bachree

Hi Everyone,
The rain sensing wipers on my vehicle are not stopping to work when in auto mode (the first two stages on the stalk) and i am having to keep it at 0 to keep it from working. This issue started one morning and has been going on since then. It has been a few months and there is no obstruction around the sensor area (i believe it is around rearview mirror) and the windshield is clean. Is there anyone out there with a similar issue? If it is the sensor, is there a manual that shows how to change it out and what would be the part number? Is there any programming/calibration involved with changing out the sensor?

Arrie

Your windshield is clean but make sure that the small rectangular shaped window in the black upper strip of the windshield does not have any kind of film on it.

bachree

That box is checked

Arrie

Then, take the plastic cowl off and see that the sensor is in place correctly.

In my car the cowl comes off just prying it down. I need to move my mirror a little bit but it comes off easily. Then you can see the rain sensor and check it is in place correctly. If it is then the problem is either the sensor went bad or the control module went bad. If sensor issue you may need to have the windshield replaced as some sensors on cars come with windshield and cannot be replaced without new glass. But I'm not sure about this on your car.

bachree

This is where the sensor is at. It doesn't look like it's built in to the windshield. I also checked the fuses 10-13 and 17. They're intact.

konigstiger

Best to have someone pull fault codes may simply need to be re-initiated, if steadfast in DIY part replacement, current # is 2049014504. Any problems after install may need startup, line 8 in attachment.

bachree

Thanks a lot for the help.

I've purchased the 4504 part number and installed it without problems the old part is 2048708826. After installation the rain sensing wipers worked properly but "autolamp function inoperative" error showed up and auto headlights stopped working and always stayed on. I tried the procedure in


Without success. At the end I installed my old part back and regained auto lamp function and lost the auto wipers back.

Now trying to figure out what the problem is. My theory is that the part number 4504 may not be the correct part for cars equipped with adaptive high beam headlights (P2 package)

What is your opinion?

konigstiger

Delete.

konigstiger

New part # matches old part, in accordance with sheet posted above, have someone perform initial startup using MB Xentry (diagnostics).

omarmit

I have this exact same issue. How did you fix it?

omarmit

i have this exact same issue. How did you fix it

bachree

Never bothered to fix it since the car is driven less than 3000 miles a year. Living without auto wipers. My next step would be to install the part that I have purchased and take it to an independent mercedes mechanic to ask if it is a part that needs to be paired to the car to function properly.

CaliBenzDriver

For what it's worth this sensor is built with unsoldered pins that can simply be repaired under 30mn with a solder iron.
No need fancy programming, an iCarSoft scanner will come in handy to read codes.
👍

bachree

I revisited this issue and installed the new sensor as described in my previous message. I do have an icarsoft mb V3.0 reader. Are you speaking based on specific experience or you just made an assumption about reading the codes? I can't find any module relevant to this issue going through the icarsoft menus.

CaliBenzDriver

A while back I decided to eliminate glitches by class type instead of faults one by one.

I've delt with this particular module and neighbooring humidity sensor and rear view mirror strictly on a hardware basis.

If your scanner is not showing this module as standalone, have a look under the OCP for data.

bachree

I was able to find it under "Driver - side SAM - Front Signal Acquisition And Actuation module(N10/1)" with the following error: "The light Sensor Has A Malfunction. Calibration is Missing".

Error comes back instantly if I attempt to remove it. There is no calibration option for it but while playing around with other menus "autolamp function inoperative" error on dashboard disappeared and now the windshield is not continuously working on auto mode. I have splashed water on it while stationary and it is not wiping...

Spraying water from windshield wash nozzles triggers the wiping action. We will see what is next. I may live with it if the dashboard error does not come back, auto lamps work and then get the calibration done next time I visit the shop which is has been only once a year in a long time knock on wood...

CaliBenzDriver

​​​​​​You're saying you replaced the rain sensor and cleared related F-SAM code but wipers still don't sense auto rain.
Unlike your HL that work properly with same daylight sensor.

This split results are a bit strange... Try to Reboot the car to give F-SAM a chance to behave...

bachree

Exactly. The same error popped back up after clearing it and for some reason the behavior of the car changed. I only drove it a quarter mile afterwards so I agree it may need some time.

I will leave it alone for a week and drive it as is. Hopefully I get a chance to encounter rain and/or have an excuse to drive it at night.

Thanks for the quick response!

bachree

Happy Ending!!

I purchased the following device for $130 which allowed me to define the variant coding of the newly installed light sensor. Trickiest part was to select the right variant among all the options but luckily I got it down in the first try (maybe I did wrong but everything works as expected)




I tried icarsoft mb 3.0 Before this device which had pretty much 0 coding capabilities compared to this. Maybe it is capable for the main components such as engine, transmission. Etc but embarrassingly weak compared to the Launch device that I linked when it comes to the ancillary components.


Launch device has so many options to play with that I will probably spend hours on and possibly break something on the car in the process...


Bonus: the only other error in the car was about 0 calibration of my xenon lights that I replaced 4 years ago due to a failure and the launch device allowed me to check that box as well...

Also: it creates an email report such as following with a touch of a button

http://aitus.golo365.com/Home/Report...type/D/l/en-us