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Conductor Plate Change Problem - Help Please?

22K views 21 replies 4 participants last post by  salman108 
#1 ·
Firstly thanks for all the information I have already gleaned from this forum.

USA 2006 S65 92k miles - owned for about 6 weeks - flawless in every way.
Routine oil and filter change about two weeks ago.
Decided to change the transmission fluid, filter and pan gasket along with check and replacement of the infamous adapter plug. Adapter plug was pretty clean.
All good until I replaced the adapter plug - had to fight it to get it to seat right and in the end the 7mm screw sheared in the conductor plate. Crap!!
It was not going to come out so I removed the valve body and ordered a new conductor plate. Following some good instructions and keeping everything surgically clean removed the old plate and replaced with a new one.
No issues and all good.
Fitted the valve body back into the gearbox - paid close attention to torque values. Replaced the pan and filled up with (Mercedes)fluid. Started the engine - added fluid at ambient until it showed on the dip stick. Allowed the car to reach operating temperature 80C and checked level again - all good.
As soon as tried to run the car through the gears i got a warning "dinging" and "return lever to park position" appeared on the instrument cluster. WTF! Sit down and run back through everything I have done.
Perhaps I did not get the "yellow" selector engaged when I put the valve body back. Drained the fluid and removed the pan. Lever was in the correct position.

Fired up the computer and started searching - nothing so far. One comment I did read said do not turn the valve body upside down. Well I did when I was cleaning so could this have upset some of the check valves?
Do I need to rest the computer or anything else that I am missing.

Help and advice please?
Roger
 
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#2 ·
The model tells me you have a 722.9 and not a 722.6 gearbox.
Thus
You can not just swap conductor plates without doing the appropriate coding.
The proper way to do it via SCN coding through an authentic computer, and remember to transfer all the adaptation data.

Cheaper way to do it is to contact some one who has STAR with offline coding enabled.
 
#5 ·
I am sorry I didn't pay enough attention .

You are right the S65s were supposed to retain the 722.6, as were the S600s.
However there are cases where that is not true.

As mentioned earlier, you need to follow the steps listed by @atmsmshr and find out for sure which transmission you have.

If there is a dipstick then it is 722.6, else it is 722.9. The problem you have listed points to 722.9.

If it is 722.6, you will need to check the codes and get back to us.
 
#4 ·
ROG,

Some online sources do indicate that your 2006 S65 uses the 722.9 (NAG 2) transmission. However, only the 722.6 (NAG 1) has the dipstick tube and adapter plug.

Review the photos in this thread - if your adapter plug looks similar, if the filter removed was oval, and the conductor plate looks the same - then you have the 722.6 transmission. (From your description, I am assuming that you have a 7226 (NAG 1) trans. For reference, there is no dipstick in my 2007 S550 722.9 transmission and I had to pump in the ATF after changing the filter.)

http://www.benzworld.org/forums/w220-s-class/1631656-transmission-service-diy-2.html

What kind of ATF did you use? 236.10, 236.12 or 236.14? If you used MB fluid, I am going to guess that it was 236.14. Factory filled ATF for your year was 236.10 - the MB bottled variety no longer comes in that spec - your replacement ATF was probably spec 236.14. Although it says "backwards compatable," the two fluids have big differences and may (probably) not mix well. If you only did a pan drop, only 3.5 L were swapped out with each pan drop.

The adapter plug - only a finger tight (4-Nm) torque is necessary for this or the brass bushing will strip out from the conductor plate - as you have discovered. (Just to verify - your original conductor plat brass bushing is in fact stripped out?) I usually try to seat these adapters with a firm push from my palm before trying to torque in.

If it were my car, I'd start from least to more expensive troubleshooting.
- What , if any, CEL is there? If none - then a limp home fault is not locked in. You should be safe with a car restart and cycle through the gears.
- Were there any problems during the relocation of the old conductor plate solenoids to the new one?
- Is the replacement conductor plate MB or a knockoff?
- Is the adapter plug fully seated?
- What type of ATF was used?
- Is cold ATF in band?
- Did the new filter click in and stay in place?
- Was the valve body dropped?

Mike
 
#6 ·
Mike thanks for chiming in
Confident my car has the 722.6 gearbox - identical to what is in my 2004 S55.
Fluid used Mercedes 001 989 68 03 13 ATF134 states 236.12 & 236.14. Backward compatible to 236.12. Same fluid I used on the S55 with zero issues.
Conductor Plate is OEM #140 270 11 61 not a knock of - I am a parts dealer so know the difference. Same part as sold by all the major European wholesalers. Confident of the source but I guess there could be an issue with the part itself. I will check warranty returns tomorrow.
Me being stupid resulted in the sheared screw - the sheared part was left in the threaded insert on the conductor plate with nothing protruding to allow extraction. Hence the conductor plate change. Reassembly of the 6 solenoids and plate change went smoothly with no issues at all - very straightforward. I treated the valve body with utmost care and apart from being turned over for inspection nothing untoward happened. Body was not dropped.
Filter - Mercedes original - clicked into place.
Adapter was very clean when removed and probably did not need replacing - no ATF present and no leaks - I know should of left it alone.

Today's action is to replace the valve body, filter, pan and fluid. I have a clone STAR diagnostic kit which I have not used in anger as yet. I will get it up and running on the car and see if it tells me anything and report back.

Thanks Roger
 
#9 ·
Good,
Keep your old conductor plate handy.

Once you have mastered the STAR ( some thing I have failed to do after several years ), you will notice there is one menu item, called initial startup in almost all subsections.

That menu item is specifically for transferring adaptation etc data from an old module to a new module.


I am afraid, I won't be able to help hence forth, and may require to enlist @Ex_Fed or Eric for help.

I have DAS simulation running on one of the VMs, let me see if I can get you the screen shots.
 
#11 ·
I Have been reading about different ATF fluids and issues with mixing due to only 3.5L being removed during a filter change. Logic tells me that mixing of fluids would not stop the GB working totally but could cause performance issues during normal operation. I plan to top up with what I have today - Mercedes fluid - to move forward but once - hopefully if I can get it working again - do a full flush as per Mikes write up.
 
#12 ·
Roger,

You definitely have a 722.6 from the photos.

If there is not a hard limp and CEL set, then prior to changing the valve body I would definitely give it another try to cycle through the gears and see if the warning abates.

Good Luck
 
#14 ·
Valve body back in and 10 x screws torqued to 8nm. Next the filter and pan.
Topped up with fluid and started the engine. Brought the level up to the 25C mark.

Tried to move the selector and got the same message - "move selector to park" - WTF!!!

OK I then remembered that I had seen that message before when I had accidentally pressed the "start" button on top of the shifter when changing gears.

So I had been starting the car using the "keyless Go" so I stopped the engine and started it with the key in the ignition. No messages when I moved the shifter - hallelujah!!!

Drove the car slowly to build up the temperature in the GB to 80C so I could complete the fill level check. Car drove fine and no issues with the gear change at all. Comfort, Sport and Manual all worked as they should.

Got the car back on the lift and checked the transmission pan for 80C and it was so. Lowered the car and stopped the engine. Started it with the "keyless go" and guess what the red message of death appeared again when I used the shifter. Stopped the engine and started it with the key in the ignition and no issues.

Top up the level with about .75 of a liter of fluid. Tried starting again in both ways and now no red message of impeding doom - all seemed good. Have been driving yesterday and today with no messages even though I use the "keyless go" to start the car.

I think I am in the clear and thanks for your support Mike & Salman 108.

Maybe the warning was telling me the car was low on transmission fluid - is that possible?
 
#15 ·
Good show in getting it sorted out!

Being low 0.75 L of ATF is a large delta. At the point of measurement on the dipstick tool - this region/horizontal slice in the transmission body is an annular space so a small amount of fluid change results in a large change in level. Therefore - being low in ATF could have been a contributor to the warning message.

Although none of these symptoms clearly fit your description, for future reference attached is a troubleshooting guide, courtesy of MAVA.
 

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#18 ·
Not sure I understand your car's symptoms. What is 'kicked up'?

Do you have a CEL?

Is the car drivable?

Any matches on the symptoms in the troubleshooting guide that I posted?
 
#20 ·
Ok - usual suspects.

ATF is low.
Adapter plug is leaking and wicking into the TCU.
ATF and filter never changed.
ATF changed with wrong specification.
One wheel speed sensor going bad. (needs STAR diagnosis)
Tires are not uniform.
 
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