RNS-E and heated mirrors doubts.

miguel_e38

miguel_e38

Member
Hi,

I am the owner of an Audi A2 1.4 75 from 2004, BHC. And what a great car and a great forum!. I am planning to retrofit heated mirrors. From what I have read, our cars come with pre-installation. Today I just confirmed it in my own car. But, before buy the mirrors from the dealer I have a question. The mirrors are heated only with the rear heated windscreen button or there are other situations? I have read in this forum people saying that the heated mirrors are activated below +5 ºC, but other saying that it is not true. Could someone tell me if this is true? From my point of view if heated mirrors are only activated with the heated rear window is not very useful. At least, where I live. Also the mirrors are heated with the wipers?

I am also planning to retrofit RNS-E. I retrofitted in my car BOSE, rear parking sensors, MFSW from a A6 C5 and more little things. I want to know if I can activate the option OPS (Optical Parking System) with MK1 RNS-E or I need MK2 RNS-E. Or maybe in our cars the option simply can't work. I have the next PDC control unit: 8Z0919283A (the last one according ETKA).

Regards.
 
I didn’t think mine heated mirrors as the glass doesn’t have the little heated symbol on it (do only French cars do this?)
Last week was cold and mirrors were frozen.
On day 2 of the big freeze I pressed the 2 window de-icing buttons and the mirrors defrosted to!
 
Phil FSI said:
I didn’t think mine heated mirrors as the glass doesn’t have the little heated symbol on it (do only French cars do this?)
Last week was cold and mirrors were frozen.
On day 2 of the big freeze I pressed the 2 window de-icing buttons and the mirrors defrosted to!
Click to expand...
So, if the external temp in you case was below +5 ºC. It will confirm that the heated mirrors only works activating the rear heated windscreen. ?
I have another car (1999 BMW E38 730d) and the mirrors are heated partially between +25 ºC and -10 ºC, and fully below -10 ºC or with the signal from rain sensor and I find the heated mirrors very useful. I want to retrofit this function in the A2, but if only works with the rear heated windscreen I will not spend the money in the heated mirrors.
 
I retro fitted heated mirrors and they only work in conjunction with the heated rear screen.
It's possible that cars with the factory fit winter pack may work differently. The pack includes heated washer jets which should activate automatically below a threshold temp (+5 degC or so) and logically this could also trigger the heated mirrors without the need to operate the rear screen

Anyone with the winter pack who could confirm this ?????

Cheers Spike
 
Two of mine have the winter pack, and the mirrors come on with the rear screen only. I don't know on what basis the heated washer jets activate, I just know I've not had the washers not work due to being frozen - that said I don't remember having driven in any really cold weather where they might.
 
Proghound said:
Two of mine have the winter pack, and the mirrors come on with the rear screen only. I don't know on what basis the heated washer jets activate, I just know I've not had the washers not work due to being frozen - that said I don't remember having driven in any really cold weather where they might.
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Heated washer jets are activated as soon as you turn the ignition on. They are feed directly from a fuse.
 
I have the winterpack and the mirrors heat with the rear screen heater, but I dont know about the +5 limit since I only use them when it is ice on them
 
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As far as I know, the only heating device that's dependent upon outside air temperature is the Webasto auxiliary heater. The wing mirrors are heated in conjunction with the rear screen demister, and the heated washer jets are ignition-switched, meaning they're on whenever the car is in use, irrespective of season.

There are a number of people on the A2-related facebook groups who assume that whatever applies to other contemporaneous VAG vehicles also applies to the A2. I believe that's where the 'below 5 degrees' rumours started.

The heated wing mirrors are triggered via the CAN bus. A digital 'switch on' signal is sent from the climate control unit to the door control modules, which in turn send electrical current through the mirror glass. As such, getting the wing mirrors to heat according to alternate conditions would either require a simulation of the appropriate CAN message, or it would require the electrical current that heats the mirrors to be delivered by something other than the door control modules.

Cheers,

Tom
 
I think Tom has pretty much cleared things up re the heated mirrors.....however, on page 75 of the owners manual the only mention about the heated mirrors states.
"The mirror surfaces are heated when the ignition is on (depending on the outside temperature )
 
johnyfartbox said:
"The mirror surfaces are heated when the ignition is on (depending on the outside temperature )
Click to expand...
If that's the case, those of us with heated mirrors would find that the mirrors clear on their own, without any driver input. I've never noticed this happening, so I suspect the owner's manual is incorrect ...which it is in numerous other places. However, I'm happy to be proved wrong. Finding out the truth, even if it undermines what you previously believed, is better than believing yourself to be right when you're not!

Where did we collectively get the information that the rear screen demister also operates the wing mirror heating? Is that also in the owner's manual somewhere, or in the depths of ElsaWIN?

Cheers,

Tom
 
Timmus is right (as far I know). In fact the signal to trigger the heated mirrors travels from the climate control unit, to the confort module and then to the door modules. (Nevertheless is the same CAN bus, in the three cases, I don't know why not trigger the door modules from the climate control unit). But I just check my owners manual and it confirms what johnyfartbox sais. Maybe the owners manual is wrong? Very extrange.
Also, the confort module must be codec for "climate control unit". What happens if the car has the manual control climate unit and heated mirrors? The confort module never will trigger the door modules to activate the heated mirrors?
 
miguel_e38 said:
Also, the confort module must be codec for "climate control unit". What happens if the car has the manual control climate unit and heated mirrors? The confort module never will trigger the door modules to activate the heated mirrors?
Click to expand...
Don't cars with manual heating controls still have the rear screen demister button?, so perhaps this feeds the comfort module which in turn signals to the door control module to power the mirrors.
 
Hmm, I Will try to NOT press the rear screen heat Button tomorrow and ser whats happening ? I know my oem Mirror glass had small thermo sensors on them and the new non OEM had not..could they be on Always then? I Will investigate
 
Zacharias said:
Hmm, I Will try to NOT press the rear screen heat Button tomorrow and ser whats happening ? I know my oem Mirror glass had small thermo sensors on them and the new non OEM had not..could they be on Always then? I Will investigate
Click to expand...
Could you do the test, Zacharias?
 
Just performed a little test (video to follow shortly)

The car was off and temp about 9DegC
Start car and do nothing else and the temp still hovers at 9DegC
Switch on rear demister and temp increases to 22DegC+

Fairly conclusive. :)
 
My contemporary (in systems terms) '03 A6 heats the mirrors whenever necessary when it is on. My '04 A2 (as well as the '52 I have also fitted with heated mirrors) only do so when you hit the rear screen button after it is running and don't beforehand. I assume my 02 would if they were fitted. In conclusion, I concur with Tom @timmus - they're only on when they're switched on.
 
I allso checked this yesterday when it finaly got Cold again, and as you said, nothing untill I hit the rear demist Button, when I did the ice went away in about 20 seconds and started to dry the mirror.

But I wounder if the Bi metal switches on the OEM glass was shuting down the heat when warm or Keep them from starting IF above 5deg...

My new non OEM Mirror glas does not have those
 
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So, I think we must conclude that the user manual is wrong and the only form to start the heated mirrors is pressing the rear demister button. It's a pity that this little big car don't have the option to automatically starts the heated mirrors despite of have the electronics to do that.

Thanks a lot to you guys for this investigation.
 
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