lyleswk

Hey Bally family or anyone else.

My son's 03 has an issue with the running lights in the driver headlight. I looked for easy access to the back of the assemblies, but was met with no space, so thought I would research first.

What is going on is when he turns his headlights or running lights on, the driver's side running light does not come on. When he turns on the left turn indicator, it comes on. When I compare to the passenger side, it looks like separate bulbs, but it is hard to tell. And removing the headlights on this car is a total, well, you know.

Any thoughts?

Mister Bally

The turn signal and running light bulbs are separate. You need to either remove the battery & battery box to gain access to the bulbs. Photo shows the back of the headlight assembly (currently removed; long story, will post about it later).

2nd pic shows parking/running light bulb removed.

3rd pic shows turn signal bulb removed (connector with wire).

both bulbs are removed with a quarter turn ccw.
when checking the bulbs, check the bulbs using a volt meter in continuity mode to see if they are actually blown or not.

However, if a burned out bulb is your issue, the car should be beeping at you in the cabin and displaying a "Burned out bulb" error on the dashboard (assuming your lcd display is working, unlike mine). If this is not the case, best to check both bulbs (to be sure) and to removed the headlight switch in the cabin. It is possible that one of the copper contacts within the switch are either worn out or have carbon built up from the contacts moving and sparking (this is normal over time). Disassembling the headlight switch can be tricky, but with steady hands you will have no problem.

Hope that helps!

Mister Bally, Ballykid

lyleswk

That's perfect. Thanks. No, there is no light in the cabin. He also has an issue with one of his headlights coming on periodically. Wonder if it is the switch...

ballykid

I would guess that it is the switch if you aren't getting a light or beep in the cabin. But, it never hurts to check all of it especially because it's such a pain getting at the drivers side headlight.

Glad to help!

lyleswk

Well, finally had the car in town to look at this. Here is my confusion. The bulb you note in the second picture is not even connected to anything.. So don't know what that is.

Next, what is the multi pinned connector that is below the grey cap on the right in the 3rd picture? It looks like it may go to the running light, but is really hard to disconnect since the fiddly Audi connector release is on the bottom. And before I go to that effort, I wanted to check.

ballykid

The bulb in the second picture is the parking light bulb. If you notice in the second picture, the piece in my hand has 2 metal terminals on it. They make contact within the headlight assembly, so there is no wire connector going to the back of the bulb.

The open pin connector in the 3rd picture is for the main wiring harness to the headlight. They can sometimes be a pain to get off. I know my passanger side headlight is a pain.

lyleswk

Oh, didn't even think to look at that. Thanks.

Simon05

Just heard from the dealer and Audi Germany requested that the noise be documented and then they will give the fix to the dealer. Does this sound feasible? I have a feeling that this is going to take time to rectify. Maybe this gets done right the first time.

Skolacz1961

Though this is a very old thread, I’m resurrecting it to include additional information, as out of all the threads I’ve read regarding Running Lights, this has been the most helpful to my issue and I’m hoping the additional details are beneficial to someone.

I own an 02 TT Mk1 US model - being a US model is pertinent to what I’ve learned.

My particular issue was the front running lights did not illuminate when the headlight switch was set to the first position, however, the rear running lights did operate, fully engaging the switch to activate the headlights did not change the status of the front running lights.

Initially, I had the mistaken belief the front fender side marker lights were supposed to illuminate when the running lights were switched on (it’s one of those things I didn’t fully pay attention to when everything was operational), but have since determined that was inaccurate. Clouding my initial thinking, the front running light and side marker light would illuminate when the respective directional was commanded on, which falsely led me down the road of a faulty headlight switch; partly because the front running light position and directional appear to be the same light and my previously mentioned mistaken belief seeing the fender side marker light on as part of the running lights. Additionally, numerous threads that discuss various lighting issues, often indict the headlight switch as being the cause.

Replacing the headlight switch did not address the issue or change any symptoms.

Reviewing the Bentley manual closely, particularly the description of the Exterior bulb applications, page 94-3, it became apparent the Parking Light only consists of Front & Rear bulbs, and Turn Signal is listed as Front, Rear & Side, ultimately making two things clear: the Side marker is only associated with the Turn Signal, as well as, there are TWO bulbs in the headlight assembly that appear to illuminate the same location on the light.

As helpful as the Bentley manual was in this regard, other information it contains is misleading regarding US models, specifically, the image of the Headlight assembly on page 94-4 showing the parking/side bulb marker bulb plugs into the High beam and parking/side bulb holder - this is not accurate with US vehicles, at least my 02. Yes I have that holder, but there is not a bulb in the lower location. Worth mentioning, numerous YouTube videos, made from European sources, show that same bulb holder containing a bulb, so I can only speculate the Bentley is accurate for European models of the TT.

Which leads to the significance of this thread and the photos it contains; they are instrumental in pointing out the position of the two bulbs that share the same light position in the headlight assembly. Photo two specifies the location of the running light bulb. Worth noting, removal of each running light bulb assembly differs depending if it’s driver side or passenger side you’re trying to remove. The Passenger headlight assembly running light is removed by turning the bulb assembly clockwise, when viewed from the back of the headlight assembly. The Driver headlight assembly running light is removed by turning the bulb assembly counter-clockwise, when viewed from the back of the headlight assembly.

In my case, my issue was caused by the simplest of reasons - both bulbs had reached end-of-life around the same time. By the time I noticed, coupled with misremembering front side marker light operation, had me thinking multiple lights had failed simultaneously, driving me down a rabbit hole to nowhere - DOH!