Rear view mirror potentially faulty

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twist
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Joined: Sun Mar 17, 2019 7:38 pm

Rear view mirror potentially faulty

Post by twist » Sun Jul 07, 2019 12:23 pm

I noticed that my rear view mirror always seems the same shade of “medium dim”. I expected it to look normal in normal daylight and then dim at night.

Am I misunderstanding how it works? Mine always seems to be dim. Not totally dark but not particularly clear in the daytime.

Should it just look like standard rear view glass under normal (well lit) driving conditions or does it sound like mine isn’t working right?
UK 1.5 DSG R-line in Indium Grey
Keyless, park assist, rear view cam, driver assist pack plus, lumbar support
Ordered: 11/12/19 / Collected 20/03/20

Impala
Posts: 2077
Joined: Sat May 12, 2018 3:03 pm

Re: Rear view mirror potentially faulty

Post by Impala » Sun Jul 07, 2019 2:56 pm

It should be the same day and night and only dims at night when there is another vehicle (close) behind with headlights on.

The dimming operation is controlled by 2 sensors, one for the ambient light level (day or night) and one to detect the presence of headlights behind at night. These operate 'in series', ie both need to be triggered to dim the mirror.

On my previous Golf, there was also an On/Off button on the mirror which would completely deactivate the dimming when Off.

With it being summer, I haven't had a chance yet to confirm my mirror is working but I noticed that the On/Off button is not present on the T-Roc, which should mean the dimming is always active and controlled only by the sensors. Another cost reduction I suppose.
1.5 TSI DSG R-Line MY19 Indium Grey, rear view camera, park assist.
Ordered 22/06/18
Built w/c 25/03/19 :(
With dealer 13/05/19 :P
Collected 20/05/19 :D

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twist
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Re: Rear view mirror potentially faulty

Post by twist » Sun Jul 07, 2019 3:06 pm

Impala wrote:
Sun Jul 07, 2019 2:56 pm
It should be the same day and night and only dims at night when there is another vehicle (close) behind with headlights on.

The dimming operation is controlled by 2 sensors, one for the ambient light level (day or night) and one to detect the presence of headlights behind at night. These operate 'in series', ie both need to be triggered to dim the mirror.

On my previous Golf, there was also an On/Off button on the mirror which would completely deactivate the dimming when Off.

With it being summer, I haven't had a chance yet to confirm my mirror is working but I noticed that the On/Off button is not present on the T-Roc, which should mean the dimming is always active and controlled only by the sensors. Another cost reduction I suppose.
Cheers Impala.

Are you saying that there’s always a slight dimming in effect regardless of conditions? Like a greenish tint? That’s what I’m seeing and in all honesty it’s a little dark for my taste. Not dangerously so but still darker than I’d like.

Might get the garage to check it anyway when I’m in for the engine update.
UK 1.5 DSG R-line in Indium Grey
Keyless, park assist, rear view cam, driver assist pack plus, lumbar support
Ordered: 11/12/19 / Collected 20/03/20

Impala
Posts: 2077
Joined: Sat May 12, 2018 3:03 pm

Re: Rear view mirror potentially faulty

Post by Impala » Sun Jul 07, 2019 3:55 pm

The old dipping mirrors had a lever which changed the angle of an internal rear silvered surface so as to point to the dark roof lining, leaving only the reflection off the front glass to provide the view behind with a much reduced brightness.

The new automatically dimming mirrors use an electrochromic meterial which changes the colour of an internal layer between the front glass and rear silvered layers of the mirror when a variable voltage is applied. The sensors on the mirror increase the voltage as the intensity of the lights from behind increases, so gradually dimming the reflected image.

It's like those sunglasses which react to light, but they use a photochromic meterial that changes colour just with the intensity of the light rather than requiring a voltage to be applied. Who wants batteries in their sunglasses :lol:

Anyway, I haven't yet seen the T-Roc mirror in dimmed mode but from memory of my Golf, the lights of the car behind beacame a greenish colour as the dimming increased.

I had a look at my T-Roc just now, in daylight and holding a sheet of white paper under the internal LED roof lights, angled to see the illuminated spot. It had the normal bluish LED tint and no indication of any greenish tint either on the illuminated spot or the surrounding white paper with just ambient light. Much as I'd expect.

If you are seeing a distinct greenish tint in daylight then that would suggest something isn't right and a visit to the dealer is on the cards.
1.5 TSI DSG R-Line MY19 Indium Grey, rear view camera, park assist.
Ordered 22/06/18
Built w/c 25/03/19 :(
With dealer 13/05/19 :P
Collected 20/05/19 :D

Hawkeye
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Re: Rear view mirror potentially faulty

Post by Hawkeye » Mon Jul 08, 2019 10:32 pm

IMO with the blacked out rear windows there is little change on the rear view mirror. Same was true on my Audi’s as well. They do dim, but the noticeable effect is mi i al due to the rear blacked windows
R-Line 2.0TSi DSG 4MOTION
Silver White with Black Roof
Panoramic Sunroof
'Beats' Sound system
Electric Tailgate
Rear View Camera
Park Assist
Driver Assistance Pack Plus

Ordered 20-10-18
Collected 19-03-19

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twist
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Re: Rear view mirror potentially faulty

Post by twist » Mon Jul 08, 2019 10:55 pm

Hawkeye wrote:
Mon Jul 08, 2019 10:32 pm
IMO with the blacked out rear windows there is little change on the rear view mirror. Same was true on my Audi’s as well. They do dim, but the noticeable effect is mi i al due to the rear blacked windows
Yeah, like I say, I’ve never had an auto dimming one so maybe this is just how they are (and as you say, minimal change with tinted rear window).
UK 1.5 DSG R-line in Indium Grey
Keyless, park assist, rear view cam, driver assist pack plus, lumbar support
Ordered: 11/12/19 / Collected 20/03/20

Impala
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Joined: Sat May 12, 2018 3:03 pm

Re: Rear view mirror potentially faulty

Post by Impala » Tue Jul 09, 2019 3:30 pm

My Golf had similar darkened rear windows, and the dimming of the mirror with dazzling headlights was unmistakable. Admittedly, the rear side windows on the T-Roc look a bit darker than on the Golf, but I'm not sure if the rear screen is equally darkened.

The only way to know for sure is to test it in the dark. The Golf had the advantage of having a switch on the mirror, so you could turn the dipping off and on and actually watch the dimming take place. It usually took about 2-3 seconds to reach maximum dimming for a car close behind. I don't think it would be possible to test this sitting stationary in your car at night and shining a bright torch on the mirror, but it might be worth a try.

At night, the mirror isn't permanently dimmed, and as a car approaches from behind, the dimming should gradually increase.
1.5 TSI DSG R-Line MY19 Indium Grey, rear view camera, park assist.
Ordered 22/06/18
Built w/c 25/03/19 :(
With dealer 13/05/19 :P
Collected 20/05/19 :D

Impala
Posts: 2077
Joined: Sat May 12, 2018 3:03 pm

Re: Rear view mirror potentially faulty

Post by Impala » Fri Jul 12, 2019 7:07 pm

twist wrote:
Sun Jul 07, 2019 12:23 pm
I noticed that my rear view mirror always seems the same shade of “medium dim”. I expected it to look normal in normal daylight and then dim at night.

Am I misunderstanding how it works? Mine always seems to be dim. Not totally dark but not particularly clear in the daytime.

Should it just look like standard rear view glass under normal (well lit) driving conditions or does it sound like mine isn’t working right?
Hi Twist.

Just wondering if you have made any progress with this.

Also, I came across another topic/post which mentioned the mirror being dimmed because they had fitted a dash-cam beside the mirror and it was blocking the sensor behind the mirror, so it possibly though it was dark or getting dark. Have you done anything similar ?
1.5 TSI DSG R-Line MY19 Indium Grey, rear view camera, park assist.
Ordered 22/06/18
Built w/c 25/03/19 :(
With dealer 13/05/19 :P
Collected 20/05/19 :D

User avatar
twist
Posts: 1501
Joined: Sun Mar 17, 2019 7:38 pm

Re: Rear view mirror potentially faulty

Post by twist » Fri Jul 12, 2019 7:31 pm

Impala wrote:
Fri Jul 12, 2019 7:07 pm
Hi Twist.

Just wondering if you have made any progress with this.

Also, I came across another topic/post which mentioned the mirror being dimmed because they had fitted a dash-cam beside the mirror and it was blocking the sensor behind the mirror, so it possibly though it was dark or getting dark. Have you done anything similar ?
I think it was actually just what was previously suggested: it’s a little dim anyway but appears much dimmer due to the back window being tinted. I sat in the passenger seat and noticed the reflection of the driver window was pretty much normal.

I think the main thing is that it’s a bit narrower than the one in my Golf and I had positioned it so all I could see was out the back window. The window tinting gave the illusion that the whole mirror was dimmed.

Long story short: I’m an idiot and it’s working fine :lol:
UK 1.5 DSG R-line in Indium Grey
Keyless, park assist, rear view cam, driver assist pack plus, lumbar support
Ordered: 11/12/19 / Collected 20/03/20

Ian91
Posts: 161
Joined: Tue Oct 30, 2018 12:59 pm

Re: Rear view mirror potentially faulty

Post by Ian91 » Sat Jul 13, 2019 7:09 am

twist wrote:
Fri Jul 12, 2019 7:31 pm
Impala wrote:
Fri Jul 12, 2019 7:07 pm
Hi Twist.

Just wondering if you have made any progress with this.

Also, I came across another topic/post which mentioned the mirror being dimmed because they had fitted a dash-cam beside the mirror and it was blocking the sensor behind the mirror, so it possibly though it was dark or getting dark. Have you done anything similar ?
I think it was actually just what was previously suggested: it’s a little dim anyway but appears much dimmer due to the back window being tinted. I sat in the passenger seat and noticed the reflection of the driver window was pretty much normal.

I think the main thing is that it’s a bit narrower than the one in my Golf and I had positioned it so all I could see was out the back window. The window tinting gave the illusion that the whole mirror was dimmed.

Long story short: I’m an idiot and it’s working fine :lol:
Easy mistake, I did notice when I first sat in a T roc in the showroom that VW are using the old style rear view mirrors from the parts bin with a thick frame, on my Golf the rear view mirror is frameless.
Ordered R line 1.5tsi DSG Indium Grey 11/03/19
Built wk 34 and in transit 23/08/19
Arrived at the UK Port. 11/09/19
Due for collection 23/09/19

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