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how to turn off auto dimming rear view mirror?

7.6K views 25 replies 15 participants last post by  bouncerMk4  
#1 ·
any ideas how i do this? sorry only owned the car for a week!
 
#5 ·
God knows why you'd want to. The standard ones are utter cack. My advice would be not to remove the really useful optional extras in your car.

You have 3 options.

1. Swap the 192 wash wipe relay for a 377 one. This wil also disable headlight washers and autowipers if you have them.
2. disconnect the wiring above the mirror (you can access the connectors when you remove the dome light). There are 2 of them. 1 for the rain sensor and 1 for the autodimming function.
3. replace the windscreen for a non-rain sensing bracket version and attach a standard mirror to the standard base fitting on the glass. Then you can choose whether or not to remove the wiring loom for it or not. You'll also loose the auto wipers function if you choose to do it this way.
 
#12 ·
thanks for the reply chaps. The reason i dont like the dimmed rear view mirror is that its bery hard to see what type of car is behind me. Theres a little sensor on the front of the mirror which when i cover up with my finger doesnt seem to make any difference. I am thinking about getting my windows tinted again and am worried that the rear view mirror will still dim and make it impossible to see out the back at all!
 
#15 ·
Yes, from what I can remember there is a little button underneath the mirror, when "enabled" a green light is shown at the bottom of the mirror, press the button in and the green light goes out.
 
#17 ·
Not unless it came out of a Passat. I've sold about 15-20 autodimming mirrors and none had a button (except the one I did take of a passat).

The sensor on the front is only half the function. The sensor in the back of the mirror facing out the window also reads the light level and compares the 2. If you put your finger on the rear sensor and let light get to the one on the mirror side it'll dim.

Honestly, just take out the dome light and disconnect the wiring. All you have to do is pull the plug out. It's a simple fix and takes about 2 minutes.
 
#18 ·
thanks for the reply chaps. The reason i dont like the dimmed rear view mirror is that its bery hard to see what type of car is behind me. Theres a little sensor on the front of the mirror which when i cover up with my finger doesnt seem to make any difference. I am thinking about getting my windows tinted again and am worried that the rear view mirror will still dim and make it impossible to see out the back at all!
Are you sure you know how these mirrors work because I can't follow your logic. You can see just as well as any other type of mirror in daylight so it doesn't matter if it's switched on or off. The only time the mirror's glare function works is when the car behind has it's headlights on.

Now if you're getting your rear windows tinted, that will reduce the glare, therefore there'll be no light getting to the mirror, therefore the anti-dazzle function won't work, therefore it won't make a blind bit of difference what type of rear view mirror you have.

The other point I can't underdstand is you say it's very hard to see what type of car is behind you. Well again the anti-dazzle mirror only works when the car behind has it's headlights on. You'll have a better chance of recognising it with the anti-glare function on because if you look at it thru a normal mirror you'll be blinded by it's headlights.
 
#20 ·
I too find that the auto-dimming mirror works very well.

My 2005 Bora has the little switch underneath the mirror and this will switch off the dimming function, or as Bazmcc has advised, simply unplug the wiring to it inside the interior light.
 
#24 ·
He wants to able to see if a Police car is following him I'm guessing or if that is a CHAV on the rear bumper cant think of other reasons to know anything about the vehicle or whether to put your foot down and knowing you might not have a chance to pull away or save the embarrasment.
 
#25 ·
ive seem to have opend a can of worms here. maybe there is a certain degree of wanted to know if a poice car is behind me :) (or at least be able to see an undercover cop in an unmarked car), primarily because i am driving with a heavy foot at the moment as the car is still new to me.

I dont have a button on the bottom of the mirror and i dont seem to have a sensor on the front of the mirror so maybe it has come out of another car?

I just would have assumed that if i covered the sensor on the front it would stop it being able to detect the light, but its not the end of the world i suppose, and i should leave it in there as it is another selling point if i decide to sell it in the future...
 
#26 ·
ive seem to have opend a can of worms here. maybe there is a certain degree of wanted to know if a poice car is behind me :) (or at least be able to see an undercover cop in an unmarked car), primarily because i am driving with a heavy foot at the moment as the car is still new to me.

I dont have a button on the bottom of the mirror and i dont seem to have a sensor on the front of the mirror so maybe it has come out of another car?

I just would have assumed that if i covered the sensor on the front it would stop it being able to detect the light, but its not the end of the world i suppose, and i should leave it in there as it is another selling point if i decide to sell it in the future...
we have it on the A3 but to be honest - it's just as easy to flip down the anti-glare flap on the "old" mirrors. As for wanting to know whose behind you - if you are not selling something illegal or a speeder why would you want to know - as long as you can see lights you know there is someone there!