If its anything like my old mondeo, an aftermarket HID kit was a nightmare on it. When they first switch on, they pull a lot of current, which was far too much for the original wiring to handle. They used to flicker like mad when powering up, and sometimes it used to make the abs warning light come on on the dash, presumeably the 'back EMF' was playing silly buggars with the ecu!

The only way round it was to fit relays and wire them in straight from the battery, then switch the relay from the positive feed from the headlamp switch. It took a lot of buggering about to get them working properly!

Not long after I got them all working, I junked them and stuck with standard uprated halogen bulbs, far easier!