TDI Headlights

I've noticed that my 2005 TDI headlights are just not as effective as they used to be. I have been thinking about replacing the entire assembly, but thought I would try installing Osram Nightbreaker Plus bulbs before I would do that. The problem I'm having is that I cannot find any info as to bulb model compatibility for my year and model. Does anyone have any info on this? Thanks!

If your Jetta is the MK5 chassis, from 2005.5 and up, it uses "H7" bulbs in the headlights.

If it's the MK4 chassis, from 1999.5 - 2005, it uses "9007" bulbs instead.

Mk4/mk5

Thanks for the info. After checking the sticker on the door post, I found the date of manufacture was August of '04. From what you wrote, it would apparently use "9007" bulbs.

Old bulbs generally are a bit dimmer but if the new ones don’t make you happy you may want to check the wiring voltage drop before looking at new assemblies. Issues with grounds or corroded connections are always possible and IMHO more likely than anything internal to the headlight. Also much cheaper to fix.

There is almost no reason to replace the entire headlight, unless you are upgrading to a different style unit. For a MkIV Jetta (with typically bad output in NA), replace the lenses if they are faded, fix the wiring if it's bad, or upgrade the bulbs if the lenses are clear. The stock units aren't great, but there are several options for improvement.

There are some YouTube videos about Halogen Headlights and their performance. It was interesting to see some companies with expensive bulbs that fade in a matter or weeks. Price and quality do not necessarily hold hands.

As for changing out the head light assembly, we have been reconditioning them for years. Practice makes perfect, or at least a heck of a lot better. sand the haze and yellow off starting with paper as low as 250 grit (depending on condition of lens), going to 1000 wet/ dry paper. Clean and dry. We use a Rustoleum product that is UV and yellowing resistant and it works for quite a long time. If the headlamp needs touched up, it's minutes to do.

Here is the product we buy at WalMart...
https://www.walmart.com/ip/Rust-Ole...Ultra-Cover-Clear-Finish-Spray-Paint/21078994

https://youtu.be/A_yd1bbXswM

I did this one day at work on a 15 minute break.
I used the 3m kit without the sandpaper and the mothers wheel polish and a battry operated drill. Video says 3 minutes. Add 1 minute because the drill is a little slower and not as big. No masking required. If you splatter just polish what ever you splatered. Lift hood to cut down on surface area.


I was not late coming back from break.

That video reminds me of the guys selling 'magic products' that work miracles. They get the Magic Wand that spray off dirt that would just about fall off if you blew on it. That lens wasn't very bad to begin with. It's been splattered for 'impressions sake'.

The bigger point, even if the headlight were hazed, without coating the plastic with a coating that keeps the plastic from oxidizing, it will look hazed in a matter of weeks.

I second Frank’s method. Worked fine on my 2000 for several years. I used an automotive clear coat from Canadian Tire for the topcoat.