[neonhomer]

On my 99 B5, I had to rebuild the wiring harnesses for the headlights, as they were pretty much cooked (no insulation on the wires. I don't know how they DIDN'T short out.)

So I noticed there are two bulbs in my headlights. A regular dual element that is the headlight, and then one to the side which looks like an H7 bulb.

I thought they might be DRL's, but I've read that most of the DRL's are just 194's... not a H7. Regardless, mine don't come on. I'd have to dig into the wiring to find out, but I'm pretty sure the 173 relay is there, and I have a regular headlight switch (no Euroswitch).

 

[Steve in Chicago]

There are three beam patterns that come from the B5 headlight fixtures. The three filaments create the three beam patterns. There is your regular low beam (your DRL's are that beam just powered at a lower voltage). Then there is your high beam. Then there is your fog lights.

If you pull the headlight switch out towards you one click, the fog light beam comes on. The fog beam pattern is wide and low directly in front of the car. Fogs and highs won't come on at the same time.

 

[neonhomer]

I don't think I have the right switch then. When all of my lights are off, my switch is at about the 11 o'clock position. Pulling out on the switch forces it to turn to the 12 o'clock position, turning the lights on.

I have a little indicator at around the 9 o'clock position that looks like it might be a DRL indicator. However, after looking, I don't think my DRL's work.

Edit - This is the switch I have now:

 

[Steve in Chicago]

The following is for the B5 headlights. When they came out with the B5.5 models, they redesigned the headlight system a bit.


You described normal operation for that style switch. The 11:00 position like shown in the photo is the OFF position. In the OFF position, your DRL's should come on when the key is on and the parking brake released. Turning the switch to the 12:00 position brings on all the parking lights and also brightens the headlights from DRL mode to full brightness headlight mode. If you pull out on the switch, the fogs will also come on and that little indicator at the 9:00 position should light up. That little symbol at 9:00 represents fog lights.

If you start with the switch in the OFF position and pull the switch out to light up the fogs, the switch also automatically moves one click to the right to bring on the parking lights and headlights. They don't want you driving around with just the fogs and no other lighting on.

Some of the switches pull out two clicks. The first pull is to turn on the front fog lights. The second pull turns on the rear fog light. They didn't install the rear fog light feature in the North American cars. You can add that modification yourself if you like.

The high beams come on via the left stalk on the steering column. The highs and the fogs won't come on at the same time. If you have your fogs on and you flash your high beams, the fogs will go out while the highs are on. The fogs will come back on when the high beams go out.

The DRL's and regular headlights come from the outer section of the headlight fixture. This is done with a single filament bulb run at two different voltages.

The fogs and the high beams come from the inner section of the headlight fixture. This is done with a dual filament bulb. The two filaments are positioned in two different focal points of the reflector. Each one creates a different beam pattern. If you've ever seen a flashlight where you can adjust the beam from pin-spot to wide-flood, you'll have seen how this sort of optics work.

 

[neonhomer]

Okay, well, what happens with mine is with the car running, and the parking brake off, and the switch off, I have no lights.

When I turn the switch to 12 o'clock, I get running lights.

When I pull the switch out at 12 o'clock, my headlights come on (low beam of dual element bulbs).

I have noticed that the fog lamp light does come on when pulling the switch out.

So, I am assuming the relays for the fog lamps are either bad or missing. I checked the fuses and they are good.

I am also assuming, that while the 173 relay is in the block, it is either bad or not working.

I noticed the other day that the wiring in the headlights themselves is toasted. I rebuilt one of the harnesses with new wire, and lucked into a pair of harnesses at the junkyard (aftermarket looks like). I rebuilt the driver's side light. I am going to do the passenger's side light soon. Then I guess it's from there to troubleshoot.

 

[Steve in Chicago]

It sounds like your regular headlights (DRL and low beam) are not working at all. You're driving around using your fog lights. Your nighttime lighting must be awful. Check the headlight fuses to see if they are good or not. Left and right have separate fuses. They might have both popped back when your wiring was all messed up. Your headlight switch might also be faulty.

The 173 relay is what switches the low beam headlight circuit between DRL and full bright. There is a resistor wire used to lower the voltage reaching the bulb for DRL mode. When the 173 relay switches over, the resistor wire is bypassed to deliver full voltage to the low beam bulbs.

 

[neonhomer]

The low beam of the dual element bulb (closest to the grille) is what comes on. When I flip the high beams on, the other element of the dual element bulb comes on, and the high beam light comes on in the IPC.

The outer bulb (farthest from the grille, a single element bulb) never comes on.

Will have to change that other harness, and then check the fuses and go from there.

 

[Steve in Chicago]

The low beam of the dual element bulb (closest to the grille) is what comes on.

That's your fog light.

The outer bulb (farthest from the grille, a single element bulb) never comes on.

That's your DRL and low beam.


A wiring diagram would come in handy for this sort of troubleshooting. Follow the circuit from beginning to end and see where the voltage drops out. The back section of the Bentley Manual has schematics.

 

[neonhomer]

Okay, I think I understand now.

So I need to fix the harnesses, and most likely my low beam fuses are popped.

Just went out and checked. One low beam fuse is blown. I'm not going to replace it until I replace the other harness.

 

[Steve in Chicago]

Lets hope it's just the fuses. If that's the case, once you get your rewire done, you'll be back in business.

I wonder what burnt up the original harness. Over-wattage bulbs are one way to do that. What amp fuse did you find in your headlight circuit?

 

[neonhomer]

The low beams were 10A fuses. One was blown, one was not.

 

[Steve in Chicago]

The low beams were 10A fuses.

That should be the correct size for your year. I think they went to 15A in later years with the same gauge wire in the harness. The 10 offers more protection then the 15.

 

[Urlik]

Reminds me of when I came home on mid tour and we had to drive the Passat out to Arizona right away. Well as night came out on I10 in West Texas I turn on the headlights. Nothing, no light at all. I say to my wife did you know they headlights were both out? She goes, Did you pull the switch out to turn them on? :banghead: Those are the fog lights honey. Had to drive 2 hours in the dark to the next place to buy bulbs. The fogs are useless alone but at least I still had hi beams to use.

 

[Steve in Chicago]

I say to my wife did you know they headlights were both out? She goes, Did you pull the switch out to turn them on? :banghead:

That is priceless!

 

[neonhomer]

Well, I swapped the other harness, and then changed the blown fuse. Everything seems to be working like it is supposed to. When I turn the key on, the DRL's come on. When I turn the switch to 12 o'clock, the low beams come on, and when I pull the switch out, the fogs come on.

One of the H7's is blown. I will replace both at the same time. Normally, I use the Silverstar Ultra's in my work car (Nissan Versa hatchback), but I go through them about every six months (especially when I drive four hours a day, and two of them are in the dark!) I was thinking about using them in the Passat, but I am concerned with the wiring harnesses. The one I rebuilt, I used 16ga wire. The other harness is one out of a junkyard, that was in like new shape. If I could buy the pins to go in the factory plugs for the back of the headlight housing, I would just build my own out of 16ga high temp wire.

Now my next feat is to get the Euroswitch. I already have the rear fog kit that I bought from a guy here a while back. Just got to find where I stashed it.

I have to say that I was clueless on how this worked. I thought the headlights were working, just not aimed right. Wow was I wrong...

 

[Steve in Chicago]

How's your night lighting now? I bet it's a whole new world better.

How are your headlight lenses? At the age of your car, they'd typically be fogged over pretty well. If they are fogged over, do the wet sanding and plastic polishing treatment to them and your night lighting will improve yet another world better.

The ultimate is euro style projector headlights with HID bulbs.

 

[neonhomer]

I'd love to do the Euro style with HIDs, but that's $$$...

Once I get the bulbs replaced, I will go from there.. I usually use the 3M headlight restoration kits. They work pretty good. Used them on my van and on my Jeep...

 

[hu vw]

One of the H7's is blown. I will replace both at the same time. Normally, I use the Silverstar Ultra's in my work car (Nissan Versa hatchback), but I go through them about every six months (especially when I drive four hours a day, and two of them are in the dark!) I was thinking about using them in the Passat, but I am concerned with the wiring harnesses.

I'm glad you were able to fix your problems. Try installing these. I've used them for years with no problems with the wiring harness and their longevity if excellent. The current pair I have installed is pushing 4 years.

 

[scotts13]

Or, Sylvania XtraVision - a step down from SilverStars. Not quite as bright, but still noticeably brighter than standard bulbs. They're reasonably priced, and last me 2-3 years.

 

[neonhomer]

Hmmmmm.. Those are a thought... For both the Passat and my work car... I was told by Slyvania that the Silverstar Ultra's burn out quicker because of the hotter light.

I still have to pull the passenger's side headlight out and back apart. The metal ring that goes around the bulb fell off inside the housing.