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Old 27th July 2020, 07:31   #1
Odd Job
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Default Auto Dimming Rear View Mirror

Hi all,

I wonder if anyone has experienced this regarding the auto dimming rear view mirror.
This is the first car I've owned with one, and I'm not sure if I've got a problem, or if this is what they do!
I've not not driven it much at night, but on Friday I was.

Basically, does it work. YES. It works.
Does it work all the time, or rather when I need it to work. NO

I've noticed that a car with "standard" non dazzling headlights will cause it to darken.
But, I've noticed that if a vehicle has these more modern "turn the road into daylight" headlights, the damn thing wont operate!

I have a theory, I may be well off the mark, but it goes like this.
The mirror shouldn't darken in actual daylight.
So, if the car behind headlights have a beam which is in the daylight spectrum, it fools the sensor and so wont darken.
Does this sound possible?

Many thanks for any ideas and help!
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Old 27th July 2020, 08:18   #2
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Quote:
Originally Posted by Odd Job View Post
But, I've noticed that if a vehicle has these more modern "turn the road into daylight" headlights, the damn thing wont operate!

I have a theory, I may be well off the mark, but it goes like this.
The mirror shouldn't darken in actual daylight.
So, if the car behind headlights have a beam which is in the daylight spectrum, it fools the sensor and so wont darken.
Does this sound possible?

Many thanks for any ideas and help!
I haven't noticed, no, but....

Modern headlights have a much sharper cut off of the upper part of the beam, than older halogen designs and if they are dipped behind you, they probably would not appear bright enough to your mirror so as to cause it to dim.

A problem I do notice when reversing out of my dark garage, out into daylight, is that the mirror sees darkness ahead, bright behind and dims the mirror. A thumb over the sensor, bring it back to undimmed.
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Old 27th July 2020, 08:28   #3
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OK , many thanks.

I did notice it a few times, ( not dimming ) perhaps it's because I wear glasses that makes me more susceptible to being dazzled?

So, that leads me to ask another question.
Can I fit a non-auto dimming mirror without messing with the rain sensor?
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Old 27th July 2020, 08:53   #4
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OK , many thanks.

I did notice it a few times, ( not dimming ) perhaps it's because I wear glasses that makes me more susceptible to being dazzled?

So, that leads me to ask another question.
Can I fit a non-auto dimming mirror without messing with the rain sensor?

Instead of swapping the mirror to a non auto dip you could just unplug the current one to prevent it working that way it all looks the same and saves you buying a mirror.


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Old 27th July 2020, 08:57   #5
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Stupid question coming up, but I really dont know the answer!
So, when the unit is unplugged, it's dark all the time?
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Old 27th July 2020, 09:05   #6
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Stupid question coming up, but I really dont know the answer!
So, when the unit is unplugged, it's dark all the time?

I’m sure that it’s undimmed when unplugged so would just be a normal mirror.


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Old 27th July 2020, 09:11   #7
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Ah,
What I'm after is for it to dim more often, so unplugging it would't solve my issue.
I think it's probably down to me wearing specs, and I'm more susceptible to being dazzled.

I think the best thing I can do is see if I can convert it to a manual one, put the human back in charge of the machine!

If anyone know's if this is possible without messing with the wiper sensor, and know's what I'll need to do the job ( obviously a manual rear view mirror for a start, but if I need any different fixtures and fittings etc, ) please post and let me know.

Better still, if someone is breaking a 75 with a manual rear view mirror, please let me know!

Kind regards

Richard
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Old 27th July 2020, 09:13   #8
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Interesting thread, I’ve still to fit my dimming mirror but wondered if the fitting that’s bonded to the screen is the same for both mirror types?
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Old 27th July 2020, 09:19   #9
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I've had a quick look on fleabay, the non dimming mirror looks much smaller in both actual size and the part that goes to the screen.

I'm guessing that the way they fix is totally different.
It might not be a quick and easy swap over, it may be a bit more involved than I hoped.
I dont really want to destroy the self dim, as I want the option to change back if I have a change of heart, or when I sell my vehicle the new owner can put it back to how it was.
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Old 27th July 2020, 09:22   #10
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I see what you want to do now.
I wonder if the brighter lights are reflecting from the screen and confusing the sensor at the front of the mirror making it think it’s light and therefore not dimming the mirror.
I wonder if a filter over the front could help or maybe try tape so it’s dimmed all the time?
I believe they are the same fixing in the screen.


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