C230 Rain Sensor 1998
 

Just bought a 1998 C230 in real nice condition but high miles (133K). Just put a new center/drag link in last night and drives much better now. That was fun. I would like to install the rain sensor since the original owner did not get that option. I have studied the wiring diagrams and it appears all I would have to do is get the sensor and plug it into the CAN connector for it which is on the same board/module as the sunroof controls. I imagine that the CAN computer would have to then have that option enabled. Does anyone have any info on whether this definitely can or cannot be done. The dealers I have talked to recommend, of course, that I should just buy a new car... I have been told by one dealer parts desk that I can buy the rain sensor module for 120.00 PN 2108205710. Not sure if that is all I would need. Any help would be appreciated.

Thanks,
Mike

Mike
I believe it uses a different windshield due to the sensor, might want to research that too....
Gilly

My glass guys says that. He has two different windscreens, one for rain sensor cars and one for non-sensor cars. The one for the rain sensor equipped vehicles is slightly more.

Yeah, that section the sensor goes up against looks different, like a dark blue look to it, I know how the sensor works but it was never explained why the glass is like that in that area.
Gilly

Thanks everyone for the info. I was also quoted 362.00 for a new windshield with the rain sensor. So, if I get that, then can anyone address the rest of the job? Do I need a different trim piece around the rearview mirror? I looked at a 2005 C230 at the dealer that had the rain sensor and it looked like a plastic module glued onto/behind the glass that went up and joined to the trim around the mirror mount at the headliner. And also, the electrical question remains. Can I just plug it in and go? Would really appreciate it if there are any Mercedes techs out there who can tell me for sure before I throw a lot of money into it. I really want that rain sensor!!

Thanks,
Mike

I'd be worried that the Combination Control Module would be different. I didn't think the rain sensor was on the CAN, I thought it was hardwired to the CCM. At any rate I'd ask if the part number is different if it has the rainsensor system or not.

Gilly

AllData says this "The rain sensor consists of an IR transmitter and receiver and an electronic circuit for evaluation and communication via the CAN bus." Also, it is pretty clear from the wiring diagrams that it plugs into the board for the sunroof buttons and on this board the CAN bus connections are shown. I saw some info that seemed to show that a lens of some kind is glued to the windshield and everything mounts to this. So it looks like I would need: The special windshield, the rain sensor and the cover/trim for it. Then the last question is still: If I plug it in can it work?

Mike

That is the question! I don't have the answer, but I would ask about what happens to the five-second delay currently "programmed" into the intermittant circuit? With the rain sensor, you can leave the wipers on that "first" setting all the time and then the wiper only comes on when it rains.

Honestly, this seems like a whole ton of bother for something that is easily accomplished by simply rotating the stalk end switch, or pushing the stalk in for a single sweep. I personally have never pined for the rain sensor, even after using it on loaner cars. But, if you're just looking for projects, I guess it could be fun...

I am in Seattle which might explain my preoccupation with the rain sensor! I agree, that considering I would have to change out the windshield, this looks like a pretty big effort for little return. I would still like to find a way around the windshield issue. As far as the electronics end, I have been in electronics for 15 years and I sell all the type of parts that are inside doing the work such as CPU's and CAN controllers etc. So I have a high cojnfidence factor in that stuff. I feel that it isn't a great leap of faith that I could plug it in and it would either recognize it automatically or that I would need to get a config "bit" set. But I do not have specific training in automotive electronics. I am still hoping that there is someone out there who can answer some of these questions. I feel that if I worked for a dealer and had access to their info, that the answer would be pretty easy to find.

I believe the sensor is plugged into the dome lamp assembly, which is on the CAN. I'd try finding out if the cars with rainsensor have a different dome lamp assembly, I'd also look into the other thing I mentioned, the Combination Control Module, and the wiper switch itself.
The info I have on 129 and 140 chassis say the windshield sensor reports direstly to the CCM, but I don't think I have info on your car specifically.

Gilly