[RLYSMRT]

Hello everyone,
I currently own a 451 with the rain sensing wiper feature with the puck on the windshield. With that, my car does not have the Auto headlight function. It is a pure with almost all of the possible options added. I was curios to see if anyone has tried or knows if I just replaced the stalk to one with the auto headlight function, I would have the auto headlight function. If not, I'll live. Thank you for any help regarding this question.


Regards
-RLY SMRT

 

[jwight]

Welcome to SCoA!

 

[valvestem]

Hello everyone,
I currently own a 451 with the rain sensing wiper feature with the puck on the windshield. With that, my car does not have the Auto headlight function. It is a pure with almost all of the possible options added. I was curios to see if anyone has tried or knows if I just replaced the stalk to one with the auto headlight function, I would have the auto headlight function. If not, I'll live. Thank you for any help regarding this question.


Regards
-RLY SMRT

I am not sure, but a little more stuff may need to be done. Try a search on the auto-lights, I remember reading about them to see if I even had them (I have the puck), but I don't, and still live

 

[RLYSMRT]

I am not sure, but a little more stuff may need to be done. Try a search on the auto-lights, I remember reading about them to see if I even had them (I have the puck), but I don't, and still live

I couldn't really find information on it. Maybe in the future if I see one at a junkyard I'll pull the stalk and try it. Not worth spending 60 dollars and it not working.

 

[jzchen]

When you pull one let us know. Looking at lighting wiring diagrams myself. If you're willing to run wires to your SAM, (at your own risk), I can help figure out what wires you might need....

 

[RLYSMRT]

When you pull one let us know. Looking at lighting wiring diagrams myself. If you're willing to run wires to your SAM, (at your own risk), I can help figure out what wires you might need....

I definitely will. I don't plan on doing any major modifications to the car until I rack up some miles. I bought it with only 20 miles about a month ago and have 1600 on it now.

 

[jzchen]

Still staring at the wiring diagrams. I decided to assemble them as they are multi-page, and that is very helpful. There is an auto lights input on the SAM 9-34. 0.75 mm (assuming mm) YERD (yellow with red stripe) from pin 1 on the combination switch. That is the only difference that I see around the switch area...

 

[ales]

Yo, I tried it all on European Smart 451 Dec 2007, Pure. The car had no wiring harness in place for a rain sensor.

I made my own wiring harness and hooked it up to SAM unit.

The rain sensor was activated through Mercedes Vediamo (you gotta teach the SAM unit the auto-lights function).

I went to a junkyard a few days ago to scavenger another 451 with a rain sensor, probably 2008, Passion. I put in my car the speedo with auto-lights function, even the central console (they have an auto-light sign on one of the buttons next to the fog lights). I swapped the stalk for one with AUTO written on it. I would like to stress that all the parts were taken out from the smart 451 with a rain sensor.

It still did not work… 😂😂😂😂😂😂😂

The car acts as having no auto-lights function. The rain sensor switches off the electricity for the pods and rev counter. Once you disconnect the rain sensor, the pods will come back up.

No idea if this is the software issue and what not.

Hello everyone,
I currently own a 451 with the rain sensing wiper feature with the puck on the windshield. With that, my car does not have the Auto headlight function. It is a pure with almost all of the possible options added. I was curios to see if anyone has tried or knows if I just replaced the stalk to one with the auto headlight function, I would have the auto headlight function. If not, I'll live. Thank you for any help regarding this question.


Regards
-RLY SMRT

 

[jzchen]

If you have Daytime Running Lights (DRL) it will not work with both functions. Disable it and please update us....

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[ales]

I disabled DRL with my key. Doesn’t work.

Any other ideas? 🤔

If you have Daytime Running Lights (DRL) it will not work with both functions. Disable it and please update us....

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[jzchen]

I disabled DRL with my key. Doesn’t work.

Any other ideas?

With DRL disabled/turned off, re-enable the auto lights function. (I had auto-lights). When @Huronlad tried to enable DRL with his star computer it would not, so maybe your auto lights was not enabled when you tried/DRL prevented it?

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[ales]

I’m gonna give it one more go on Monday. Me pal has Vediamo. We always activated DRL first and then the rain sensor. We are going to try to switch off DRL through Vediamo and then we will see what is going to happen to the rain sensor.

But when I’m thinking about it. It makes sense to switch DRL off. But I had no idea that those two functions cannot be combined. 🤔🙅‍♂️

Just tell me. You have Auto-lights. Is the rain sensor swiched on when the stalk is in the position 0? Or do you have to turn it into AUTO position? Are there any icons on instrment cluster while in AUTO?

Cheers

With DRL disabled/turned off, re-enable the auto lights function. (I had auto-lights). When @Huronlad tried to enable DRL with his star computer it would not, so maybe your auto lights was not enabled when you tried/DRL prevented it?

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[jzchen]

I no longer have my smart it was in an accident. BUT I am confident that the two can not coexist. The SAM can not support both for some reason, not enough CANBUS "lines" or something like that....

There were no special indicators but the headlight ON indicator did light up when the lights were on as if you turned them on manually. (If I recall correctly).

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[ales]

That entire thing with Lin Bus makes sense.

My instrument cluster shows yellow icon “fog lights.” I thought there was an “AUTO” icon lit up on instrment cluster, but that one came probably later on.

I will keep you guys posted. Otherwise here is all I did regarding rain sensor until now:

Rain/light sensor install/SAM control unit

I no longer have my smart it was in an accident. BUT I am confident that the two can not coexist. The SAM can not support both for some reason, not enough CANBUS "lines" or something like that....

There were no special indicators but the headlight ON indicator did light up when the lights were on as if you turned them on manually. (If I recall correctly).

Sent from my REVVL V+ 5G using Tapatalk

 

[ales]

Here is the latest update:

We tried to to swich off DRL in Vediamo. The rain sensor did not work.

The problem is that the rev counter and the pods always die when connected to the sam unit. 🤷‍♂️ This should not happen in the first place.

Is it possible that the wiring schemes are somehow incorrect? Any other ideas / suggestions? 💡

That entire thing with Lin Bus makes sense.

My instrument cluster shows yellow icon “fog lights.” I thought there was an “AUTO” icon lit up on instrment cluster, but that one came probably later on.

I will keep you guys posted. Otherwise here is all I did regarding rain sensor until now:

Rain/light sensor install/SAM control unit

 

[ales]

Finally, I think I figured it out!

Let me just stress out, I did not have rain/light sensor wiring harness in my car. If you have the harness above the done light, you are sorted. You just buy a few parts, plug them in, do a little bit of coding in Mercedes Vediamo and you have a rain/light sensor.

My car did not have the much needed harness in place. I have made my own, hooked it up to SAM and my dash pods died.

That’s because I was missing a relay! The relay is under the C sign on the picture below.

I have found it should serve to “heated mirrors and rear fog light”. I have heated mirrors and they work without this relay. Which means that the C relay is only and exclusively for the “rain / light sensor”.

My dash pods die every time, because of this missing relay. The SAM unit does not recognise the rain sensor and reports an error.

Now, you would think, easy peasy, but hold your horses! This relay is no easy plug in / out relay. It is a part of main wiring harness. Which means you can only get it from the junk yard or from a new main wiring harness, with a rain sensor... 😬😬😬

I mean I have retrofitted in my Smart an automatic shifter, heated seats, original subwoofer, new Hertz stereo incl. tweeters, but the rain sensor remains the hardest from all retrofits.

I mean this will eventually takes additional work and I’m not sure, if I’m going to carry on. But at least you guys know. 😉🤙

Here is the latest update:

We tried to to swich off DRL in Vediamo. The rain sensor did not work.

The problem is that the rev counter and the pods always die when connected to the sam unit. 🤷‍♂️ This should not happen in the first place.

Is it possible that the wiring schemes are somehow incorrect? Any other ideas / suggestions? 💡

 

[ales]

Hey guys! I have another update!

I found out that the part I'm missing regarding the rain/light sensor is a relay!

The number of the part is:
A0025421319 (pictures below)

Disclaimer! I believe this applies only to EURO version of Smart 451. The relays on the US version have different functions (switching on the tail lights).

Since the wiring schemes are wrong, I need to find out how is this relay connected to the main wiring harness.

Btw. DRL and Rain/Light sensor really cannot be activated at the same time as I discovered in German Service manual (the last picture).

Finally, I think I figured it out!

Let me just stress out, I did not have rain/light sensor wiring harness in my car. If you have the harness above the done light, you are sorted. You just buy a few parts, plug them in, do a little bit of coding in Mercedes Vediamo and you have a rain/light sensor.

My car did not have the much needed harness in place. I have made my own, hooked it up to SAM and my dash pods died.

That’s because I was missing a relay! The relay is under the C sign on the picture below.

View attachment 68913


I have found it should serve to “heated mirrors and rear fog light”. I have heated mirrors and they work without this relay. Which means that the C relay is only and exclusively for the “rain / light sensor”.

My dash pods die every time, because of this missing relay. The SAM unit does not recognise the rain sensor and reports an error.

Now, you would think, easy peasy, but hold your horses! This relay is no easy plug in / out relay. It is a part of main wiring harness. Which means you can only get it from the junk yard or from a new main wiring harness, with a rain sensor... 😬😬😬

I mean I have retrofitted in my Smart an automatic shifter, heated seats, original subwoofer, new Hertz stereo incl. tweeters, but the rain sensor remains the hardest from all retrofits.

I mean this will eventually takes additional work and I’m not sure, if I’m going to carry on. But at least you guys know. 😉🤙

 

[ales]

Another update!

This is the wiring of relay mentioned above (A0025421319). In the wiring diagrams it is confusingly called "Rear Fog Light Relay."

From now on, it should not be a big deal to retrofit rain/light sensor.

 

[jzchen]

There is a rear fog light available in certain countries. I believe the rear lights have yellow turn signals for those. I hoped to retrofit them into mine, when I had her...

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