I have a 07 IS350 and my passenger side headlight needs a new ballast. I changed both headlight bulbs and the R/F low beam still doesn’t work. The R/F headlight cover also has some condensation inside which may have been a contributing factor in the headlight no longer working.

When changing both D4S bulbs, I had to remove the airbox to access the low beam cover. I happened to look at the high beam cover and found the two prongs holding it in had come loose, so that could have contributed to the condensation getting into the headlight unit.

I also checked the wire meshed cable connector that connects to the low beam headlight and it appears to have a “brownish” color down the middle. That cable is part of the ballast which I’m thinking is bad. I checked the fuse for both low beam headlights, they were both good.

Still attempting to get condensation out by hairdryer & vacuum, and most of it is gone however, the next day the condensation is back.
A new headlight ballast can be had for around $40-$50 + labor vs replacing the headlight unit.

I would appreciate feedback on both options.
Thanks & looking forward to your responses!

( By the way where are the “vents” on the rear of the headlight unit, couldn’t find them on mine)

 

If I could fix the condensation problem, I would just replace the ballast. The labor for both is about the same -- mainly taking out the headlights, which isn't too difficult.

 

Thanks for reaffirming my thinking on this. On the condensation issue, I tried drying it out with a blower/ dryer and most of the condensation dried up however, the next day it was back.

Most of the condensation seems to be accumulating at the top rear of the headlight unit. I read these units have “ vents” at the rear of the headlight unit in that upper rear/ back area closest to the fender, in this case the passenger side. I went out today and upon my return home, the moisture was in that area and it felt pretty warm to the touch. The driver side headlamp was not warm at all.

Would you happen to know if that vent location is correct because, I couldn’t locate vents in that area. Maybe I didn’t know what to look for or the location. They say these vents can get clogged, so if I knew where they were I could check them make sure they aren’t clogged with some type of debris.

Thanks for the advice, and I hope you can help me on the vent location.

 

I had taken the headlights off and baked it opened before, but I don't recall seeing any vents. If they're there, they're probably not that big or obvious.

If the high beam covers are properly sealed (maybe clean out any dirt or dust on the cover if any), then the only thing to do might be to take the headlight out and check for vents or replace.

 

I spoke with someone here that had this same issue. He referred me to his guy and since I will be providing the ballast, which will run me around $35-$40 from Ebay, I'll just pay him the labor cost. I saw his finished car and it came out great. He also had his guy seal his headlight plastic cover for a leak which caused the condensation.

I want to thank you for helping me make the correct decision because checking Ebay costs for used headlamp units, they all run $300-$400 for a decent one and adding labor would exceed the first option. At least this way, I know the ballast is new vs possibly having to change out the ballast in the replacement unit if I went that route.

Thanks again for the advice!