Power and hard drive LED won't turn on

Question

I built a computer and everything worked fine. And then later on I decided to get a new case for it. After that the computer still turned on and worked fine, but when I turn it on the power LED and HDD LED won't turn on at all. What are some possible reasons for this and how can I fix it? (And yes, I made sure that I plugged the front panel cords in the motherboard correctly.)

Answer 1

LED lights have polarity. This means the + and - ends must go to the proper terminals. Try turning the connector around.

Answer 2

Well, there's the obvious, which you've already stated: Motherboard pinout compared to case connectors. These must match, and I've seen motherboards and cases where the labelling doesn't make the correct pinout clear.

Outside of that, there is ofcourse the possibility that the LEDs themselves are broken and won't light up. While this is unlikely, especially with a new case, it is a possibility, especially if connected incorrectly at one point.