bbjoca wrote:

Boys, where did you get hold of the auto-dimming mirror? Any tips appreciated...

got my mirror... unclipped the old mirror....
no wiring !

it has the wiring for the sensors (light and rain) but nothing for the mirror !
they must have removed it for MY10 !

any ideas ?

How many connectors do you have there?
One or two?
There should be 2, one with 5 pins and one with 8 pins.
The one with 8 pins is for the mirror...

Thx for the reply Alex,
unfortunately i only have one connector which is connected to the light / rain sensors on the w/screen.
there is no other connector, and i see that my rearview mirror requires a square connector with 4 wires.

maybe they omitted this in the MY10 wiring loom ?
could it be that it's been hidden behind the roof panel (i did look by removing the light console... but there was nothing)

i am baffled...

Strange indeed....
BUT,
The four wires from the mirror are as follows:
- violet wire for ignition power (switched 12V)
- green-white wire for reverse connection.
- black-yellow for ground.
- white-green for humidity sensor.
Please confirm these colors.
Now, if you didn't have electrochromic mirror, then you don't have a HVAC with air quality/humidity sensing.
Also, the reverse connection is for invalidating the dimming when reversing for maximum visibility.
So, if you can live without these above, you'll only need to connect the switched power, the violet and black-yellow wires.
So, connect those with the following wires on existing connector:
- mirror violet wire with the blue wire in the existing connector.
- mirror black-yellow with the black-yellow wire in the existing connector.
Beware, there is also a brown-yellow wire in the connector so pay big attention.
Or better, verify with a multimeter that the black-yellow wire in the connector is ground connection and the blue wire has switched 12V power.
That's all.

thx again for yr quick reply..

on the mirror there are 4 wires: yellow, black, white , blue (i uploaded a photo in my gallery)

I have the split dual A/C system but no humidity control (i don't have automatic recycle)

can't i connect the negative to the interior lights ?

Yeah, they changed colors...
But the positioning of the wires was kept.
If you look closely, the connector has 8 pins, but only 4 wires/positions are used: 1, 2, 3 and 6.
So, according with schematics:
Pin 1, white - switched 12V power
Pin 2, blue - reverse signal
Pin 3, black - ground (GND)
Pin 6, yellow - humidity sense.

Connect only the white and black wires to the wires from the existing connector (the one for rain sensor).
Did you looked at the rain sensor connector?
It should be a 5 pin connector with only 3 wires connected, at pins 1, 2 and 3.
Only pins 2 and 3 will be of importance:
Pin 2 (black-yellow) - ground (GND)
Pin 3 (blue) - switched 12V.
Please confirm.

i confirm 3 wires (see my gallery photos)
blue, brown & Black/yellow

so u suggest i splice the black/yellow and blue to connect them to black & white respectively of the mirror ?

won't it cause a fault on the CAN BUS ?


i really appreciate your help

p.s. i notice that the wires on the mirror are much thicker than the ones on the rain/light sensors

Yes, that is what I've suggested.

In your place I'll do the followings:
1. Power on the bench the mirror with 12V between black and white wires to see if the mirror works OK and it's not defective. Pay attention to the polarity.
2. Splice a little the rain sensor's black-yellow and blue wires .
3. With a continuity tester, I would check that the black-yellow is indeed GND.
4. If (3) checks, then, with a voltmeter, I would check to have +12V between black-yellow and blue when ignition is ON and 0V when ignition is OFF.
5. If (4) checks, then connect the two devices between one another, as said, and see if works OK.

In the original configuration/wiring diagram the mirror is powered by F4 fuse in CJB and the sensor by F1 fuse.
Both are 5 Amps rated fuses. Because the current consumption is much lower than 5 Amps, for both of them, I would leave the F1 fuse the same (5 Amps), even if now it has a new consumer (the mirror) on its rail.
Don't worry about the thickness of the wires. Indeed, the rain sensor has 0.5 cross section wires and the mirror 0.75.

Last edited by alex_pescaru on 24th Jul 2012 8:28 pm. Edited 2 times in total

I will try it tomorrow morning when there is light (its 9:30 pm here )
The mirror is new from LR.. So i domt think its faulty
Maybe i should take the gnd off the interior lights ? At least there would be less interference...
And then take the + off the sensors, as you suggest...

What do you think ?

Last edited by Donnus on 24th Jul 2012 8:28 pm. Edited 1 time in total

It could be done in that way too, of course.
And please double check all that you'll do, in order to not be sorry later.
As for the mirror, new or not, it's a good practice to test it on the bench first.
In that way you could also see its power consumption and lit it with a light torch to see if it works OK...

Last edited by alex_pescaru on 24th Jul 2012 8:33 pm. Edited 2 times in total

Once again thank you...
I will try it tomorrow?..
I will keep the same fuse...

I will post my results....

now i am baffled ... the rain / light sensors receive 12V (blue cable) even with the ignition off (blue cable and GND at door)

so this cable would not be ideal to use for the auto dimming mirror...

don't have any options left

Hmm...
Then take the switched 12V from the interior lights too (as you want with GND).
Brown-green cables are 12V.
Black-yellow cables are GND.
I have a vague recollection that the 12V is an one pin red connector with a brown-green wire in it and the GNDs (yes, they are two - one directly connected to body and one through a FET for that effect of slowly dimming the lights) are in a black 2 pin connector. The black-yellow wire is the one connected to the body and is of interest.

See that in appearance the 12V stays on continuously.
But no, it's switched through a battery saver relay in CJB and then passes the F17 fuse.
The battery saver relay cuts power after you lock the car, immediately or after a few minutes, I don't remember when... But it disconnects alright, otherwise it will drain the battery if you left/forgot the lights in the forced on position.

the odd thing, is that i was looking at the wiring diagram of the light / rain sensors... and theoretically the 12V should be switched via ignition.
I dont understand why it gave me 12v even though the key was out ...

i will try the interior lights



UPDATE
once again i have different colors (see the gallery photo)