Recently my '06 E350 has been exhibiting some troubling symptoms. It started about 4-6 weeks ago just after I had the transmission fluid and filter changed, though I don't know if the two are related. The first thing that started happening was that it would become stuck in top gear after driving on the freeway for 5-10 miles. When exiting the freeway I found that it would not downshift either automatically or by trying to put it into manual shifting mode. What would correct the problem is simply turning the ignition off and then back on again. Around town it was never a problem, only after driving in top gear. This has probably happened a dozen times or so. A couple of weeks ago it escalated to becoming stuck in 3rd gear after accelerating from a stop or entering the freeway, for example. Again, coming to a stop, turning the ignition off and then restarting the engine corrected the problem. The next time it got stuck in 3rd the CEL was lit. After restarting it stayed on for about 15 miles and then went out. This happened one more time with the same results.

Today, on my way home from work I got on the freeway and found myself stuck in first or second gear ( the trans was in Sport mode). At 25 mph the engine was turning about 3,000 rpm so I'm thinking it was 2nd. This time the CEL was lit and restarting the engine had no effect at all. I had to drive home about 20 miles at this speed. I tried restarting a number of times as well as holding the shift lever to the left and right. I also could not switch from Sport to Comfort mode. The other thing I noticed was that when when shifting into reverse or drive it produced a very sharp, strong jolt when it engaged either gear. This was with the engine idling at about 800 rpm.

I'll be taking it into the shop as I think this is beyond my ability to fix but I'm hoping that someone here might have come across this or a similar trans problem and knows what the cause is.

Sorry to be so long-winded and I hope someone can enlighten me on this problem.

Thanks,

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Gary

1992 300E, 2006 E350 and 2006 C230 Sport

Pull codes if you have the ability. Otherwise have a shop do it. Likely a sensor issue, codes will help narrow it down.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

Was it a MB specific shop that did the work?

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Jim

Yes, it was an MB dealership.

Skippy - I don't have a way to pull the codes. I'm assuming a shop would do it as a first step in their trouble-shooting. Any idea what sensor would be responsible for something like this?

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Gary

1992 300E, 2006 E350 and 2006 C230 Sport

Just did a little Googleing and found a couple of similar problems where a low auxillary battery was the culprit. The symptoms were that the car was stuck in a low gear and the CEL was on (Limp Home mode?)

Found another where it was a damaged conductor plate ( don't even know what that is). Do either of these sound likely for my car?

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Gary

1992 300E, 2006 E350 and 2006 C230 Sport

You may (or may not) want to read this thread detailing with my experience with my wife's 2006 E350 wagon and its transmission. Note ILUVMILS's post closer to the end where he points out that it is possible to change just the conductor plate on the 722.9 in some cases. Not sure whether this is still a "dealer only" repair...

http://www.peachparts.com/shopforum/tech-help/307933-06-e350-722-9-transmission-sticks-1st.html

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Christopher
'06 Mercedes E350 station wagon (silver/black)
'85 Mercedes 300D (black pearl/palomino)
'85 Mercedes 300SD (smoke silver/burgundy)
'79 Cadillac Sedan DeVille

'05 Toyota Camry (because always running is nice)

'85 Mercedes 300D sold back to orig. owner 8-1-06
'84 Volvo 264GL Diesel, owned 2000-2013

Yes, I came across your post about an hour ago. Based on that I called the local MB dealership and asked about conductor plate repair on my car. The service writer (who seemed familiar with the problem) said that there is a new kit that has come out in the last year or so for replacing the conductor plate/TCU. I don't know if this is the same kit that ILUVMILS was referring to in Dec. 2011 or if this is an update to that kit. Either way it beats having to buy the whole valve body for big $$$$. I'll be taking the car in later today and see what they say.

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Gary

1992 300E, 2006 E350 and 2006 C230 Sport

Bumping this old thread with the 20/20 hindsight that comes from the passage of five years since the post and having just fixed this problem and done a YouTube video on the repair.

Yes, the 722.9's had a set of consistent problems, and resulted as usual in a class action suit when MB denied knowledge of any failure pattern (Mercedes named in class action lawsuit over defect in the 722.9 7G-Tronic automatic transmission | Got a Class Action?) but the problem of the transmissions shutting down the controller (with no Check Engine Light) was well established, and the cause was failed conductor plates, just like their 722.6 predecessor. It would have been an easy fix if MB hadn't *coded* the replacement plate (has to be coded in with a STAR machine), and refused to sell the parts over the counter or to independents, citing it as a "theft part" to get around Right to Repair laws, guaranteeing your only option was... pay the dealer the $2,500 to $3,500.

The market has adapted, and the situation has improved, and I am now living proof that...

1. There are many suppliers who will fix your actual bad conductor plate for $200 to $250 so no recoding is necessary
2. It takes just a messy half day to pull and replace the valve body and remove the plate (although the car is down while waiting for repair at the vendor)
3. You can clear the code with an Autel scanner

...because I did it and have the YouTube video to prove it...

https://youtu.be/gpkkEySV6ZE