Auto dash light problem
Thread Starter
Racer
Joined: Nov 2012
Posts: 332
Likes: 7
From: scottsdale az
Auto dash light problem
we are on a round trip from PHOENIX TO Denver currently in Raton,New Mexico. By the way, getting 29mpg on my 2012 coupe.
problem - While driving through a hard rain storm around twilight, the dash lights that had come on automatically suddenly turned off. Light switch was on auto and outside lights were on. After sometime they suddenly came back on and this happened several more times. it also happened when I used the manual light switch for the headlights.
Anyone ever have this issue? Could it have anything to do with the hard rain?
Another thing - when I rotated the dial on the stalk that is spring loaded, the dash lights came on but the headlights went off!!!
help please with comments or opinions or maybe a question.
problem - While driving through a hard rain storm around twilight, the dash lights that had come on automatically suddenly turned off. Light switch was on auto and outside lights were on. After sometime they suddenly came back on and this happened several more times. it also happened when I used the manual light switch for the headlights.
Anyone ever have this issue? Could it have anything to do with the hard rain?
Another thing - when I rotated the dial on the stalk that is spring loaded, the dash lights came on but the headlights went off!!!
help please with comments or opinions or maybe a question.
Team Owner
Joined: Sep 2000
Posts: 25,004
Likes: 2,706
From: Far NW 'burbs of Chicago
St. Jude Donor '13
we are on a round trip from PHOENIX TO Denver currently in Raton,New Mexico. By the way, getting 29mpg on my 2012 coupe.
problem - While driving through a hard rain storm around twilight, the dash lights that had come on automatically suddenly turned off. Light switch was on auto and outside lights were on. After sometime they suddenly came back on and this happened several more times. it also happened when I used the manual light switch for the headlights.
Anyone ever have this issue? Could it have anything to do with the hard rain?
Another thing - when I rotated the dial on the stalk that is spring loaded, the dash lights came on but the headlights went off!!!
help please with comments or opinions or maybe a question.
problem - While driving through a hard rain storm around twilight, the dash lights that had come on automatically suddenly turned off. Light switch was on auto and outside lights were on. After sometime they suddenly came back on and this happened several more times. it also happened when I used the manual light switch for the headlights.
Anyone ever have this issue? Could it have anything to do with the hard rain?
Another thing - when I rotated the dial on the stalk that is spring loaded, the dash lights came on but the headlights went off!!!
help please with comments or opinions or maybe a question.
My experience:
1. The sensor that tells the headlights to automatically turn on, also controls the day/night function of the dash light.
2. The headlights come on automatically, 15 seconds after you turn on the wipers. But that does not dim the dash lights.
3. If you are in rain with the wipers on, your headlights will automatically be on because of the wipers. If the rain/sky gets heavy/dark enough that the headlights would have come on for darkness, then the dash lights will go to the night setting. If the rain eases up, the dash lights may go back to the day setting.
There are some differences between the automatic tranny and stick shift, but basically:
Rotating the headlight switch toward yourself and releasing, will turn off the headlights/running lights, rotating it a second time will put the system back in Auto. There may be a relationship to the dash lights but I don't remember how it works.
Last edited by Gearhead Jim; Jul 1, 2013 at 02:47 PM.
Drifting
Joined: Jul 2011
Posts: 1,258
Likes: 99
From: O'Fallon Illinois - Currently own a 2016 Z06 1LZ A8 Coupe
The C6 lighting system is more complicated than you might expect.
My experience:
1. The sensor that tells the headlights to automatically turn on, also controls the day/night function of the dash light.
2. The headlights come on automatically, 15 seconds after you turn on the wipers. But that does not dim the dash lights.
3. If you are in rain with the wipers on, your headlights will automatically be on because of the wipers. If the rain/sky gets heavy/dark enough that the headlights would have come on for darkness, then the dash lights will go to the night setting. If the rain eases up, the dash lights may go back to the day setting.
There are some differences between the automatic tranny and stick shift, but basically:
Rotating the headlight switch toward yourself and releasing, will turn off the headlights/running lights, rotating it a second time will put the system back in Auto. There may be a relationship to the dash lights but I don't remember how it works.
My experience:
1. The sensor that tells the headlights to automatically turn on, also controls the day/night function of the dash light.
2. The headlights come on automatically, 15 seconds after you turn on the wipers. But that does not dim the dash lights.
3. If you are in rain with the wipers on, your headlights will automatically be on because of the wipers. If the rain/sky gets heavy/dark enough that the headlights would have come on for darkness, then the dash lights will go to the night setting. If the rain eases up, the dash lights may go back to the day setting.
There are some differences between the automatic tranny and stick shift, but basically:
Rotating the headlight switch toward yourself and releasing, will turn off the headlights/running lights, rotating it a second time will put the system back in Auto. There may be a relationship to the dash lights but I don't remember how it works.
I have an '06, A6. Can the sensor on the dash get fogged over time and start to mess with the Auto operation?
MT
Team Owner
Joined: Sep 2000
Posts: 25,004
Likes: 2,706
From: Far NW 'burbs of Chicago
St. Jude Donor '13
That's a good question. We had our 2006 for 3 yrs/44k miles, and our 2009 now for 4 yrs/60k miles. No indication of fogging or other troubles in the system.
But I have seen people suggest, when there is erratic operation of the lighting, to check the sensor for possible fogging or obstruction. I don't know if there have been actual problems, or it's just a logical thing to look for.
But I have seen people suggest, when there is erratic operation of the lighting, to check the sensor for possible fogging or obstruction. I don't know if there have been actual problems, or it's just a logical thing to look for.
Race Director
Joined: Mar 2005
Posts: 16,684
Likes: 1,193
From: La Center WA
When the headlight switch is in the "Auto" position, the headlights and dash lights are controlled by an ambient light sensor. Interestingly, the headlights will come on automatically if the wipers are on, even if the outside light level isn't dark enough to activate the headlights. In that case, it's entirely possible for the headlights to be on and for the dash lights to be at full brightness (as if the headlights were not on). Taking it a step further, the dash lights will dim once the ambient light level drops to a point where the light sensor calls for headlights on. Now if you were driving at twilight with occasional lightning flashes, the poor system wouldn't know what to do!
Anyway, I'm guessing that your headlights came on because your wipers were on (and not because it was sufficiently dark outside). I'm also guessing that your dash lights alternated between bright and dim (not off) because of changes in the ambient light levels brought about by the weather.
Anyway, I'm guessing that your headlights came on because your wipers were on (and not because it was sufficiently dark outside). I'm also guessing that your dash lights alternated between bright and dim (not off) because of changes in the ambient light levels brought about by the weather.
Thread Starter
Racer
Joined: Nov 2012
Posts: 332
Likes: 7
From: scottsdale az
Dash light question
Thx guys. I was actually gonna take the car in to a dealer until you gave such good explanations. it does seem like a complicated system and it was behaving as you described.
