MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: acme on September 06, 2012, 05:30:33 pm

Title: Auto lights - very sensitive!
Post by: acme on September 06, 2012, 05:30:33 pm
Afternoon all,

First post and looking for some feedback/advice. Had mine for just over 4 years now and the auto lights have always been sensitive, I enquired when i first got the car and was told this is normal, however in the past few months I swear they've got a LOT more so, to the extent that yesterday sitting in the car in the shade of a building at 5pm the lights were on, which just can't be normal!?

So has anyone else experienced this and is there any known fix? Speaking to various people including VW they look at me dimly (get it! - sorry) and say just use the lights manually, thing is being a petrolhead I like my cars to work as intended, it's also a very useful feature.

Many thanks in advance, cheers.

PS Sorry if this is posted in the wrong section etc
Title: Re: Auto lights - very sensitive!
Post by: jedi-knight83 on September 06, 2012, 06:19:47 pm
have you had the front screen replaced and if so does it have a top tint?

If you still have an OEM screen then not sure what to suggest.

There is a bit in vagcom where you can adjust the sensor for different glass tints so might be worth checking that. Otherwise replace the sensor?

Title: Re: Auto lights - very sensitive!
Post by: acme on September 06, 2012, 10:11:15 pm
Thanks for the reply jedi knight.

Yes, I had a new screen in September of last year, they said it was the correct one and it has a cut out for the light sensor, but there's no doubt it started roughly then, could that be it?!

Someone on PH mentioned vagcom, is that on here, I think that's what needs doing, when I mentioned it to the VW dealer they didn't have a clue and had never done it!

This could take time I suspect!
Title: Re: Auto lights - very sensitive!
Post by: Eddie-NL on September 06, 2012, 10:19:12 pm
If it is coded for the wrong colour then it can cause the problem you are having
Title: Re: Auto lights - very sensitive!
Post by: rdfcpete on September 06, 2012, 10:27:38 pm
I had this minor issue with my GTI but was never really too fussed about it ultimately. There are about 4 months of the year solid where I would drive in only light that the auto switch used Xenons for because it was a little over sensitive  :grin: (These obviously being the winter months).

I see a lot of other cars doing the same thing, I don't think this is isolated to MK5's or VAG stuff. Quite often of a morning, facelift X5's, 7 series, Lexai' (several Lexus cars) and various Audi's will have their Xenons on when it's probably not even quite 'driving on side light' territory i.e. visibility is very good, if not maximised. I don't believe for a minute every one of these drivers has manually switched to headlights. Usually, it's the other way around - people driving beyond dusk on sidelights, sidelights & fogs or even DRL's still  :driver:

Maybe as a safety thing out the factory, they're aclimatised to be on rather than off if there's any doubt? I'm guessing here though  :chicken:
Title: Re: Auto lights - very sensitive!
Post by: jedi-knight83 on September 07, 2012, 08:16:51 pm
Thanks for the reply jedi knight.

Yes, I had a new screen in September of last year, they said it was the correct one and it has a cut out for the light sensor, but there's no doubt it started roughly then, could that be it?!

Someone on PH mentioned vagcom, is that on here, I think that's what needs doing, when I mentioned it to the VW dealer they didn't have a clue and had never done it!

This could take time I suspect!


get a sheet of white paper and hold it inside yout new front screen and then look at the paper from outside the car so your looking through the glass.

If it has a blue tint then its the correct colour (although if its not a VW screen it MAY still cause issues?)
If it has a green tint then its not the correct screen for the GTi.

I cant remember where it is on vagcom but in one of the convenience menus there is a bit where you can choose what screen tint you have for the sensor as different tint colours will allow different amounts of light through.

Either that or they somehow damaged the sensor while fitting the screen.
Title: Re: Auto lights - very sensitive!
Post by: Phil Miller on September 07, 2012, 08:55:08 pm
do your wipers wipe when you start up? if they do then its prob the sensor has a fault, my lights come on all the time (althou they did i havent driven it in ages :sad1: not long now  :jumpmove:)
Title: Re: Auto lights - very sensitive!
Post by: acme on September 13, 2012, 04:36:37 pm
Nope, as odd as it sounds it's neither blue or green, but just darker when you put the piece of paper inside the screen - thanks for suggestion.

Nope, the wipers don't come on either when starting up.

The more I look at it the more I'm convinced it's the sensor itself, being an early MK5 it has 6 or so visible cells in the sensor, two at 11 o'clock and 5 o'clock are twice the size of the rest, and they all more or less look squashed/like they have water on them. I think the gel pad/gasket that's designed to seperate screen from  sensor hasn't been put in, the question is has it damaged the sensor, if so it'll be bloody expensive to replace.

If anyone else has an early MK5 (latter ones have 4 cells in two distinct rows) please could you let me know if they're clear (as in clearly defined when you peer through the scree)? - Cheers
Title: Re: Auto lights - very sensitive!
Post by: trs888 on September 16, 2012, 04:20:24 pm
Nope, as odd as it sounds it's neither blue or green, but just darker when you put the piece of paper inside the screen - thanks for suggestion.

Nope, the wipers don't come on either when starting up.

The more I look at it the more I'm convinced it's the sensor itself, being an early MK5 it has 6 or so visible cells in the sensor, two at 11 o'clock and 5 o'clock are twice the size of the rest, and they all more or less look squashed/like they have water on them. I think the gel pad/gasket that's designed to seperate screen from  sensor hasn't been put in, the question is has it damaged the sensor, if so it'll be bloody expensive to replace.

If anyone else has an early MK5 (latter ones have 4 cells in two distinct rows) please could you let me know if they're clear (as in clearly defined when you peer through the scree)? - Cheers

hey, do these pics help?   2005 MK5 GTI

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi872.photobucket.com%2Falbums%2Fab286%2Ftrs888%2FSAM_1498.jpg&hash=577ef499e6217639d0a43ae9094b37f1f5e754b7)

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi872.photobucket.com%2Falbums%2Fab286%2Ftrs888%2FSAM_1498a.jpg&hash=d08168a8b220407e0f4d9991fda1c7485f8effbc)
Title: Re: Auto lights - very sensitive!
Post by: acme on September 17, 2012, 11:46:19 am
Nope, as odd as it sounds it's neither blue or green, but just darker when you put the piece of paper inside the screen - thanks for suggestion.

Nope, the wipers don't come on either when starting up.

The more I look at it the more I'm convinced it's the sensor itself, being an early MK5 it has 6 or so visible cells in the sensor, two at 11 o'clock and 5 o'clock are twice the size of the rest, and they all more or less look squashed/like they have water on them. I think the gel pad/gasket that's designed to seperate screen from  sensor hasn't been put in, the question is has it damaged the sensor, if so it'll be bloody expensive to replace.

If anyone else has an early MK5 (latter ones have 4 cells in two distinct rows) please could you let me know if they're clear (as in clearly defined when you peer through the scree)? - Cheers

hey, do these pics help?   2005 MK5 GTI

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi872.photobucket.com%2Falbums%2Fab286%2Ftrs888%2FSAM_1498.jpg&hash=577ef499e6217639d0a43ae9094b37f1f5e754b7)

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi872.photobucket.com%2Falbums%2Fab286%2Ftrs888%2FSAM_1498a.jpg&hash=d08168a8b220407e0f4d9991fda1c7485f8effbc)

You Sir are a gentleman and a scholar! Many thanks.

Yep, this is exactly the sensor I have (and appears to only be on early cars, the latter ones having two rows of diamond shape ones) and yours is much clearer and clearly defined. If I understand correctly the white looking sensor in the middle is the light one, the ones around the outside, including the two at 5 o'clock & 11 o'clock which are twice the size, are the wiper ones.

Can I ask have you had a new windscreen at any time?

And how sensitive are your lights, for example in shade during the middle of the day at this time of year would they come on?

I also noticed if I sprayed water on the sensor the lights would come on? Same with yours?
Title: Re: Auto lights - very sensitive!
Post by: john87 on September 17, 2012, 12:15:06 pm
Just to interject regarding your comment about the lights coming on when there's water on the sensor... I have noticed with my 2008 model that when heavy rain starts, after 3 or 4 constant sweeps of the wipers the lights are also activated, presumably due to the expected decrease in visibility caused by the rain - quite a handy feature which previous cars with 'Auto lights' did not have  :happy2:
Title: Re: Auto lights - very sensitive!
Post by: acme on September 17, 2012, 02:40:47 pm
Just to interject regarding your comment about the lights coming on when there's water on the sensor... I have noticed with my 2008 model that when heavy rain starts, after 3 or 4 constant sweeps of the wipers the lights are also activated, presumably due to the expected decrease in visibility caused by the rain - quite a handy feature which previous cars with 'Auto lights' did not have  :happy2:

Yep, that's what I figured too, seems like a 'sensible' feature, though I have to say that was only whilst spraying the screen/sensor manually with the car at a rest and no actual rain. I've never noticed this in the 4+ years of owning the car, but then if the lights come on whilst it's raining/probably darker I don't mind.
Title: Re: Auto lights - very sensitive!
Post by: acme on September 24, 2012, 04:00:06 pm
have you had the front screen replaced and if so does it have a top tint?


Hi jedi-knight,

Why the question re the top tint, are you thinking it will affect it?

Speaking to the windscreen company they've put one with a top tint in, they're coming back to put another clear one on to see if this fixes the problem. Speaking with VW HQ they quite logically stated that the tint will make it appear darker than it really is and so in anything other than bright sunlight the lights will come on!

Let's see what happens.....
Title: Re: Auto lights - very sensitive!
Post by: DSG-GTI on September 24, 2012, 09:10:28 pm
Anybody else notice that the lights come when a certain Motorway speed is achieved  :wink:
Title: Re: Auto lights - very sensitive!
Post by: acme on September 25, 2012, 05:29:02 pm
Anybody else notice that the lights come when a certain Motorway speed is achieved  :wink:

Fairly certain I've seen this in writing somewhere, the manual possibly, after a certain amount of time above a specific speed they'll turn on, safety feature presumably.
Title: Re: Auto lights - very sensitive!
Post by: trs888 on February 11, 2013, 10:50:32 pm
Nope, as odd as it sounds it's neither blue or green, but just darker when you put the piece of paper inside the screen - thanks for suggestion.

Nope, the wipers don't come on either when starting up.

The more I look at it the more I'm convinced it's the sensor itself, being an early MK5 it has 6 or so visible cells in the sensor, two at 11 o'clock and 5 o'clock are twice the size of the rest, and they all more or less look squashed/like they have water on them. I think the gel pad/gasket that's designed to seperate screen from  sensor hasn't been put in, the question is has it damaged the sensor, if so it'll be bloody expensive to replace.

If anyone else has an early MK5 (latter ones have 4 cells in two distinct rows) please could you let me know if they're clear (as in clearly defined when you peer through the scree)? - Cheers

hey, do these pics help?   2005 MK5 GTI

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi872.photobucket.com%2Falbums%2Fab286%2Ftrs888%2FSAM_1498.jpg&hash=577ef499e6217639d0a43ae9094b37f1f5e754b7)

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi872.photobucket.com%2Falbums%2Fab286%2Ftrs888%2FSAM_1498a.jpg&hash=d08168a8b220407e0f4d9991fda1c7485f8effbc)

You Sir are a gentleman and a scholar! Many thanks.

Yep, this is exactly the sensor I have (and appears to only be on early cars, the latter ones having two rows of diamond shape ones) and yours is much clearer and clearly defined. If I understand correctly the white looking sensor in the middle is the light one, the ones around the outside, including the two at 5 o'clock & 11 o'clock which are twice the size, are the wiper ones.

Can I ask have you had a new windscreen at any time?

And how sensitive are your lights, for example in shade during the middle of the day at this time of year would they come on?

I also noticed if I sprayed water on the sensor the lights would come on? Same with yours?

Not sure about the lights coming on under heavy rain. i will have to try it. but dont think they come on just spraying the sensor.
my lights are sensitive to the extent that it can be a sunny day and theyre on. do come on in shade tho. not sure what the parameters are .
Title: Re: Re: Auto lights - very sensitive!
Post by: SI-R32 on February 12, 2013, 08:50:37 am
The function of the auto lights is all covered in the manual guys, as soon as you pop over approx 100mph on motorway they will come on and not go off till you have done about 5 mins of driving below 60 kmph.

The lights will also come on as stated after the 4th constant wipe of the windscreen wipers either in there auto mode or constant mode.

Other than that they can be a bit annoying at times when its a dark day or your going through a tunnel etc