VW Jetta Lights

[robinhood]

Hey All,

I am looking for some brighter lights for my Jetta. I have E-Code houseings currently with H4's the lows are not the best, the High's are acceptable. I do a lot of driving on twisty mountian roads and really need some more light up front. anyone have a suggest for a Bright H4?

2000 Jetta Tdi
Stock wiring
Hella housings.

 

[Lightdoctor]

First: install Osram Hyper Rallye 70/65W +50 H4 Bi-lux or Philips Xreme Power 60/55W H4 +80

Second: install a relayed harness kit using min. #14AWG wire.

 

[-Virgil-]

What year Jetta? And what E-code housings, specifically? Who manufactured them, did you buy them new or used, and what (specific) bulbs are in them now? How did you wire them into the US-market Jetta's headlamp circuit?

 

[robinhood]

I have a 2000 Jetta TDI.
I bought the E-Codes new, they are OEM Hella Housings.
I am just using the bulbs that came with the housings, on the stock wiring harness.

 

[-Virgil-]

Then I agree with Lightddoctor's recommendations. Make sure the lamps are aimed correctly, use the "VOL" specifications.

 

[robinhood]

anyone have some directions or weblinks for building a Relay?

 

[Alaric Darconville]

Daniel Stern does.

 

[robinhood]

Thanks for the Link!

 

[Lightdoctor]

anyone have some directions or weblinks for building a Relay?

Headlightsolutions.com has high quality custom made harnesses and also the bulbs mentioned above. (I bought a harness from them.) Also rallyelights.com (Susquehanna) can make one for you. Dan Stern only sends you the parts...you have to build it yourself. You also need to find out if your lights are power or ground switched.

 

[Alaric Darconville]

The Jetta should be power-switched, not ground-switched, but one could always test to be sure (your friendly* neighborhood VW mechanic should be able to tell you if it is or not, as well).

Lightdoctor: Isn't it "Headlight Services", rather than "Headlight Solutions"?

*Well, not only friendly, but qualified.

 

[Lightdoctor]

The Jetta should be power-switched, not ground-switched, but one could always test to be sure (your friendly* neighborhood VW mechanic should be able to tell you if it is or not, as well).

Lightdoctor: Isn't it "Headlight Services", rather than "Headlight Solutions"?

*Well, not only friendly, but qualified.

Oops, you're right. My bad. (You would think that I'd get it right being that I'm a customer of theirs.)

 

[Thawley]

Great thread. Google search for this exact question lead me here.

Thanks for the help guys.

 

[robinhood]

looks like a few people are making relays

http://www.headlightservices.com/
http://suvlights.com/product_info.php?products_id=112
www.easternbeaver.com
rallyelights.com (Susquehanna)

 

[Lightdoctor]

looks like a few people are making relays

http://www.headlightservices.com/
http://suvlights.com/product_info.php?products_id=112
www.easternbeaver.com
rallyelights.com (Susquehanna)

Suvlights.com harness products are of inferior quality when compared to the other choices.

 

[robinhood]

I took a few measurements today. I am getting 14.4V at the battery and 13.1V at the headlight. with the engine and headlights on. will 1.2V make that big of a difference?

 

[Alaric Darconville]

I took a few measurements today. I am getting 14.4V at the battery and 13.1V at the headlight. with the engine and headlights on. will 1.2V make that big of a difference?

Measuring the output across the bulb terminals isn't giving the full story. Be sure to test it using the method described at the link in Post #7

While 13.1V is above the 12.8V used as the test point in the US, you can stand to get higher, as well... 14.4V at the bulbs, however, would be a little *too* high, drastically shortening the life.

 

[Qship1996]

13.1 volts at idle seems pretty good- have somebody get in car and raise RPMs to typical highway speed and see where that voltage number goes, if it gets much higher than 13.4-13.6 I would NOT add a harness, as you will be replacing bulbs much more frequently than needed.

 

[Alaric Darconville]

13.1 volts at idle seems pretty good

We still don't know if that's just a measurement across the terminals at the bulb, or if it was calculated by getting the voltage drop at each leg. Until we know the reading was taken correctly, we can't advise on whether or not to add relays.

 

[robinhood]

Ok after further testing looks like I have a voltage drop of 1.5V.
I followed the instructions on the DS site for measuring the voltages.

 

[-Virgil-]

Measuring across the (hooked up and operating) bulb terminals tells you the voltage reaching the bulbs. Measuring the way Stern says to (across each leg of the circuit) tells you the voltage reaching the bulbs and whether the loss is in the feed or the ground leg or both.

Do you need a harness? If you intend to upgrade the bulb wattage, then yes. If not, then it depends on your priorities. With voltage change, bulb life changes exponentially (power -13, that is negative 13) and bulb output changes exponentially (power 3.4, that is positive 3.4). So life effects are much more pronounced than output effects, but it's also a hell of a lot less expensive and difficult to replace headlight bulbs than to replace bent sheetmetal and broken bones.