2nd S Flooded This week! S Owners Keep your Drains Clean!!!
I have done a search for PSE pumps on the W220 forum and this seems to control the air vacuum for the Close Assist door and boot features and not lights etc?
I am confused...
These are from under the rear passenger seat, currently out of the car drying out in my garage.
I shall replace them this weekend after cleaning the conenctors etc as recommended on here.
Thanks in advance
I removed the grey square component which is attached to it's metal frame housing still, along with a small white clear plastic box, all connectors removed and left in car.
This grey square component has connectors for heated seats and one going to the CAN?
There are also a couple of boxes attached to the underside of the metal frame.
Picture below, please can someone name these components and what they do :-
Attachment 145589
I also removed this part which I think is the rear SAM and took it apart from the rear fuse box (which is left in the car with the 2 million wires).
Picture below, please can someone confirm this component and what it does (hope the lights as mentioned before)
Attachment 145590
And finally this small solid metal looking component with BOSCH labelled on it, this was the most wet and the connectors were dripping when I removed it.
Picture below, please can someone name this component and what is does :
Attachment 145588
I have left all the wiring in the car along with the rear fuse box, to dry away from the base of the seat area and left lots of absorbant towelling to get any remaining water and to hopefully dry out some of the wet wiring.
If drying these out does not work, at least I know I can change the part if need be, but which one of the above components does the lights related to, paticurlarly the registration lights?
I have been told the rear SAM which I think is the part I detached from under the rear fuse box in the second picture?
Thanks in advance.
the second picture is deffinitly the rear SAM and that is what should be affecting your lights, i am not sure what the other components are to i will try to look in my w220 and see if i can figure it out ill let you know as soon as i do. also if you say the component is as wet as you say it is, then i will probably need to be replaced.
The Best of Mercedes & AMG
Did not realize this could be such an issue so when I refilled my washer fluid two days ago, noticed the impacted leaves sitting right there at ground zero. Cleaned it out right away.

Its clearly described that the EMERGENCY drain belongs to the SIDE, a little below the air intake.
Gee, now i know why you folks over there are having so much problems with your cars...

Cheers, Frank
Well I took a good look at the car this past weekend (Saturday's weather was dry for the morning!!).
I looked at what would be obvious causes for my water ingress into the rear seat area. I first looked under the bonnet (raised into service level height) to follow what happens to the water from the windsheild and bonnet etc when going through the grated area at the top of the bonnet.
It all collects into a large plastic dish which spans across the grated area to catch the water. If the car is flat or leaning towards the passenger side (UK) then all water will flow into the large reservoir tank with the problematic rubber drain plug thing at the bottom. (Mine was blocked 3 years ago and flooded the front of the car which seems to be common). This was clear and has been since.
I then tested what would happen if the car is parked so that it leans the other way (drivers side - UK) and found that the large reservoir tank becomes redundant and the water goes towards the other side of the large plastic dish area. The design has a small rubber outlet to stop overfilling of this large plastic dish item, but with the car parked leaning towards the drivers side, this too becomes redundant.
I removed this large plastic dish item to get a better look.
Then it hit me, the drivers corner within the engine (UK driver side) is where all of this water will be directed and so upon looking closely with a torch, this area was choc full of leaves and mush (broken down leaves/dirt & sludge), and created a kind of small reservoir itself.
"This can't be good and must be the problem" I thought to myself. I vacuumed as much as I could and scraped out the crap which a long screwdriver, paper towelling, fingers etc and then vacuumed again. This area has the windscreen washer pipes running from the engine area to the washers themselves and so had to pull the pipes away slightly to get to this area.
I then retested and no more water collecting. It now runs straight out of the front drivers (UK) wheel arch area through a drain hole and some also came out of the rear drivers (UK) wheel arch area through a drain hole, so hopefully this is it.
I checked the rear seat area with all electronics and no water came through
I checked again yesterday and all good bar a small amount of water trickle which seems to be coming from the wiring tunnel from the front of the car to the rear (i.e. where the water is getting into the rear seat area from) which I am hoping is merely the water left from within this tunnel from before my fix and not fresh.
I am now planning to use a mains powered dehumidifier inside the car to draw off the remaining water/moisture as the weather sucks in the UK about now until April. Can someone recommend do I close all windows when this dehumidifer is on, what percentage setting should I use and I guess I will know when it has done it's job as no more water will collect?
Sorry if the above goes on a bit, but I am thrilled that I (hopefully) have found the culprit for my very frustrating water ingress problem.
p.s. It rained all day yesterday and was parked in the position that caused the water problem beforehand and all was good (apart from the small trickle which hopefully is what I said above).
RC
Your mechanic guy maybe just refering to the well known water collection tank drain plug that is designed to collect rain water from the windshield/bonnet area and dump it under the car through the engine bay area.
This was not my problem of late, the area concerned was other the other side of the engine bay area in the corner, check for leaves and old mushy broken down leaves/dirt in this area. Shine a torch to check. It didn't look obvious that there was a problem at first...
Apologies if you did mean this and not just the original drain plug.
Thanks.
I found three inches of water under the back seat, flooding the SAM unit, entering through that wiring conduit. After I mopped up and dried the unit everything, amazingly, is back to normal. The rear carpets are sopping though and I'm struggling to find out where the leak is.
Last year the air intake under the bonnet (hood) was cleared out and I have no leaves in there, it's draining fine. I have been advised to check the drains in the sills as they get blocked and the sunroof also drains to these.
Is it only the known air intake problem that floods the S-Class (2001) or are there other 'drains getting clogged up' issues..?
Does anyone know how to check these 'sill' drains? as I'm struggling to find them without getting fairly major i.e. taking seats out etc.
Any help gratefully received...
Adrian
I found three inches of water under the back seat, flooding the SAM unit, entering through that wiring conduit. After I mopped up and dried the unit everything, amazingly, is back to normal. The rear carpets are sopping though and I'm struggling to find out where the leak is.
Last year the air intake under the bonnet (hood) was cleared out and I have no leaves in there, it's draining fine. I have been advised to check the drains in the sills as they get blocked and the sunroof also drains to these.
Is it only the known air intake problem that floods the S-Class (2001) or are there other 'drains getting clogged up' issues..?
Does anyone know how to check these 'sill' drains? as I'm struggling to find them without getting fairly major i.e. taking seats out etc.
Any help gratefully received...
Adrian
Although I have not heard of this yet on an S-Class, my '78 450 SL leaked like a sieve until I found that the windshield seal was completely gone on the bottom and 1/3 of the way up the "A" pillars. One could easily see the windshield bow out when pushing on it from the inside.
Last edited by Skylaw; Sep 23, 2009 at 10:08 PM.
I checked the drain holes either end of the sills and found that the one on the driver's side (UK) just behind the front wheel was blocked. I took the plastic sill cover off and about two cupfulls of dried mud came out.
Having cleared this, and tested it by pouring water into the sun-roof surround, they are now fine and the car's dry.
I live on a steep hill and usually park the car nose up which I'm sure exacerbated the problem. In my experience, leaking vehicles and hills go hand in hand.

The lowest outside part of the car between the front and back wheel is a plastic colour-coded sill cover. At each end of this are two drain holes, about 3mm in diameter and angled back towards the read of the car. I shoved a wooden kebab skewer up each one and found the front offside one blocked.
Inside the front wheel arch, near the bottom, there's a 10mm bolt attaching the front end of the sill cover. If you undo this then the sill is just held on with a number of black plastic push-fit gromit-like things (the ones where the centre of them moves independently of the outside). Pull these off (by pulling out the middle 'core' first) and the plastic sill cover comes away. That's where I found two cupfulls of mud and dirt, blocking the drain.
Hope this makes sense!
Adrian
Last edited by AdrianMac; Oct 1, 2009 at 11:26 AM.






But as you said one in each corner.