[N8N]

Hi all,

Am on my second set of Euro mirror glass for my E92... 1st set looked great and I didn't anticipate any problem but neither one dimmed and one didn't heat (as determined by inspection one cool dewy morning.)

Got my hands on a second set today, they both dim, but I suspect that cool dewy mornings may be a thing of the past soon if they aren't already. I don't want to get complacent with these and then find out this winter that they won't burn off the ice. How do you go about testing these? I understand that BMW does not tie these to the rear defogger like everyone else (on my Jeep when I retro'd heated mirrors I could test simply by turning the defogger on, waiting a few minutes, and then touching my fingers to the glass) but uses a complex control system etc.

The two solder spots that are visible on the back of the assemblies, are those for the heat or the electrochromic function?

As an aside, I discovered something today... apparently my Fenix pocket flashlight will not trip the sensor to dim the mirrors, but my LED Mag-Lite will, even though it's not appreciably brighter. Must be a light frequency thing?

[Deep_Blue]

Put them in the freezer overnight then hook them up?

[N8N]

ah, here, I found the info I was looking for

http://www.e90post.com/forums/showth...rs+temperature

I like the way you think, but that would only put frozen condensation off the mirrors not activate the heaters. I guess if I knew where the outside temp sensor was I could hit it with some dust-off to fake it out and make the car think it was cold outside, then mist some water on the mirrors to see if it burns off in the pattern of the heating elements or just evenly?

So... where *does* the outside temp sensor live?

[galahad05]

I thought it was one of the two sensors mounted on top of the hood tray in the engine bay, on the left side or right side? Can't remember which one.

[galahad05]

Um...just re-read what I posted. Not clear.
Very near the cabin microfilter housing.

Let me see if I can find a picture.

[galahad05]

Eh, close enough for this purpose. Found the pic via a google image search of "bmw n54 engine bay". This is a 1 series photo, but it's close enough.





See the tray at the top of the picture? I think the one on the passenger side, near (in front of) the DME cover. It's a little round sensor that's plugged into a little housing on the front/top of the tray.

[N8N]

you mean the thing that's pretty much opposite the pin switch for the alarm? cool, I'll give that a try soon as I find a can of dust-off... I know I've got some around here.

[John 070]

Are our systems that sophisticated? Most cars simply activate when the rear defrost is on...???

[N8N]

Yup, newer Bimmers are complicated beasties.

Sometimes all that extravagant technology blows you away and meaningfully makes your life better (e.g. adaptive xenons.)

Sometimes it just makes you want to pop over to Bavaria and grab a few engineers and yell "KEEP IT SIMPLE STUPID! I MEAN DUMMKOPF!"

In other news I swear I had at least three cans of dust-off but I'll be damned if I can find one now.

[Efthreeoh]

Originally Posted by galahad05

Um...just re-read what I posted. Not clear.
Very near the cabin microfilter housing.

Let me see if I can find a picture.

That sensor is the air quality sensor to close the recirculation door if you have the climate system set to auto recirculate.

The outside air temp probe is in the front bumper on the left side near the radiator inside the lower cooling intake.

The heating element in the mirrors work only up to an air temperature of 52 degrees F and only when the wipers are set to the auto-on function.

[Efthreeoh]

Originally Posted by N8N

Hi all,

Am on my second set of Euro mirror glass for my E92... 1st set looked great and I didn't anticipate any problem but neither one dimmed and one didn't heat (as determined by inspection one cool dewy morning.)

Got my hands on a second set today, they both dim, but I suspect that cool dewy mornings may be a thing of the past soon if they aren't already. I don't want to get complacent with these and then find out this winter that they won't burn off the ice. How do you go about testing these? I understand that BMW does not tie these to the rear defogger like everyone else (on my Jeep when I retro'd heated mirrors I could test simply by turning the defogger on, waiting a few minutes, and then touching my fingers to the glass) but uses a complex control system etc.

The two solder spots that are visible on the back of the assemblies, are those for the heat or the electrochromic function?

As an aside, I discovered something today... apparently my Fenix pocket flashlight will not trip the sensor to dim the mirrors, but my LED Mag-Lite will, even though it's not appreciably brighter. Must be a light frequency thing?

Get a Surefire P2X flashlight... Just don't look at the mirror when you use it...

[N8N]

Originally Posted by Efthreeoh

Get a Surefire P2X flashlight... Just don't look at the mirror when you use it...

Hah, I have a Fenix TK-41 on order, just don't have it yet.

I wouldn't consider either the P2X or TK-41 to be a "pocket flashlight" though. Awesome, yes, but not pocket.

I'm a little nervous about a flashlight using multiple CR123s, I've heard enough bad stories about 'splosions and stuff. I realize that they're rare, but still.

But anyway, the flashlight that I do carry in my pocket is a Fenix E-11 which is rated at 117 lumens - the LED maglite is rated at 131 lumens... but the Fenix doesn't do squat to dim the mirror while the Maglite does it right away. It's kind of odd; I guess the photocell in the mirror must be only sensitive to certain frequencies which the Maglite puts out but the Cree LED in the Fenix doesn't? Getting off topic but I find weird stuff like this interesting. It was just through coincidence that I had the Fenix on me today but the last time I was messing with the dimming mirrors I had the Maglite handy so it wasn't until today that I noticed any issue.

Also, the mirrors do not dim when reverse is engaged - but I kind of expected that as that is a standard Gentex mirror function option.

Back to the topic at hand - I still can't find any dust-off but I put a baggie full of ice on the sensor up near the cowl, did nothing. After more searching both online and on the car I think I found it in front of the intercooler, so I need to actually get some dust-off (or a can of Freon, shh, don't tell the EPA) to test.

[vapore0n]

Originally Posted by Efthreeoh

Get a Surefire P2X flashlight... Just don't look at the mirror when you use it...

I believe all he needs to do is point a flashlight at the light sensor on the rear view mirror (that little circle that is very noticeable)
You should see the rearview and side mirrors change.

[N8N]

Originally Posted by vapore0n

I believe all he needs to do is point a flashlight at the light sensor on the rear view mirror (that little circle that is very noticeable)
You should see the rearview and side mirrors change.

Yup, that's it. While holding your finger over the corresponding sensor on the front of the mirror.

The funny thing is, that that doesn't work with one particular flashlight, despite the fact that it appears stupid bright when you watch yourself do this process.

It works perfectly with an LED Maglite and I'm pretty sure an old Lowe's flashlight as well (which like the Fenix also uses a Cree LED, but an older one.)

*shrug* I dunno, I just find stuff like this interesting.

What I don't find interesting is that BMW apparently thought that it was smarter to introduce some complicated logic for switching on the heated mirrors and didn't bother to include "or, if the rear defrost is selected by the driver, go ahead and turn the mirrors on as well" into the programming. I find that kind of frustrating, since a simple switch and relay works perfectly well in plenty of other cars on the road and I'm not really sure what is accomplished by this logic other than introducing the possibility that a driver could be in a situation where he wants to have the mirrors heated, the logic doesn't automatically engage the heaters, and the driver has no way to manually override.

[gewse2k]

Hmm.. my mirrors are always heated. I don't have to put on the wipers, defrost, etc.
They are not even close to the e46 mirror heat... but they are always warm to the touch.. just not so scorching hot as the e46 mirrors were :-)

[galahad05]

Originally Posted by Efthreeoh

That sensor is the air quality sensor to close the recirculation door if you have the climate system set to auto recirculate.

The outside air temp probe is in the front bumper on the left side near the radiator inside the lower cooling intake.

The heating element in the mirrors work only up to an air temperature of 52 degrees F and only when the wipers are set to the auto-on function.

Oh my bad. You're right--I remember now.

[Clammy]

Originally Posted by Efthreeoh

That sensor is the air quality sensor to close the recirculation door if you have the climate system set to auto recirculate.

The outside air temp probe is in the front bumper on the left side near the radiator inside the lower cooling intake.

The heating element in the mirrors work only up to an air temperature of 52 degrees F and only when the wipers are set to the auto-on function.

Mine heat up in the winter (as evidenced by the melting snow/ice), when my wipers are off.

Cheers!

[N8N]

Well this is now irrelevant because before I could trick the mirrors into working, it actually got cool. I'm happy to report that they are working perfectly

Listening to my car idle in the driveway is depressing though, I need to tack weld the exhaust flap open or something, it sounds like garbage all rattling around... don't see an easy way to fix it other than just fixing it open...