couldn't you just post the question on hereCould someone read my question about my hps bulb under my profile
ahaha... i'm sure thats gonna help so much... lolmay god have mercy
That is a good point. It could even just be the actual switch that is broken. If it is not a switchable ballast then check where the bulb screws into the socket. (Unplug the light first!)There is a tab that sticks up that the bottom of the bulb has to make contact with in order to light up. Sometimes this tab is not sticking up enough to touch the bottom of the bulb. It can be easily bent up with a small screwdriver or needle-nose pliers. But that probably isn't your problem if the same socket lights up the MH bulb. Unless the bulbs are made differently.The only thing that I can think of is if it is a switchable ballast - there should be some kind of switch on it to change from MH to HPS ---
The HPS part of the ballast could be blown, I would exchange it for a new one if possible.
That's all I got