2002 Maxima, HID kit installed for the fogs. Well when my buddy (very mechanically inclined...unlike me) installed them the first time only one side worked. Well we switched the ballast box from the side that worked to the side that didn't and that side then worked.

We assumed I had a bad ballast box. Replaced that ballast box with a new one and nothing. He checked and it has 12 volts going to & from the box so we are stumped. For the hell of it we even swapped out the bulb with a new bulb and nothing.

Any thoughts?

 

reverse polarity / if relayed... make sure its grounded correctly

 

+1 an extremely common thing with HID's

 

You friend should have noticed the thin gauge of factory fog wiring and recommended you get a relay harness so you can get power and ground direct to the battery