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So my car was at the shop getting the transmission rebuilt for the last 3 weeks and of course it was there during the huge storm we had… the owner of the shop said that it didn’t get a lot of water in it but it must’ve gotten enough to get under the seats. The first hint was the fact the driver’s side seat wouldn’t go back and forth. The Mercedes tech they had checked it out said it had to do with the motor that controlled the forward /backwards movements getting water in it. The tech fixed that. The car was completely detailed and the carpet was removed. With that said the transmission is fixed but now I have an issue with the ac/heat. At first the blower motor was running even with the car off. I removed the blower and installed a new resistor. Now the blower motor won’t turn on at all.. I checked under both front seats and it’s evident that water got underneath them. Now I know there was a member on benzworld and here that had the same issue because he bought a flood car.. with that said any help would be great. Attached is the codes I am getting. The car is being dropped off tomorrow back to the transmission place for their Mercedes tech to check it out… the car has sentimental value and too long of a story but I need to fix it. Any help would be great
Under floor of font seat, there a LIN bus bar and LIN bus power supply and probably they are water damaged, in addition in this area there are also a motors for B pilar air vent, you need to check for water damage as well.
Note I had the same issue with the climate control blower going after the car was turned off- it was the front SAM. Attached is a picture of a assembly located at the pillar floor on both sides of cabin. They have a small plug in connector, both connections likely have corrosion. Shame these connections were not cleaned while the carpet is out. To get to these connections requires the front seats and front carpet removal.
Note I had the same issue with the climate control blower going after the car was turned off- it was the front SAM. Attached is a picture of a assembly located at the pillar floor on both sides of cabin. They have a small plug in connector, both connections likely have corrosion. Shame these connections were not cleaned while the carpet is out. To get to these connections requires the front seats and front carpet removal.
those definitely got wet.. so you replaced them both and all was good? From what I gather those parts have the actuators in them? Which front Sam are you talking about? If you could point out which one that would?
yes the two ducts have small motors in them. You can buy a set used on Ebay for under $100.
I suggest simply cleaning the bus connections under the carpet, and be prepared to replace those ac ducts. I sense the blow motor resistor may not of been replaced properly, that is why the motor is not working. Be prepared to replace the front SAM.
If you W221 is a 2010-2013 this is the most popular SAM
10-13 Mercedes W221 S550 CL550 Front SAM Fuse Box Control Module 2219006001 OEM
Thank you for the detailed response… I actually picked up a whole set of actuators …
I got them for cheap… front Sam is actually been tested in working order.. also replacing the pedal just for piece of mind.
So here is where I am at to this point. I cleaned all the can bus lin strips on the driver/passenger sides.. I literally took each plug out of the lin bus strip cleaned them with electric cleaner and put them back. What I noticed is that you were correct in saying the b-pillar vents motors are probably water damaged as I don't feel any air coming out of either the driver's side /passenger's side B pillar vents. So I need to place the motors. The odd thing is that there is air coming out of the floor vents under the front two seats. The other issue I noticed is that no air comes out of the center vents on the dashboard which are directly above the climate controls. With this all said the air conditioner seems to not be blowing cold air but the heat works perfectly fine and I actually let the car run with the heat on to dry up some of the excess moisture. The last issue is when I scan the car with my icarsoft obd scanner I get the only 2 codes now and unfortunately the blower motor still runs when the car is off. I know its not the resistor cause I replaced it 2 days ago with an oem one. With all this said above do you think that the motors in the air duct are causing the center dashboard vents not to open and also to keep the blower motor to continue to stay on even after the car is off. Can you think of anything else I might be missing? I bought all the actuators as a set from ebay for $37.. they are used but as long as they work I am fine with it. My car has 170k miles and is super clean along with having the S65 amg kit on it. I bought in the thread as well of the actuators I bought I am guess that's the correct ones based on parts numbers I got
I ordered a dehumidifier three days ago with that exact idea in mind. I also removed the front two seats and removed the carpet. Got access to the air ducts under the two front seats where water definitely damaged components. The actuators for the left/right b pillar vents was water logged and full of corrosion. My friend who works at Ray catena Mercedes told me to clean all the electric connections with brake cleaner. With the carpets out I was able to clean all the connectors that were visible. Also the carpets were left in direct sunlight to dry. Hopefully I get the actuators this weekend and I am able to put the car back together. Then I will hook up the star to make sure it’s all good. Thank you everyone who posted here. I love this car and hope to have it back in running order shortly.
All is good with the ac. As someone said I needed to use star to normalize the actuators. The only actuator that’s an issue now is the one under the dashboard on the driver’s side. I have 9 actuators left from the ones I bought from eBay. Attached is the picture that I took of the error I got from star.
Clb0099, did you ever figure out the root cause of the water penetration? There’s articles on the forum about the windshield and cowl drains becoming clogged with debris and filling up to overflow conditions during heavy rains. You may want to check your drain tubes, mine were full of junk but after cleaning they free flow.