headlight sensor

1MOREMOD · 04-18-2010, 11:04 AM

anyone know where the sensor is that tells the headlights how dark it is and turns them on. is it in the windshield with the rain sensor? thanks

1MOREMOD · 04-18-2010, 12:29 PM

messed around with it backing out of the garage. can make them turn on as soon as the windshield is in the shade but thought i would be able to trick it to turn off with a flashlight on the same area and didnt work? is there a sensor in both the windshield and the headlights?

///M Rakete · 04-18-2010, 06:05 PM

My understanding is that the rain sensor serves both purposes. Darkness signals the headlights to turn on and frequent changes (but not darkness), as drops of water would cause, signals the wipers. It should be noted that the sensor stares upwards into the sky, not straight ahead. This is why on a winter's afternoon even in full sunlight the headlights might come on when in the summer or on a cloudy day they wouldn't. The sensor is actually sensitive to infrared, not visible light, portion of the spectrum and a clear, blue sky in the winter months is pretty "cold" just like a night one.

1MOREMOD · 04-18-2010, 11:05 PM

so thats why i couldnt trick it with the flashlight? i just dont want my headlights to be on all the time if i tint the lenses.

///M Rakete · 04-19-2010, 08:10 AM

Quote:

Originally Posted by chriszeh

so thats why i couldnt trick it with the flashlight? i just dont want my headlights to be on all the time if i tint the lenses.

Tint away.

ersin · 04-19-2010, 10:40 AM

Maybe you could use an infrared light in place of the flashlight?

04-18-2010, 11:04 AM	#1
1MOREMOD - 11817 Rep 23,187 Posts Drives: Race car-> Join Date: Mar 2009 Location: check your mirrors iTrader: (5)	headlight sensor anyone know where the sensor is that tells the headlights how dark it is and turns them on. is it in the windshield with the rain sensor? thanks __________________ 02 Tiag e46 M3\|6MT\|GC plates\|MCS c.o.\|GC bars\|GC race control arms\|GC bushings\|BW eng. & tran. mounts\|subframe kit\|BW race shifter\|BW Jaffster\|Euro header\|BW exhaust\|K&N c.a.i.\|Epic race tune\|Rouge pulleys\|Seibon CF hood\|CSL bumper\|apr gt 250 & splitter\|ST-40\|XR-2\|SS lines\|half cage\|Recaro profi\|Profi 2 harness\|BMWpedals\|BW studs\|
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04-18-2010, 12:29 PM	#2
1MOREMOD - 11817 Rep 23,187 Posts Drives: Race car-> Join Date: Mar 2009 Location: check your mirrors iTrader: (5)	messed around with it backing out of the garage. can make them turn on as soon as the windshield is in the shade but thought i would be able to trick it to turn off with a flashlight on the same area and didnt work? is there a sensor in both the windshield and the headlights? __________________ 02 Tiag e46 M3\|6MT\|GC plates\|MCS c.o.\|GC bars\|GC race control arms\|GC bushings\|BW eng. & tran. mounts\|subframe kit\|BW race shifter\|BW Jaffster\|Euro header\|BW exhaust\|K&N c.a.i.\|Epic race tune\|Rouge pulleys\|Seibon CF hood\|CSL bumper\|apr gt 250 & splitter\|ST-40\|XR-2\|SS lines\|half cage\|Recaro profi\|Profi 2 harness\|BMWpedals\|BW studs\|
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04-18-2010, 06:05 PM	#3
///M Rakete Rocket Scientist 33 Rep 948 Posts Drives: BMW 2018 X3 M40i Join Date: Aug 2009 Location: Utah iTrader: (4)	My understanding is that the rain sensor serves both purposes. Darkness signals the headlights to turn on and frequent changes (but not darkness), as drops of water would cause, signals the wipers. It should be noted that the sensor stares upwards into the sky, not straight ahead. This is why on a winter's afternoon even in full sunlight the headlights might come on when in the summer or on a cloudy day they wouldn't. The sensor is actually sensitive to infrared, not visible light, portion of the spectrum and a clear, blue sky in the winter months is pretty "cold" just like a night one. __________________ 2015 BMW M5 Sedan Returned to BMW at end of lease.
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04-18-2010, 11:05 PM	#4
1MOREMOD - 11817 Rep 23,187 Posts Drives: Race car-> Join Date: Mar 2009 Location: check your mirrors iTrader: (5)	so thats why i couldnt trick it with the flashlight? i just dont want my headlights to be on all the time if i tint the lenses. __________________ 02 Tiag e46 M3\|6MT\|GC plates\|MCS c.o.\|GC bars\|GC race control arms\|GC bushings\|BW eng. & tran. mounts\|subframe kit\|BW race shifter\|BW Jaffster\|Euro header\|BW exhaust\|K&N c.a.i.\|Epic race tune\|Rouge pulleys\|Seibon CF hood\|CSL bumper\|apr gt 250 & splitter\|ST-40\|XR-2\|SS lines\|half cage\|Recaro profi\|Profi 2 harness\|BMWpedals\|BW studs\|
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04-19-2010, 10:40 AM	#6
ersin Brigadier General 126 Rep 4,144 Posts Drives: 17 YMB F80 M3 Join Date: Mar 2008 Location: Maryland iTrader: (1)	Maybe you could use an infrared light in place of the flashlight? __________________ 2017 F80 YMB.
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