The LED is burnt out on your Dye Rotor?
Same thing happened on my rotor. After trying to search for tutorials on what size SMD leds to replace on the internet, I found basically none.
Perfect reason to try and modify mine! Instead of using an SMD led which requires a bit more soldering skills, I chose the 3mm LED which are bigger and easier for any beginner to solder. Hopefully this will help many of you out there who either has a burnt out LED on the rotor OR would like to spice things up with their setup and match their color kit.
Here's an example of my LED work from a few years ago... I told you it's been a while!!!