light array I built for my son's room. I strung together 8 strips of WS2811 addressable RGB LEDs (30 per strip). I soldered all the strings together, and tested them prior to mounting. Whole strand lit up beautifully. Then, I mounted them onto his desk, and now the first strip lights, and only the first LED of the second strand lights and that one LED is significantly dimmer.

No problem, I think, one of the connections just came loose. But it doesn't seem as though I have any bad solders, and jiggling the wires around doesn't really cause any change in the lone weak LED on the second strip.

  • I put a multimeter on the end of the first, well-behaved, strip. No value reading across +5V and Gnd. But no reading wouldn't explain how the second strip has one light with some small amount of juice.
  • I mounted onto the painted wood surface using the adhesive on the back of the strips, and the back does have the exposed copper pads. I figured that the paint on the wood would be sufficiently insulating, but could there be voltage drop from the mounting?
  • I'm running this with an ESP32, and have a dedicated 5V 2A power supply powering the LEDs.

I'm sure it's a bad solder, but without getting any reading from the good strip's +5V and GND, I'm a little confused. Also, there's clearly some current moving on since the second strip is lighting up a little bit. I'd like to troubleshoot it before I have to unmount the whole dang thing and redo the wiring.

Thanks!

\$\endgroup\$
0
\$\begingroup\$

Definitely a cold solder on the ground pad. Not sure why I got no reading on the multimeter, but whatever.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.