Self levelling headlights aren't

[rikrose]

The headlights aren't choosing their level on startup, and are currently stuck in the top high position, as far as I can tell. I've let it stand at the services, locked. Overnight to today, also locked, and this evening they still didn't align to a sane position.

So, what could be wrong, and where do I look to try to diagnose it? Tomorrow (Sunday) I'm going ot be in Wales poking at cars all day, so there shoul dbe a toolkit to hand - I just need to know what to look for.

I don't really want to blind other motorists all the way home

[shineydave]

there's two sensors to detect the attitude of the car, one on the nearside lower wishbone and another on the rear (can't remember what side though,) could be one of the straps that connect them to the body that has come adrift

[rikrose]

I've jsut had both rear wishbones replaced. What am I looking for on them?

[shineydave]

should be a "box" with a strap or arm that attaches to the body, sort of like a switch, they detect load in the car and adjust the headlamps accordingly

[lemond]

Ah so thats what those crappy little lever arms are on the suspension. They look like parts off remote controlled cars.. Or Subarus

[shineydave]

yup they're the ones, like a giant remote servo

[rikrose]

Found the rear one - it's also on the nearside on my 99.5 model. It looks connected, but damn hard to reach without jacking the car up. I'll get it up on a jack tomorrow to check the connections. While I'm rummaging, is there anything else anyone can suggest?

[Philws4]

Found the rear one - it's also on the nearside on my 99.5 model. It looks connected, but damn hard to reach without jacking the car up. I'll get it up on a jack tomorrow to check the connections. While I'm rummaging, is there anything else anyone can suggest?

Come home before the sun goes down!!

Once you have the car up in the air you should be able to spot any loose wires quite easily. So if nothing is loose then i guess a sensor could be shagged!

Can you do a VAGCOM test/scan?

[shineydave]

can't you manually wind the headlight down to a reasonable angle to get you home

[PetrolDave]

Yopu need to do a VAG-COM scan of the headlight levelling module (address 55) to see what fault codes it is reporting.

That should tell you which sensor it thinks is faulty, or if it's some other problem.

[rikrose]

Poked at it and couldn't find anything loose. Everything seemed fine by inspection, but I handn't got it up on axle stands or a ramp or anything. Booked in at the Main Stealers. Will see what they say.

[rikrose]

They rang me at 10:30, having had the car for 2 hours. They called me to say the manual adjustment was wrong, and that one bulb had blown. They'd fixed both, and that'll be 20 quid more than the labour rate for an hour's work.

Looks like I have something to drive to and from the club tonight...

[QuantumJohn]

How can the manual adjustment become wrong?

To adjust the headlight level on a car with Xenons you have to plug in Vag-com set the headlight level to 'adjust', manually adjust them and then take the headlights out of 'adjust' mode with vag-com. The senors then ensure the headlights are always at the level set.

So even if the manual adjustment was wrong the sensors should ensure the headlights aim is correct. Headlights don't just manually adjust themselves!

John

[ChipHazzard]

Just to follow on from John's comments above which is the correct way to adjust the headlight's,

If you don't use VAG-com to set the headlights to adjust, before manually adjusting them you get an error code back saying headlights not aligned, as I have this as I forgot when I tried setting my headlights

[MarkB]

I adjusted mine without putting them in set mode. The light has no knowledge of the fact it is being moved. The motors only move the light depending on the ride height front and rear.