Headlights come on then go off

I have HID's on H7, when i turn them on, they come on for about 2 secs then go off, i then have to pull the black HID wire off the H7 plug hold it on the end of the female lucar till it gets up to temperature then sliding it back into the lucar on the H7 and they stay on till i then turn my lights off again.

Does anyone know what it could be? I've crimped the lucar in incase it wasn't connecting very well but still the same.

Thanks,

Oli