Up there is the photo of my retrofit set. I gathered up all the parts, then noticed there is no wiring harness in my Smart 451 2007. Gave up, wanted to sell it. Nobody wanted to buy it and I eventually decided to proceed with the mod.
Because I had no wires in my Smart 451 laid down for rain sensor, I bought following Mercedes rain sensor wiring harness (W203 Rain Sensor Wiring Harness Roof OEM 2035409006 D92):
Here is the list of the items I needed:
The Signal Switcher (used) A451 545 0010 /004
The Rain Sensor (used) A451 900 12 01
The cover for the rain sensor (used) A 451 821 00 36
The wire cover for the rain sensor (bought in Mercedes Dealership, unpacked) A 451 820 00 69
The Rain Sensor Sticking Pad (new, unpacked) - from AliExpress
Dead Dash Pods
I disconnected the rain sensor. Dash Pods came back again including the rev counter. The wiring diagram from Evilotuion is not correct (they have it the other way around). At the beginning I was paying attention to the colours of wires (same colours should go together - well it does not work that way).
Rain sensor wiring:
Red yellow cable (also the power cable) goes to N11-9 slot 14 --> this explains why the power is connected to Dash Pods. They come up only when you twist the stalk in "AUTO"position and therefore it activates rain sensor.
Violet blue cable (rain sensor's signal cable) goes to N11-2 slot 1 --> this should be LIN B! On Evilotion is the wiring the other way around. Anyway, this is the cable for additional instruments such as rain sensor.
Brown Earth cable (I guess it could go anywhere with other earth cables).
I spoke to my dealer and next week I we will try it to hook up on Star Diagnostics and activate it as mentioned above a.k.a. DRL funciton as we could not find a "rain sensor" in the diagnostics scheme on the first go.
Fingers crossed. 🤞