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Homelink Mirror Auto Dimming (or not?)

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by eglmainz, Aug 11, 2009.

  1. eglmainz

    eglmainz New Member

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    Homelink Mirror, does anyone else have issues with the Auto Dimming not happening enough? Mine only starts to dim when the car behind me is on my Arse. When they are a few car lengths back, I get the full glare of their headlights in my face. There is not an override button, or the ability to switch it dimmer. Yes, I have it powered on, as I have tried turning it off too, and that does not work either (Obviously).

    I have searched a few threads here, and noticed a few complaints mixed in with questions, but no one really answered... Is there a way to improve the 'Dim" factor in these mirrors?

    It seems to me that one possible cause of this is that the 'split' in the rear windows seems to often cast a shadow on the homelink mirror sensor area, so it does not 'see' the bright lights behind me, until the car is almost on me, say at a red light. Then, the mirror tends to dim very well, into a nice shade of green. Once I pull away a little bit from this car, the mirror will stop dimming, and I am blinded once again.

    Obviously, this issue with the homelink mirror will only affect some of the Prius out there, and not others. If you have a 'normal' mirror without the auto-dimming feature, then this is not the link for you. ;)
     
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  2. jay_man2

    jay_man2 jay_man_also

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    The few times I've experienced it, I wondered if the dimming was working. I was just thinking about this this morning, and while the hatch does limit rear visibility, that plastic strip across the back does serve to sometimes block headlights, which I like.

    But yes, I do think the mirror could/should darken quicker.
     
  3. tjp74

    tjp74 New Member

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    Same here. I thought it was broken and tried turning on and off few times. What to do? I find it worthless.
     
  4. scottwyden

    scottwyden new jersey photographer

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    I picked my 2010 up last night and noticed that it wasn't dimming very quick.. the dude with the bright headlights behind me was getting on my nerves ;)
     
  5. 32kcolors

    32kcolors Senior Member

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    Do you have a tinted film on top of the factory tinted glass?
     
  6. Judgeless

    Judgeless Senior Member

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    I think mine is broke. It does not make a difference if it’s on or off. I do not have tinted windows.
     
  7. eglmainz

    eglmainz New Member

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    No. Just factory tinted. I will be getting windows tinted soon, but have not had the time...

    I think that for me, at least, it is because the center 'bar' between the rear windows casts the shadow of the cars behind me, right across the little sensor on the mirror. when a car is very close me to me behind me, or a tall SUV, sometimes they are able to hit the sensor, and then the mirror dims nicely. It just seems to miss that for most normal cars on the road.
     
  8. Tideland Prius

    Tideland Prius Moderator of the North
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    Same issues we had on the Gen II. What we did was rotate the mirror upside down so that the light sensor is out of the line of sight of the rear spoiler and thus can detect the headlights.
     
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  9. jay_man2

    jay_man2 jay_man_also

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    After I spent the last 8 weeks getting used to the Homelink button in a new place, I'm reluctant to try that "fix." :p
     
  10. eglmainz

    eglmainz New Member

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    Did that fix the issue for you?

    Also, does that affect the wires that power it, as I would hate to rip those out and disable the garage link.
     
  11. Tideland Prius

    Tideland Prius Moderator of the North
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    Yup. I don't have a picture of it. When rotating the mirror, do watch the wires. Remember that the mirror is double-jointed so use that to your advantage when manouevring the mirror. You do not have to unplug anything. Just rotate and pay attention to the wires, that's all.

    lol. I don't know how the buttons are arranged on the new mirror but the old mirror, I use the middle button so upside down, it's the still the middle button lol.
     
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  12. jay_man2

    jay_man2 jay_man_also

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    I use the middle button too, but if my finger slips I don't mash a big old greasy print into the mirror glass. :eek:
     
  13. dogfriend

    dogfriend Human - Animal Hybrid

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    Another trick that I learned on John 1701A's website:

    Put a piece of translucent material over the sensor. John used a piece of colored plastic like you might find on a report cover ( he used blue color). I used a piece of Kapton tape (yellow in color) because I had it handy at work. This helps to kick in the dimming at higher light levels.

    [​IMG]
     
  14. ny biker

    ny biker Member

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    I think my mirror works great -- better than any regular rear-view mirror I've dealt with while driving at night.

    Why would some work well and some not?
     
  15. ceric

    ceric New Member

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    I know that mine does not work as well as those on my BMW and Mazda CX9 (also from Gentex). The difference is quite obvious. I just never bother to track it down. The autodimming works by comparing the two sensors (front and back). Put a tape on the front-facing sensor certainly will enhance the difference, therefore, work well.
     
  16. dogfriend

    dogfriend Human - Animal Hybrid

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    This might also be a function of where you drive at night - in my case, the street lighting and oncoming traffic headlights (I think) fool the mirror into thinking it is daytime instead of nighttime.
     
  17. dsviv

    dsviv Member

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    I was wondering if it was only me. My auto dim doesn't work when a semi is directly behind me with its lights blinding me, but yet works as soon as I open the garage door to the bright sunlight. Like you, the system is on, so that shouldn't be a factor.

    I would have never thought to turn the mirror upside down. I have suspected that the center bar may have had something to do with the problem, but it sounded too simple for a car that is so technical.
     
  18. gil

    gil Junior Member

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    I had the same problem with our 05 and I firmly believe it is due to the spoiler bar blocking the light the sensor would normally "see". I haven't driven the 2010 at night yet, but will try to do this in the next few days (my wife's car). My 07 Camry Hybrid has the auto-dim mirror and it works fine.
     
  19. nmrickie

    nmrickie Member

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    I tried moving the mirror upside down, but it would not adjust high enough to see out the back window.
     
  20. jeffcrilly

    jeffcrilly New Member

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    It is _definitely_ the bar on hatch blocking the sensor. I can see a "shadow" of the bar right on the sensor.

    I did figure out that it compares the diff in light of the two sensors - one on back and one on front. This is stupid since the one facing front will be illuminated by oncoming car headlights.

    I also tried rotating the mirror... It DOES NOT fit "upside down"... The case is too thick... It would only work if I was abut 5 feet tall.

    Can I just TAKE IT OUT and replace it with the old school manual "flip" mirror?

    Whoever engineered this mirror really blew it. probably not an engineer but someone in marketing trying to be clever ! (I cannot beleive how much I paid for something that doesn't work.)

    really. Driving at night with this setup really sux

    Toyota should do a recall on this mirror and replace it with one that has a sensor near the top... Like the USA-built GENERAL MOTORS cars!