Hey guys,

I’m having a real hard time here with my 2004 TL. The hid headlights went out last week and I’ve been doing everything I think might be wrong. Here’s a list of what I’ve done:
Changed the HID bulbs

Checked the fuses

Checked the relay

The ballast is fine too

Checked the DRL relay and it’s fine (even connected it to power and the DRL lights came on)
My car alarm had gone off last week before they went out so I thought the HID’s had died because they don’t like getting turned off and on a ton but I guess that is not the case.(As I changed the bulbs and it still didn’t fix the problem) When I was messing with the lights and turning them off and back on the passenger side light came on but then went back out.

So my conclusion is that the power supply to the HID lights is getting interrupted or messed up at some point, does anyone have a clue of what I should check or do next? I’ve had a real hard time trying to find how the wiring goes around the car and to the HID so if anyone has a diagram or anything of the route the wires take that’d be helpful as well.

 

How did you come to the conclusion that the “ballast is fine”

 

^ This.

You also need to account for the igniters which can also go bad.

If the bulbs/igniters/ballasts are indeed OK, the next step is to check for continuity on the wire harnesses feeding the ballasts.

 

I assumed the ballast was fine because the passenger side headlight came on once, but now I see that doesn't mean they're fine so I'll look into the ballast. Changed the bulbs with new ones so we know it's not that. I'll look into your suggestions. Thanks!

 

And in case it needs to be said... Don't go probing the ballasts. They can spit something like 40kV at you. Swap side to side if you suspect one is OK, or swap in replacements as you work through which components work and which ones don't.

 

 

Yes, I'm being careful thanks for the reminder. We pulled the front off and we are getting 12 volts into the ballast and none out, we get a bit of power for a millisecond and then it drops to 0. Our conclusion is that the ballast is shot, do you agree with that? Any suggestions on replacement if so? Thinking of doing LED maybe or something that hopefully won't get fried by the alarm in the future. Thanks for your help again!