BimmerFest BMW Forum banner

Dimming Side Mirrors?

84K views 54 replies 18 participants last post by  mrpingu 
#1 ·
Let's talk real fast about the auto-dimming side mirrors. I swore I read that my truck is supposed to have them (M-Sport, Tech, Prem, etc so I think it should) but I've never seen them actually dim. How do they work? Do I need to turn them on? My center rearview mirror does dim like it should, but I'm still getting blinded by lifted trucks with aftermarket HIDs stuffed in every orifice and it makes me nuts.

Do they work on any of your trucks? How?
 
#3 ·
[...] read that my truck [...]
X3 is definitely NOT a truck.

A truck according to Merriam-Webster:
[...]
3: a wheeled vehicle for moving heavy articles: as
a : a strong horse-drawn or automotive vehicle (as a pickup) for hauling
b : a small barrow consisting of a rectangular frame having at one end a pair of handles and at the other end a pair of small heavy wheels and a projecting edge to slide under a load -called also hand truck
c : a small heavy rectangular frame supported on four wheels for moving heavy objects
d : a small flat-topped car pushed or pulled by hand
e : a shelved stand mounted on casters
f : an automotive vehicle with a short chassis equipped with a swivel for attaching a trailer and used especially for the highway hauling of freight; also : a truck with attached trailer
[...]
Please teach yourself not to use this word as a such an incorrect description.
 
#12 ·
I have the same problem on my 2013. My vehicle has been in service two times for this issue. First they replaced the rearview mirror because the side mirrors weren't dimming at all. When I still complained, the dealer brought in an engineer who said BMW changed the programming for 2013 since people were complaining that the mirrors got too dark. It is really annoying but they said not enough people were complaining to warrant a fix. My 2012 X3 loaner worked a lot better. From experience, the mirrors will only darken when you have a motorcycle or a vehicle with high beams directly behind you. Glad I came across this thread.
 
#15 ·
I need this. Per my prior posts, I have confirmed my rear view side mirrors do not dim as they should. I will ask my SA if coding can fix it.
 
#16 ·
I don't think a 2012 mirror will fit our 2013. The brackets and stem are different if you look closely. Even the mirror itself is different (the flashing red light is larger on the 2013). If it is a coding thing, that would be awesome.

As for testing your 2013 mirrors- put your hand behind the sensor of the rear view until it darkens. Then while holding your hand there, shine a flashlight into the front sensor. Your sides should darken. In any other vehicle with this feature, the sides will darken while only blocking the sensor (how my x3 loaner worked). For those experiencing this issue, take your cars to the dealer and have them file a report. The engineer said the more people bothered, the more likely a fix is released. I could take a short video showing you what I am talking about if you want.
 
#17 ·
I have found the following factor...

JBBE
3080 InteriorMirror
CODDT_01_SCAL_DIM_ECR_LIN

by the german description this sets dimming of the door mirrors to be set by the inside mirror by the following formula

Door Mirror =(Interior mirror/32)*Factor

my factor is werte = 20 which would be 32 in hex, so the outside would be set to the same as the inside. Since we are talking about dimming, I think if you want the outside to be darker you would increase the multiplier factor.

haven't tried it, but it could be a starting point.
 
#21 ·
Here are all of my relevant values, some are talking about ambient light sensors and some are talking about the blind sensors so I think we're on the right track. Seems to be separate values for normal dark and light.

Can someone with a 2011 or 2012 car post the same values for these keys and we can compare? Seems like all the "01" values are zero, not sure why.

 
#22 ·
it seems that most of these relate to the glare sensors. As the interior mirror reacts appropriately, I don't think we want to mess with these.
I didn't see before the CODDT_00_SCAL_DIM_ECR_LIN
which may be a factor we can manipulate.

I tried altering the CODDT_01_SCAL_DIM_ECR_LIN to no effect. I took it to Werte=30 and to Werte=00.
 
#23 ·
It seems like the 01 values don't do anything for us.

What is your 00 SCAL DIM ECR LIN set to by default? Any other clues as to what we can change? I'm hoping we can find a value that is different from 2012 to 2013 and that we can just plug in the 2012 value and have the correct behavior. Seems that dream is getting further away though...
 
#26 ·
The dazzle light settings you mentioned may be the key to this...

CODDT_00_SCAL_SEN_DAZZ_00_LIN "normal" setting for sensors
74
Werte = 4A
the hex equivalent of 74 is 4A
CODDT_00_SCAL_SEN_DAZZ_01_LIN "dark" setting for sensors
26
Werte = 1A
again hex equivalent.
same for
CODDT_00_SCAL_SEN_DAZZ_02_LIN "light" setting for sensors
100
Werte = 64

These may change the way the mirrors respond to light but wouldn't necessarily differentiate between inside and outside mirrors.
 
#29 ·
2013 X3 side mirrors NOT dimming

i too have the same problem - my wife's 2013 x3 (with premium package) side mirrors do not dim. I cannot accept "this is how it is" answer from the dealer/BMW. We should all complain to force BWM to correct the issue. Remember people, we paid for the dimming feature. The auto-dimming glass costs more than double the non-dimming one. I know, i just paid $350 to replace an auto-dimming side mirror glass on my 2008 335. By the way, the side mirrors on my 335 dim beautifully. I would not buy another car without this feature.
 
#30 ·
Brought the car to the dealer for checks. They found the rear mirror defected. Apparently, the (inside) mirror controls how the side mirrors dim with its front and back light sensors. Will have rear mirror replaced in two weeks and let you know if this fixes the problem.
 
#34 · (Edited)
Wouldn 't there be an analog voltage that we can measure at the side mirrors ? (the "control" voltage that must be sent to vary the dim level) I'm not quite sure how it works or which wire to check, but maybe we could compare 2012 to 2013 voltages ? Or we could manually vary the voltage and see if the mirror goes from bright to dim ? Just to see if it's a "hardware" or "coding" issue ?
 
#35 ·
I didn't see any mention of it in this thread, but according to page 54 in the pdf manual... turning the security light dome on the bottom of the rearview mirror should adjust the dimming level. I'm on vacation right now so I can't test in my vehicle, can anybody confirm?
 
#36 ·
Just to add my 2 cents on the original question.

I can visibly see my side mirrors dimming at night when a car with bright lights is behind. I can detect an edging effect where the edge of the mirror stays as normal, but the main body of the mirror dims a little. Then you can see the difference in shading.

Maybe try this at night. My stupid idea would be to park up at night and shine a torch on the rear view mirror sensor to make it dim. Check the rear view dims, then check on the sides?

J
 
#39 ·
update

got the rear mirror replaced. The rear mirror now dims well at night, but the side mirrors still do NOT dim very well. I did a test with the flashlight beaming on the side mirror while covering the light sensor on the rear mirror (no light) - the side mirror seem to work in this test i.e. the glass turn greenish. my conclusion would be the dimminsg function on the side mirros does not work properly. Maybe it has some ting to do with programing. Brought the car back to the dealer. They did a few tests and said it's just the way it is :mad: No sure what to do next, but won't ive up.
 
#40 ·
Well, I placed a piece of tape with a small hole cut in it across the sensor on the back of my mirror to see if it improves the dimming feature. My thought was that there must be comparison between the ambient light (rear of mirror) with the light from the front mirror side.

To be honest I can't tell very much difference. My next test is to completely cover the rear sensor to see if the mirrors dim more quickly.

I can't believe I have to use duct tape on a (near) $70,000 car. :(
 
Top