CaliBenzDriver

Hands-on thread dedicated to all the forum spirits that make this place lively and inspiring

Back in 2014 before delivery of my W212, we used to go out for dinner on weekends with a friend who was driving an old 300kMi Lexus SUV. His steering wheel went up/down in/out super smoothly everytime he opened his driver door. Quiet like a hummingbird!

By contrast my new W212 steering wheel motions sounded clunky and laborious. I thought, it is brand new top of the line German goodness, it will get better - Well it did not.

Two years later, I eventually found a TSB publication to fix that exact known problem of clunky convenience entry. Great finally MB was going to make this screwed up feature work well.

When I picked up my car, I could smell a sprayed lubricant evaporating but nothing better happened. More clunky than day-1.

By that time the electric steering recall had replaced my new rack with a refurbed unit. My car was no longer tracking straight, dealer wheel alignment did not help. Basic sunroof had to be fixed 3 times... I really woke up to appreciate my experience of "the best or nothing" at face value. I simply turned off inconvenient features.

Fast forward some time, extended warranty expired and I really started "deconstructing Harry" to make things perform.
Most systems in these cars are carefully designed with embedded details that require service or else progress gently into a failure mode. Lack of lubrication is an old favorite. When you combine that with improper adjustments you get todays topic: a clunky telescopic steering column.


> Here Is The Meat:
Extracting the column takes about 40 to 60mn. Working on it takes from 1 to 5 hours.
Reinstalling everything home 90mn.

You could do this in place without removal but I don't suggest you go that route. By removing the column you get to try the adjustments you're making - You want to have full confidence that when reassembled the column will work the way you have tested it. You don't want to get on the road to figure out how your column is acting while driving.


basic common tools


pivots screws


plastic actuator in screw


steering surrounding's


rear view


bottom spline


actuator motor


measuring preset position....


No ESL here!


the whole enchilada: passenger side


front view


driver side view


first step: Hex-10 ... wheel is out!


pivot shaft are brital steel. Lube bearing area


slider guide pin


steering column top ball bearing: seriously DRY


measuring preset position for reference


guiding parts: LOOK AT **** MACHINING


screw slide: UNDERSIZED HOLDER


adjusting soft slider SMASHED BEARING!


right sizing catch surface: test fit...


telescopic column slide is mostly smooth


column side parallel alignment


> Practically:
-- The column itself is ALL RIGHT 👍

-- The two kludges that got strapped on the column to move X+Y articulations are the only problem here. They are inadequately assembled. No amount of spraying or greasing can fix that.
German engineers would do well to copy the old designs they licensed to Japan 20 years back, it worked perfectly!


> To Do List:
Study for yourself the X-Y actuators shortcomings.
One is a screw, the other a steel cable spinning a captured bolt between bearings.

​​​​​​Once you're able to emulate the actuator by hand, the motion will be smooth when the DC motor operates it.
Right now you can hardly move anything by hand! Don't go overboard, I am not saying you want everything LOOSE, nop! You want the motion to spin smoothly by hand. Once you start adjusting things, you'll get a definite feel for happy middle. Doing this PROVIDES NO FREEPLAY whatsover to the steering wheel.
The motors force needed and the steering column freeplay are hardly related , good German design!

> Position References:
-- The steering column position is learned by the controller (F-SAM?). When you reassemble everything, you want to have everything back in the same spot.
-- Use your scanner to set the steering column on 0° before pulling things apart.
-- Drop the column and then measure the XY positions for reference (caliper pics above)


> My Notes:
It's gonna be as good and as safe as you make it. Don't mess with it unless you know what you know and what you don't.

> Old Scuba Wisdom:
No one is responsible for your own gear and ultimately none of your actions.​​​​​
It's fun but it's not a game!

CaliBenzDriver

This debugging is separate from post #1: declunking the steering column - While your steering is out on the bench, I suggest you PLAN ahead and take the opportunity to work on more items with quick access.

Save your time, you won't like bouncing the column out a second and third time to work on the following items :

1. Ignition switch module !
2. Steering Column Modules stack
3. ESLock module if you have one
4. HVAC driver side actuators
5. HVAC Temp sensor
6. Steering wheel buttons
7. Steering stalk levers
8. ....

The first 3 VIP Modules in bold really could use attention to prevent show-stoppers. The others will manifest themselves more gently.


> Simple Steering Miracle:
Facelift cars use an electric steering rack. One good thing that sets it apart from previous racks is it consumes data to control it. The rack knows when the column is centered on zero degree, it then tries to camp on center based on speed bias.

When that works, it drastically helps drive straight. When upset the car acts as if over a barel with open toe-out.

Same car with a soldered Steering Control Module: day and night, a pleasure to drive like a tank.
What I'm saying is if your electric steering car is all over the hwy, fix the steering COLUMN Module.

Enjoy your Benz

S-Prihadi

I once disabled easy entry for like a year, and the up-down motor get kinda stuck.
Use my hand to help and its okey.
Now I able the easy entry so the parts get excercised.
This is good info Cali on which components we must pay attention to.

I am lucky that my car steering is super straight and not tiring to drive at high speed pass 100 MPH.

Thanks

pierrejoliat

Mine also has gotten stuck in the down position two or three times in the last eight years, like Surya, I helped it along then it works fine for a year or two, now I lower it to the lowest setting, then hit the up button quickly to get t up a minute amount and set the memory there instead of all the way down. hasn't happened since.

CaliBenzDriver

> Fixing things up... How-To:
Now that we've looked at the whole column hardware let's focus on preventing XY mechanism from getting stuck.
The column axes are super well built and operate nice and smoothly. That's in contrast with the rotating screws mechanisms that provide motion. Two radicaly different quality grades from two different companies.


1 -- SLIDER In/Out :
Number one offender is the the telescoping slider. It is tasked with extending the column 5" appart.


Slider In/Out: pivot A + pivot B
​​​​The issue is pivots point A and B are captured tight so the telescoping actuator screw can not stay parallel to the column as it extends/retracts. The results is it jams itself into a nasty wedge. The dry plastic gearing does not fair well in these extreme conditions.

> Pivot A :
It literally uses a rolled pin instead of a shaft. That's a real china design. All that pin wants to do is grab on something, instead of smooth rotation!

> Pivots B - Rough Bearings!
Look at this manufactured beauty ...

stamped steel
It doesn't matter how much grease you add to that joint, it's gonna grab the plastic slider and prevent it from rotating normally.
Grab your set of files and make these ("pivot B") bearings smooth.
There are two sliding plastic nuts and each has two of these stamped joint that need to allow rotation. It will take you sometime to file and test fit until you reach the satisfaction of a nearly smooth joint.


2 -- TILT Up/Down :
You guessed it, this motion tilts your wheel up/down. It almost works well.
​​​​​​

Tilt Up/Down: pivot A + pivot B
Both pivots A and B are captured tight. They need to be allowed smooth motion.

When you play with the column by hand you get the feel for what the limitations are.
Think of it as brake caliper slides. They are loose to allow the caliper to self-center over the disk to squeeze pads, right?
Here pivots A/B need to be free to allow self-centering of axis.

> Pivot A is smashed:
This is an internal ball bearing plus a tie-down post. Both are as good as glued
Tilt Pivot A nuts and tie-down post
As is the input drive cable can hardly be rotated by the tiny motor. All the energy is spent overcoming the tightness of the smashed bearings.
-- Hold Nut-1 and adjust Nut-2 so cable can be rotated without pining the ***** into their soft plastic race.
-- The tie-down shaft at 90° must be able to slide in/out and rotate to locate itself dynamically where it wants to be aligned.
-- "Tilt Pivot B" has the same issue as "slide Pivot B". File it smooth.

> Drive motors and screws slides :
the two DC motors use a worm gear to ultimately spin a 1/2" screw that locate a plastic slider.
Last step is to grease the whole thing to your geart content once you get everything well reworked.

> Disabled !?
Guys, you can't vote "smooth and quiet" when you have this feature disabled because it got stuck

BenzV12

What a job, I would not bother that but I appreciate what you did

CaliBenzDriver

Welcome! I am glad I could fulfill the mechanical curiosity in some of us. I am sure you've tackled projects tougher than this

It was a bit overwhelming at first to figure what was wrong. Once I understood how it worked, I explored the limits and it became simple.

My real motivation to drop my column out was to work on my solderless Ignition Switch and Steering Lock... I discovered the Steering Column Module and Steering Wheel Modules...

ESL foam plug

Zynthe

Sorry but im a semi new owner. I havent noticed my wheel move up/down when it starts/stops, is there a setting for this? I have a 2011 E550.

CaliBenzDriver

Check through your IC menu if you have the option to de/activate "convenience entry"...

Check your column actuators are working. They are used to move the column proactively during COLLISION events.
I've experienced my driver Seat + Column move at high speed to protect me during rear end collision!

GrepAwk

I appreciated reading this. Nice pictures.

CaliBenzDriver

We are a group of individuals who like to extend self-help and hate fluff or generic non-sense.

I am glad you found this thread insightful.


​​​​@GrepAwk ... small world !
I too used to earn my living in part with both "Grep & Awk" powerful string cmds - My -vi is a bit rusted.
I've been formatted: linear logic still my friend👏

pierrejoliat

This is super helpful Cali, I may pull the lower cover and at least see if I can loosen those two bolts on "Pivot B" with the column in the car, its working again right at the moment and I still have easy entry enabled.

ygmn

Got any info, tips & pics on how to remove column?

Good write up on issues and solutions.

now the question is whats up with the MB "BEst or Nothing" engineers allow design of mechanical joints to be like this?
They are not the best they can be for sure.

For now mine is fine moves smooth and quietly - but if made like this only time and movement "mileage" will wear it to a clunker.

Thanks!

CaliBenzDriver

My favorite way to work is to fix all the issues built around the steering colum at once. I don't like piece meal jobs that create duplicate work.


Removing the TILT A + B + C fasteners

Ok, I heard you about simple, so hear is my : "3-Screws TILT FIX"

Tilting motion is produced by the cable actuator located towards passenger.
Go ahead and remove the nut-A and 2 screws-B. This will allow you to slide the cable out fron its tilt motor. It just comes rigtht out.

On the bench:
Once you have that piece on the bench, you can see how hard the cable doesn't want to rotate. The bearing mis-adjustment cause it to bind.
Also the plastic nut needs to pivot in the rough metal rings... file the surfaces smooth!

Also it may be posible to save even more time by working in the cramped space under the dashboard... this position is not in the Kamasutra.

BenzV12

If there's supermassive black holes floating the universe, this thread is also a superinformassive one
Great work