headlights comming on when light out??
Thread Starter
Senior Member
Joined: Jan 2010
Posts: 456
Likes: 4
From: Canada
2003 c240 4matic wagon
headlights comming on when light out??
Ok im in Canada and have DRL cannot turn them off by cluster! im talking all my lights not DRL
my switch is set to auto
anways i noticed last night about 6pm est when i started the car the lights all came on. the dash lit up and such it was still very light out I turned the switch to off but everything stayed on was in park e brake was on.
turned engine off set switch to off turned power on via key (engine off) switch worked i could turn lights on and off. started car same as 1st time lights on cant turn them off (dash lights)
put flashlight on light sensor they turned off so it works
this morning 9am started car lights came on right away it was sunny out about 5c after about 2 mins driving lights turned themselves off
NOW I dont recall the lights ever being on when it was light out so wtf???
windshield is clean NO work/changes done to cause this
any ideas??
my switch is set to auto
anways i noticed last night about 6pm est when i started the car the lights all came on. the dash lit up and such it was still very light out I turned the switch to off but everything stayed on was in park e brake was on.
turned engine off set switch to off turned power on via key (engine off) switch worked i could turn lights on and off. started car same as 1st time lights on cant turn them off (dash lights)
put flashlight on light sensor they turned off so it works
this morning 9am started car lights came on right away it was sunny out about 5c after about 2 mins driving lights turned themselves off
NOW I dont recall the lights ever being on when it was light out so wtf???
windshield is clean NO work/changes done to cause this
any ideas??
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From: VA
THE C350
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Light sensor getting a little cranky - Just leave it on Auto & forget about it. Make sure that there is no mineral or silicone deposit build up on your screen in the sensor area. It will usually screw with the rain sensor first if you have one.
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Joined: Dec 2006
Posts: 2,403
Likes: 64
From: Camas, WA
2007 C230SS; 2014 ML350 BT
There is an adjustment that can be made to the light sensor in STAR, but I have found it's range of adjustment seems very limited. Mine comes on when it is light out too. I have had 2 windshield replacements, and this last one the light sensor just doesn't work near as good as the last ones.
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
+1 - Does the damn thing make any difference at all? A very pernickety friend of mine used to check his with a Minolta light meter & drove MBSA mad trying to calibrate it to his satisfaction. As far as I'm concerned as long as lights are on well before dark it's OK.
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MBWorld Fanatic!
Joined: May 2009
Posts: 1,101
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From: Toronto, NYC
2002 Mercedes Benz C230 Coupe
Ok im in Canada and have DRL cannot turn them off by cluster! im talking all my lights not DRL
my switch is set to auto
anways i noticed last night about 6pm est when i started the car the lights all came on. the dash lit up and such it was still very light out I turned the switch to off but everything stayed on was in park e brake was on.
turned engine off set switch to off turned power on via key (engine off) switch worked i could turn lights on and off. started car same as 1st time lights on cant turn them off (dash lights)
put flashlight on light sensor they turned off so it works
this morning 9am started car lights came on right away it was sunny out about 5c after about 2 mins driving lights turned themselves off
NOW I dont recall the lights ever being on when it was light out so wtf???
windshield is clean NO work/changes done to cause this
any ideas??
my switch is set to auto
anways i noticed last night about 6pm est when i started the car the lights all came on. the dash lit up and such it was still very light out I turned the switch to off but everything stayed on was in park e brake was on.
turned engine off set switch to off turned power on via key (engine off) switch worked i could turn lights on and off. started car same as 1st time lights on cant turn them off (dash lights)
put flashlight on light sensor they turned off so it works
this morning 9am started car lights came on right away it was sunny out about 5c after about 2 mins driving lights turned themselves off
NOW I dont recall the lights ever being on when it was light out so wtf???
windshield is clean NO work/changes done to cause this
any ideas??
When your instrument cluster is not lit, but the low beam headlamps are, thats DRL mode (daytime). When the low beam headlights, city lights and instrument cluster are lit up, thats full headlight mode (night time).
When its gloomy (like at 9am est today in Canada
), the car cant decide if it should be in DRL mode or headlight mode, hence it switched on headlights, and then switched them off after it figured out that there was enough ambient lighting to not need headlights.
Senior Member
Joined: Oct 2009
Posts: 333
Likes: 2
From: NYC
2007 C280 4Matic
My lights turn on and off several times during a given drive to or from work. They turn on through tunnels, under cloud cover, and if the sun is at my back, I always thought it was a safety feature so I can be spotted out in a sea of glare.
I'm banking on the light sensor only being sensitive to a certain UV spectrum of light, as I have problems when the lights don't turn on in the rain. (I have to reach over and turn the switch whats up with that
)
I'm banking on the light sensor only being sensitive to a certain UV spectrum of light, as I have problems when the lights don't turn on in the rain. (I have to reach over and turn the switch whats up with that
)
