you have the 722.9 so this is thread is for a different transmission

Hello. I have a c-class with automatic transmission 5g tronic for about 1 month and 200k km. When I change gear from 1 to 2, I feel as if someone is pushing me from behind. I changed the oil and the filter a few days ago but nothing has improved.
Reading this forum, I think there is a problem with the TCC solenoid and I ordered it.
Could it be something else?

I have the same symptoms and I have rebuild the transmission, but unfortunately the jerk was only more slightly. The jerk is still there.

Hello guys,
Anybody still have this problem?
A simple test, just active the speed limiter and drive it. I don't know what happened or what is between the limit command and tcu but it solve the problem as well. Also after a while u dont need to active limit and everything works well.
Another reason is the low voltage on battery because alternator can't charge battery well and solenoids confused to help for executing commands. I hope this helps you.
Sorry for my bad English

Do you mean this speed limited rod?
what speed did you setup?

Interesting suggestion about the speed limiter (I'm assuming cruise control for Americans?).

Regarding the battery, is that really relevant when the car is running? I would think that the alternator would provide an ample amount of voltage regardless of the battery health. Maybe I'm wrong on that.

Yes, it is.
Average like 100. Just active it.

Cruse / Limet = push it to orange led turns on.
On my opinion, the main reason for this problem, alternator is not supplying the required voltage to the transmission parts at low speed, because this problem has been reported in all cases at low speeds on sport mode 1to2 or comfort mode 2to3, and when the speed increases this problem is solved by supplying voltage through the alternator. The effects of voltage cannot be denied in any way, especially for transmission, which may cause several errors or failures due to power fluctuations, while all parts may be healthy. switch on the pre-ignition on the KM menu, and Press the reset button three times on the panel to display the voltage, usually cars with transmission problems are at 12.2 in ignition and idle mode and finally in acceleration until they reach electrical stability, which becomes 13.4 while it should be 14.2.

Thanks for being the 6th driver out of 7 to post how replacing TCC PWM solenoid fixed that annoying tranny jerk!

The 7th driver with positive results posted below.

I'm hoping to be #8, just dropped my car off to the dealership. Will post back with results soon, as folks had requested.

the dealership .... ouch

Hello. I recently took the car to a car service specialized in automatic transmissions, where, following the checks and the correlation of that jerk with the TCC lock-up moment, it was decided to recondition it and replace the TCC valve. The problem is that even after that the car does the same thing. I took it back and they said they would change the valve block. I don't know what to do anymore..

Hi all seniors,

i read thru the whole post and realize i have the same issue of jerking at low RPM. The trick of replacing the PWM solenoid as stated in this post, i would like to try get my workshop to replace that part and try. However i am quite new to merc and its parts seeking advise from all you guys here to see if you are able to direct me to the correct part. i dont know which position senor or what is that part called.

My car VIN : WDD2120472A371183
Engine : M - Engine:271860 30 176217271.

Thank you all, and especially OP, Amgen! My 2004 e55 transmission runs so smooth now! The jerkiness was starting to get really bad, and I really did not want to rebuild the whole transmission and torque converter, but thankfully found this thread. I did these fixes myself, and I am definitely not an experienced wrencher. I also took the valve body apart to put in a couple of upgrade kits from Sonnax and Transgo, parts below. I was able to do this without a lift, too. Getting the valve body back in place was tough, but I used my jack to help lift and hold it in place. I actually did this twice, because the first time I got it seated correctly and bolted in, I saw the plastic solenoid covers sitting on my workbench and after about 2 minutes of cursing pulled out the valve body again hehe.

I had some trouble getting the transmission fluild level right after finishing up. I completely overfilled it because I didn't realize you needed to be measuring the fluid level with the dipstick after the transmission warmed up so when I drove around, I was leaking transmission fluid all over. I guess there must be a relief or overflow vent where it was coming out. I then used a pump from harbor freight to suck some of the fluid out.

A couple of tips from the mistakes I made:
- When putting the valve body back in place under the transmission, make sure the plastic gear selector is seated on the gear shifting pin. It slides back and forth pretty easily from the valve body. Also, you can't put it back in after you put the valve body back together, it needs to be in there before you bolt the two halves together. You'll see the placement of the gear selector it in some of the youtube videos.
- If you are going to do the Sonnax TCC Damper Valve Sleeve Kit, you have to get the old damper valve out by using the new one and pulling out creating a suction. And there is a retainer ring that you clip on the damper sleeve after putting it all the way back into the valve body. The video by T.AA. shows exactly how at about 16 min in...

Parts:
- Mercedes Automatic Transmission Torque Converter Lockup Solenoid - Genuine Mercedes 2402701700
- TransGo 722.6-A SHIFT KIT® Valve Body Repair Kit fits
- Sonnax Overlap Control Valve Sleeve Kit 722.6 Mercedes Benz 68942-05K
- Sonnax 68942-23K TCC Damper Valve Sleeve Kit 722.6 Mercedes (the transgo kit already comes with these, but the Sonnax ones have O-rings on them so I didn't use the ones in the Transgo kit)
- FCP Euro tranmission service kit

Here are the videos I used, they were a big help too:

Hello Majorkook!

I´m so glad your gearboxissues are solved now!

That little solenoid has driven many 722.6 gearboxowners almost mad...

Best wishes,
amgen.