S-Class (W221) 2007-2013: S 320 CDI, S 350, S 450, S 500, S 550, S 420 CDI, S 600

electrohydraulic pump repair instead of replace?

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Old Oct 9, 2018 | 01:36 AM
  #1  
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From: Toronto
2003 s430 4m
electrohydraulic pump repair instead of replace?

2010 S450 4matic VIN: WDDNF8EB6AA297998

Photos below:

The skinny: could someone please help out with removing/ attempting to repair/ or replace and reinstall the w221 eletrohydraulic pump - any advice welcome

The details:
Some time recently i started getting quite the light show the dashboard, all malfunctions would appear, all dials would bounce around, all various dash symbols would come on and off
(shown in this YT video linked below)
I had it diagnosed at MB and they said there was a faulty wheel speed sensor however the source of all the problems was the electrodydraulic power steering pump.
I had the speed sensor replaced at a local indy since that was a cheap repair and I was hoping that it was indeed the sensor causing this electrical madness and not the $2000 pump.
That repair did not change much, and very shortly afterwards, the power steering was completely gone and this time there was only one message on the dash: 'Power Steering Malfunction See Oper. Manual' (btw I could not find such a malfunction in the owners book)
So I leave the car with some clever mechanic who is known for electrical magic stuff.
He gives me a call a day later and says the car is ready and working but no guarantees. Apparently he did some cleaning of the pump but nothing extensive. He further stated that a more thorough repair may be completed via removing the pump and sending it to some locals for soldering work inside the unit. I would have chosen this option from the start however I never got a call about options, just one saying to pick it up. Normally I'd be tough on any shop in this situation but I've been weak on confrontation recently.. where are my *****?! I paid the labor and took the car. (Even with the later fix, it's still a gamble)
Enjoyed driving for about a month when the light show came back, then went away for a little while, then one morning (after a spirited drive the night before (coincidence?(probably not))) the pump got the shakes, I would get the single msg: Power Steering, however this time I could hear and feel vibrations coming from where the the pump is located (right behind the front bumper cover, lower passenger corner.
I refuse to bite the bullet on a new pump! Not yet
I removed the skid plate, and wheel splash guard and tested to confirm. I pulled the green wire dedicated to power steering from the X30/30 chassis CAN/FFS voltage distributor (located behind the front passenger foot well.
When plugged in and car on, the pump vibrates bad, when unplugged no vibs.
So now the car is sitting as pictured and I am wondering about fixing and or removing/ replacing the pump myself.
Any-who I am wondering if anyone has any know how. Specific removal/ reinstall steps, bumper cover will probably need to come off. I'm guessing there may be hydraulic fluid that may need to be drained?
Making a last effort before replacing. Maybe it is something else that is causing the the problem. I've read about the wheel speed sensors doing weird things the the rest of the w221/w220
Over 2 years of enjoying this fine ride and this is the first real issue that I've faced.
Got it at 92,000 km, currently 125,000 km on the clock.
Thanks for reading, any feedback is appreciated!

( shown in this video:
)


location

there is an open hole on the side?..

bottom view

looks shady



Last edited by danielkon; Dec 21, 2019 at 05:50 PM.
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Old Oct 16, 2018 | 03:47 PM
  #2  
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Old Nov 1, 2018 | 07:58 PM
  #3  
danielkon's Avatar
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2003 s430 4m
Thanks for the info Konigstiger, much appreciation! I have gained access to the previously worked on motherboard. Upon opening the bottom, a whole bunch of white powder fell from somewhere above the board, maybe a pump burned itself? Looks bad... (photos below) I have decided to just replace it and hope that no damage has been done to the rack. Unfortunately based on the installation procedure provided I have determined that this job is beyond me so to the shop it goes.



can see some burned pins, notice the how the housing is rimmed with the powder, oh man..

those wires connecting the board to the machine look compromised (and worked on)

more powder on the floor
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Old Dec 21, 2019 | 04:03 AM
  #4  
Roman Savelyev's Avatar
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2010 S450
Im not even joking, I am having THE EXACT same problem. Im on my second pump in the last 8 months :-). Mind letting me know any other info you have found? Because to me it sounds like an electrical issue. No friggin way a pump messes up TWICE in the span of less than a year. Thank you.
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Old Dec 21, 2019 | 05:52 PM
  #5  
danielkon's Avatar
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2003 s430 4m
Are you sure the pump was replaced? Maybe it was just fixed instead and the mechanic gave you the wise guy special. Or maybe it was replaced with a used one?
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Old Dec 21, 2019 | 07:44 PM
  #6  
Roman Savelyev's Avatar
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2010 S450
Originally Posted by danielkon
Are you sure the pump was replaced? Maybe it was just fixed instead and the mechanic gave you the wise guy special. Or maybe it was replaced with a used one?
saw your youtube channel! Wanted to find out some information. My second pump was remanufactured, and I do the work myself. So I ordered it online kinda thing. Actually have the same car as you.
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Old Dec 22, 2019 | 12:06 AM
  #7  
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2003 s430 4m
Nice! So you have the same light show on the dash? Hows the car treated you otherwise?
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Old Dec 22, 2019 | 12:22 AM
  #8  
Roman Savelyev's Avatar
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2010 S450
Originally Posted by danielkon
Nice! So you have the same light show on the dash? Hows the car treated you otherwise?
yeah had the same ABS thing at first. Light show is just ridiculous. Thank god got it in the garage before the tranny shut off. Just wanted to ask if you got a new pump or not, and whether or not the problem came back. Other than that the car treats me amazing. Literally anything else feels like a downgrade.

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Old Dec 22, 2019 | 12:50 AM
  #9  
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2003 s430 4m
Had it replaced with a new unit (or it may have been remanufactured) shortly after making the post. So far so good. Where did you get your remanufactured unit from?

Anything else IS a downgrade.
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Old Dec 22, 2019 | 01:53 AM
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2010 S450
Originally Posted by danielkon
Had it replaced with a new unit (or it may have been remanufactured) shortly after making the post. So far so good. Where did you get your remanufactured unit from?

Anything else IS a downgrade.
honestly forgot. It was some shop on ebay. This was march of this year. The pump also made a bit of a squeaking noise when you turn the steering wheel, as if low on fluid. Problem was that the S class has like 3 diff variants of those pumps with different power connectors. Had to buy a different plug that fit the pump. Almost thinking maybe it was getting overloaded, and as a result burned out again. Mind sharing where you got your pump from? You’re in Oakville right? Im in Kitchener, so if you got it locally for a decent price...
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Old Dec 22, 2019 | 02:30 PM
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2010 S450
so heres the gig. The system is poorly sealed in both the plugs as well as the seal around. Had moisture getting inside. Sh*tty buzz is that the cold weather and hot pump thats above the logic board creates the condensation. Let the car dry for a couple days, and all the problems went away. So I'm going to clean the board, reseal it properly, seal the connections, and put a moisture pack inside. As my friends called it, russian tuning ;,).


Bit of corrosion on the logic plug

Condensation inside
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Old Dec 22, 2019 | 10:21 PM
  #12  
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2003 s430 4m
Man nice catch! Now I feel the need to check the seals on mine. BTW the place that did the work for me is J&JW Team.
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Old Dec 22, 2019 | 10:46 PM
  #13  
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How much was the service?
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Old Dec 23, 2019 | 04:13 PM
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2010 S550 Black on Black
I just had that pump replaced 3 weeks ago. It cost me $1825 inc. installation at an indi shop I use. The tech told me that these pumps have had different replacement versions through the years. He ordered the latest version and it needed an adaptor cable to make it work. It also has to be electronically matched to the car's ECU using the STAR/Xentry system. Not something easy to do DIY. I'd be scared to go with a used one. I now have a new pump with a 2 yr warranty.
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Old Jul 23, 2021 | 01:02 PM
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2012mercedes s550
Unhappy 2012 s550 COUGH ON FIRE RIGHT AT THE PS PUMP

CAR STEERING SUNDENLY GOT HARD AND CAUGH ON FIRE.. CA IS PERFECT 23K MILES...ANYONE HAVE ANY IDEAS HOW THI HAPPEN.






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Old Jul 23, 2021 | 01:43 PM
  #16  
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Originally Posted by PALMBEACHPERFOR
CAR STEERING SUNDENLY GOT HARD AND CAUGH ON FIRE.. CA IS PERFECT 23K MILES...ANYONE HAVE ANY IDEAS HOW THI HAPPEN.







Shoot me a message. You have private messages disabled. You had an extreme case of what I had.
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Old Jul 23, 2021 | 01:54 PM
  #17  
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Hi I am new here. dont know how to enable messages.

Call me 561-908-3441
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Old Jul 27, 2021 | 02:14 PM
  #18  
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Call me 561-908-3441
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Old Jul 27, 2021 | 02:30 PM
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Palm Beachperfor: This seems very rare. Beyond your insurance, and this forum, have you reported this to others? My opinion is, I think MBUSA would be mildly interested. But other "higher" authorities, like National Transportation Board. They handle recalls, testing, enforcement. Keep us posted on outcome and good luck.
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Old Sep 24, 2022 | 12:28 AM
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Originally Posted by danielkon
Thanks for the info Konigstiger, much appreciation! I have gained access to the previously worked on motherboard. Upon opening the bottom, a whole bunch of white powder fell from somewhere above the board, maybe a pump burned itself? Looks bad... (photos below) I have decided to just replace it and hope that no damage has been done to the rack. Unfortunately based on the installation procedure provided I have determined that this job is beyond me so to the shop it goes.



can see some burned pins, notice the how the housing is rimmed with the powder, oh man..

those wires connecting the board to the machine look compromised (and worked on)

more powder on the floor


Most of the problem for internal faults is from driver unit and resistors, replace and problem can be solved.
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