Need help: ballast replacement

[Chriskm3]

hey guys. a quick question to pick your brains.
Passager side hid headlight went out. I removed the both lights, used the working drivers side light to troubleshoot problem. Bulbs fine, found the problem in the ballast. Removed the working ballast from left, installed in the the right (not working) headlight and it worked fine. Great: problem solved. So I thought. I tried the broken ballast in the drivers side headlight just to be sure. No light.
Here is the dilema. I replaced the ballast with oem ballast of same part number.
I plugged the passager side headlight in at the passager side and the hid does not fire up. all other lights work fine. When i connect The same headlight to drivers side plug the lights fires up and hid works fine.
Do i need a computer reset???