Rain/Light Sensor Retrofit

[ATB88]

Hi all, I picked up a rain/light sensor with the IR light filter as well as a v4.5 LCM that I would like to retrofit into my 2002 that didn't come with auto headlights/wipers.

The one thing I'm not sure how to deal with is that the windshields of cars that came from the factory with auto lights/wipers have this kind of black film deposited on the glass in the area where the rearview mirror's clamshell would enclose, with a cutout where you would stick the RLS to the windshield. Pic attached. Also, is that little dot cutout to the lower left of the main RLS cutout imortant, if so why?

My windshield doesn't have the black film, so I'm wondering how if this black film is there purely for cosmetic purposes, or if it is essential to the proper function of the RLS (keeps too much light from getting into the clamshelled part of the windshield and eventually into the RLS through the sides?). I bought some black vinyl window film from home depot to make my own solution, but it turns out that the film I bought isn't opaque, so, if it's important for function then I'll have to source something that is opaque. But I won't bother otherwise.

Thanks!

[ChipperM3]

You may have to wire to the sensor as well, but not sure. I had the rain sensor already so that part was plug and play. There’s a thread on the other e46 forum that looks to be exactly what you want. The member details how to DIY the RLS to a car not optioned with it. A quick search gets you to it.

[terra]

I think it's there mostly for cosmetic purposes, but it might also help prevent stray light from reaching the sensor.

[nextelbuddy]

have you performed the actual wiring retrofit? i was unaware there were M3s that didnt have the RLS... i know early m3s came with just Rain sensor and then later M3s received the RLS rain light sensor. do you have the RLS/Rain sensor plug in the car already just hanging? maybe someone replaced your windshield in the past and used a non M coupe windshield that didnt have the rain sensor?


in any event if you truly dont have the rain sensor wiring then you will have to run 4 wires to the GM5 module.

ignition, ground, Kbus and wiper input.

then you have to add the black overlay shroud.

on some glass its silk screen printed to the glass from the glass manufacture and some other glass its embedded between the layers.

for my Sedan i had to order the NO RAIN sensor version of the infrared windshield because the infrared version was NLA in germany.

i had to get creative so i took a picture of the rain sensor black shroud area and had my sister in law put together a design based on my photo in adobe illustrator along with measurements i have her. I then had my brother print me with black matte vinyl a replacement shroud.

then i ordered a replacement Rain sensor GEL PAD online and sourced the purple prism as well.

[terra]

have you performed the actual wiring retrofit? i was unaware there were M3s that didnt have the RLS... i know early m3s came with just Rain sensor and then later M3s received the RLS rain light sensor. do you have the RLS/Rain sensor plug in the car already just hanging? maybe someone replaced your windshield in the past and used a non M coupe windshield that didnt have the rain sensor?


in any event if you truly dont have the rain sensor wiring then you will have to run 4 wires to the GM5 module.

ignition, ground, Kbus and wiper input.

then you have to add the black overlay shroud.

on some glass its silk screen printed to the glass from the glass manufacture and some other glass its embedded between the layers.

for my Sedan i had to order the NO RAIN sensor version of the infrared windshield because the infrared version was NLA in germany.

i had to get creative so i took a picture of the rain sensor black shroud area and had my sister in law put together a design based on my photo in adobe illustrator along with measurements i have her. I then had my brother print me with black matte vinyl a replacement shroud.

then i ordered a replacement Rain sensor GEL PAD online and sourced the purple prism as well.

Rain sensor / RLS was a part of the premium package until MY2004 when it became standard (in the US - in other countries except maybe Canada, it was always optional)

That vinyl shroud could be something people would be willing to pay money for - especially if the same pattern is used on E39s / E38s.