Remote Mirror Switch internals and wiring diagram (5.2)

As part of my LED conversion I pulled apart the remote mirror switch today to have a look at the guts.
Its pretty easy to pull apart.., I use toothpicks so it doesn't damage the housing..

Just be careful you don't lose the tiny springs, shaft, and balls ( Lol )

The lighting in the switch consists of x2 halogen bulbs that pass light laterally through the clear plastic cage, plastic legs and then through a filter to the dial face. in other words.. There is no direct path for light to travel from the bulb to the dial face)

This is important to know when choosing the correct LED..
3mm LED's no matter how bright don't scatter the light ''horizontally enough'' to replicate the effect of the OEM halogens. and so will not work! You need ''side throw'' LED's

The light then passes through a filter just behind the dial face..
In Audi mirrors the filter is Red.. whilst the Ferrari mirror is of course green.
This will also interfere with the LED conversion.

Filter is removable by removing the dial face.. but I don't recommend it as it stress fatigues the plastic and repeated removal cycles may damage the interference fit.

Now on to the wiring..

Led's are polar, and extremely voltage sensitive..
So to do the conversion properly you need to trace out the circuitry and where to put the resistors..
I had no wiring diagram , but I could work out that Pin 2 is +ve and Pin 5 is -ve
I used a 9v battery just to be safe..

However when power is applied only one of the halogens light up..?!?
The other one is not blown as I tested its continuity with a voltmeter.

So what gives.. ? How does the other Halogen get its power to light up..?

Can anyone provide a wiring diagram for the switch or shed some light on the circuitry..?

Thanks in advance..








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Thanks for chiming in Ian..

The bulbs are soldered in are therefore non removeable ( unless by de-soldering)
The "?" goes to the springboard contact on the other side of the PCB ( see pointer in Photo)

The board is unmodified oem Ian.. I just can't test it in the car ATM as my dash is out and i dont want to throw an airbag light.

But in the car ( based on previous tries) both bulbs light up.. but on the bench only one lights up..?

All the other switches are easy to change LED.. however this one has me stumped..
I



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I continuity traced the Positive Pin 2.. and this is what I got at the solder at the base of the bulbs..
So Power is getting to both bulbs.. just no earth..?

The other contacts on either side of the bulbs did not test for continuity with Pin 2
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Some more tracing

The other side of the bulb that lights up goes to the
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Here is the contacts on the board as they trace out to Pin 2 + Pin 5 -ve

Ian.. AFAYK is there only one power supply to the switch..?

I know a wiring diagram exists somehwere on Fchat but I cant seen to find it..



Does Pin 2 power everything including the LED..?
If so putting resistors in may stop the switch working properly bc of too low voltage??
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Found out what was wrong.. Bulb was blown.. What an idiot I am..
Both bulbs should light up when Power /Earth are provided to Pin 2 and Pin 5
But thanks for the wiring diagram Ian, and for letting me know that Pin 2 is the only power source to the switch.

Gotta choose the right LED now.. Obviously I can't use low voltage LED's.. they will blow unless I put in resistors.. and that will drop the voltage to the switch and may e interfere with proper functioning of the mirror motors.

Need 12V LED with in built resistors.. and hope I i get lucky with the luminous intensity..

 

An Update..

The 'PCB tracts for the bulbs in the remote mirror switch can be transceted to allow for resistors to be put into place.
These resitors only drop the voltage to the LED's and not to the Mirror switch itself, so motor function operating voltage is not affected.
Here is a photo of the tracts and resistors pre and post modification..





View attachment 3708266 View attachment 3708267

 

Now I have another question for the 'gurus'..

Are the 360 ''missile switches'' the same internally as the F355 missile switches..?
In other words can we ''cannibalize'' parts from the F360 switch to ''resurrect" our F355 switches..
Specifically the white ''prongs'' and spring, housing and flip button..?

Below is a photo of the 360 hood and glovebox switches, and a F355 Door unlock switch


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