I purchased a used CM Quickfire Rapid-i off of ebay awhile back. It was being sold for cheap because it had two LEDs out on it, but apart from that it was fully working.
I de-soldered all of the stock LEDs from the board and replaced them with 2x3x4mm "20MA" rated LEDs in Orange (Rated Voltage: 2 - 2.4v) and Yellow (2 - 2.2v). At various times during the process of re-soldering the new LEDs I plugged in the keyboard to ensure that everything was working. Though the board worked fine, the LEDs would never turn completely off, and they'd get brighter when I hit the "brightness down" toggle, and dimmer with the "brightness up" toggle. I assumed that I just needed to add all of the LEDs for everything to work correctly, so I kept going.
Once all of the new LEDs were on the board I plugged it in to my computer to find that the LEDs lit up but no key presses were registering. Even the built-in macros to adjust the brightness of the LEDs etc. were not working. The board itself seems to be alive though - it registers as a "Quickfire Rapid-i" on every computer that I plug it into, and I was even able to update the firmware using CM's firmware updating tool.
I closely inspected the pcb and everything looks fine with no shorts etc. I've soldered boards before to do switch swaps and never had an issue. However, this is the first time that I've totally replaced the LEDs on a backlit board.
Any thoughts on what I did wrong, or what I can do to solve the problem? Thanks!
