Mercedes transmission 722.6 electronic connector leak

Repairing leak from automatic transmission 722.6
Leaking from electronic connector.
Replacement part # A2035400253, Pilot Bushing. $22.
Enjoy.

[Gripen]

Thanks for the great video!
The 7mm screw in the pilot bushing needs to be tightened down to 2.5nm, hope that helps anyone watching this.

[johnswanger]

Just a heads up to anyone who finds this video. First, to be clear, this guy's video's are great. However one thing I would have at least mentioned is the electric conductor plate. For this repair in the video, I'm sure the TCM harness connector replacement worked just fine, especially if you are just wanting to get running again. Shorts in this connector from fluid in the housing can cause all sorts of shifting problems, including "Limp mode" ( won't shift/stuck in second only, high rpm, etc"
If you are doing this repair, you may want to also consider doing the electronic conductor plate I mentioned above. It can be found online, usually including the "pilot bushing", for $120-$200, genuine Mercedes. As you have to drop the trans pan, drain, and pull the TCM wire and remove the connector, all that is left to do is remove the valve body, and there's the conductor plate. Replace it, and most likely you will never need to open your trans again except to do a fluid exchange many tens of thousands of miles latter.
The connector, the conductor plate, and the wiring connector in the gear shifter housing are the 3 most common causes of Limp Mode on the 722.6 NAG 1 transmission.

I know that's not the point of this video, but to those who may be looking for the source of leaking AND trans problems, might as well do the other repair.

[emmanuelgomez]

By far one of the best DIY videos I've ever seen. I have to change this similar plug on my 300c, which if not mistaken; also uses a 5 speed Mercedes transmission (trust me I'm no mechanic). Thank you so much for doing this, really made my day!!!

[jonrandall]

Mr Diesel Mercedes...your videos are extremely well done and helpful. I have a USA 1998 Benz C280 with the 722.6 The automatic trans is stuck in first or second gear. I am not sure if this is limp mode or not. But I cannot go over 30 mph without the tach running up to 4000 or 4500 rpm's. I removed the valve body and replaced the Conductor Plate with a German OE style version. I did not test any of the shift solenoids. I also replaced the Connector. I just purchased this car, and noticed trans. oil had managed to flow uphill on the wiring harness that runs from the connector and plug up into the passenger side foot well and coated the wires, and also put some fluid into the Transmission Control Module. I have some electronic cleaner, but did not spray it into the plug which pushes into the connector. I did spray cleaner into the plugs which plug into the TCM. I carefully opened the TCM and noted there is trans. fluid residue and small drops inside my TCM. I wiped it off. After all this, my car still won't shift out of first or second gear (whichever it is stuck in). I have tried to shift it manually, but it won't. My check engine light yields code P0715 (Input/Turbine Speed Sensor A Circuit) This speed sensor is part of the Conductor Plate I replaced above the valve body, I believe. I wonder if my TCM is contaminated, or the harness that plugs into the TCM is bad also due to trans. fluid? Someone told me I should be looking at the Gear Selector Switch or Shift Micro Switch, which is part of the Auto Trans. Shift Lever. In the USA, this part is normally called a Neutral Safety Switch. Drinks and liquids can easily fall into the shifter and short out this Shift micro switch on these cars. I wonder if you have suggestions on what direction I should try next ?? THANKS

[TheEpmedia]

Excellent documentation and video, sir. Thank you.

[chrisnanfeldt]

Caution: there are several pins on the conductor plate itself that must not be bent or the adapter and the wiring harness plug will break one off. Then you will need a new conductor plate. Take care to spray clean the crap out of the wiring plug "grooves" that the white plastic retaining ring rides in. If super clean from debris, it will plug in as smooth as butter, you may choose to slightly lube the o-rings and then you will not need to "push really hard" and possibly damage your pins on the TCP. Obviously make sure the transmission housing is super clean so the o-rings make the proper seal. Ive had to repeat these steps several times to fix my leak on a 2006 Jeep Grand Cherokee Laredo sport. 3.7L v-6.

[skateboardcraze]

thanks for the help,
Installing the part on my 2000 clk430 was very tricky, much less room than in the video.

[deans]

Great job on this video. I will use it to replace my connector. Thank You from Michigan, U.S.A.!

[douglasgower]

great video, well explained, clear viewing and easy to follow. many thanks.

[seshachary]

most educative. awesome video. The best one in this topic. Thank you Regards

[dieselmercedes]

you have to drain fluid, otherwise it will spill all over you … i did replace fluid and filter, because fluid was dirty …..thanks.

[sephirothAD]

This is the best tutorial I've seen yet, I'm going to attempt this on mine here in the coming few weeks.  Thanks!

[DewhirstEric]

Great video - thanks for taking the time to step through it carefully - I appreciate it!

[johnswimcat]

Great video. My box has stuck in 2nd so I'll get underneath and have a look at this tomorrow. 2008 Vito 115 Auto, 722.6 box

[thegarre]

Can you tell me bed time stories please? I love your voice.

[NBDY_SPCL]

This is a great video, however, there is another electronic connection on the back side of the transmission that NO ONE is talking about. What is it, and how does one fix that one if it is leaking?

[BeastVladden]

Great job making this video, useful, easy to see & understand.
Comment from John Swanger also makes appropriate informative addition...👍
Reminder to all first time DIYers
ALWAYS start from simple fixes like this 13 pin connector replacement first👆(them are also less expensive typically )

[clicksbyklauss]

GREAT TUTORIAL! I CHANGED MINE AND THEN CLEARED THE CODE WITH MY CHEAPER SCANNER AND IT WAS STILL IN LIMP MODE. TOOK IT TO MERCEDES AND THEY CHECKED THE CONNECTOR AND CLEANED IT BETTER THEN I DID I GUESS AND THEY DELETED THE CODE AND CAR RAN GREAT FOR THE DAY BUT NOW ITS BACK IN LIMP MODE WITH THE SAME CODE. I CHECKED THE CONNECTOR TO SEE IF MAYBE IT WAS LEAKING AGAIN BUT IT WASNT. ANY INFO ON WHAT MY NEXT STEP SHOULD BE?

[danedwards]

BEAUTIFUL !!! made this job very easy....thanks!!

[Aligator]

Best man 👍👍 you make very clear and informative videos.

Best wishes from germany 😉