Weird HID Issue

This issue has me stumped. I purchased an HID kit and replaced a single halogen bulb with one ballast/bulb combo (couldn't do both because the other halogen bulb is currently stuck in the housing). The HID bulb worked great compared to the halogen bulb however after two months it stopped working (ballast went bad). I swapped the ballast out with a brand new one and the bulb still wouldn't light up. So, I tested the bulb/ballast combo directly up to a 12v and it lit up no problem. I checked the fuses for the low beams and they all look fine. I ended up putting a halogen bulb back into the original harness and the bulb lit up, officially leaving me stumped. Anyone have any suggestions?