@Steal_th Don't make things complicated. Buy and Openport passthru cable and install Xentry passthru. Once installed, run a quick test and that should give you a picture of what is going on. If the ONLY module that has no comms is the transmission, then most likely you will need a new one.

 

A new transmission or TCM (i.e., conductor plate and valve block)?

 

Just the conductor plate (transmission control module). No need to replace transmission or valve body.

 

plus Xentry SCN coding to pair security
@BenzNinja (a recognized MBworld *SPONSOR*) can help you with that and much more.

 

How come no news/update from OP ?

 

Hi! I have been away for over a week and hope to get to the car this weekend.

 

Hi, everyone!
Apologies for the radio silence and thanks for all the help! It was the dead TCM, unfortunately...
Is there any statistics on which TCM is better or more durable : Siemens or Continental?

 

Is oem the latter?

 

It's the "same difference"....

early mega mergers

Conti owns Siemens 👏

 

I actually did not know that, good to know. So both of the TCM is built identically?

 

I don't think you have a choice.

 

It may be quite late for this info, but incase a future reader comes along curious...
If memory serves, Siemens makes the VGS1 & 2 Conductor plates, while Continental makes VGS3. I also understand there are compatibility issues between valve bodies originally paired with VGS1 (& also 2?) conductor plates. There were cases of new conductor plates being needed, only Conti VGS3 units available, said units were NOT compatible/could not be successfully programmed & coded to the cars in need & the only remedy was the purchase of a new conductor plate AND valve body as an assembly.

I'm going through a mild Hell w/ TCM issues which is looking to be a GND fault w/ the TCM's chassis ground, however my electrical connector is also leaking & still cannot confirm/deny that a new conductor is the only remedy to sort this on a 722.9. Don't you wish you had a 722.6 instead?

I know I do. Or better yet, a 718? (The 6 spd manual).

 

Do you have photo of the oil leak ? Or you are seeing oil at the wire harness connector into the TCM ?
I know 5 speed has issue with the oil ingress from TCM connector into harness side connector and I replaced my friend's 5 speed TCM connector as preventive.
I have not yet heard 7 speed has the same issue, but would love to prevent it.

thanks

 

Hello, Mr. Prihadi,
https://mbworld.org/forums/mercedes-...nightmare.html

This is the story so far. I do also have pictures. My checking the electrical connector was simply done on a whim, but I was greeted with an outpouring of ATF on my shirt & the floor. At this point, I'm unsure if the fluid has wicked itself into the front SAM.

I've cleaned the GND for the TCM (front left wheel well), found no voltage drop anywhere, have power at fuse 33 & relay R is working. Still, I'm unsure TCM can ever get proper voltage when its connector is wet & if conductor plate (or conductor plate PLUS valve body) is the only solution, this car may have to go.

As of now, I've found maybe 4 documented cases of 722.9's leaking from the electrical connector. One slkworld forum post & benzworld (w211) post, both of which unresolved. One youtube short, unresolved and poster did not seem to understand the difference between 722.6 & 722.9 (which is scary because apparently his shop is working on that car!) I did see mention from forum member @konigstiger somewhere mention that the external o rings found at the bottom of the conductor plate plug can sort this issue, yet I've also been told said o-rings are only for external leaks (which makes more sense given their orientation.

 

ATF came pouring out! There is also of course a seal here. Likely not sold separately as far as I know

Aforementioned o-rings located here. Also likely not sold separately?

A wk after initial finding of leak & cleaning. Cleaning bought me about 2-3 days of CEL free driving. This was also before GND cleaning....Going to check for 3rd time now & take voltage readings

I would share those forum posts I mentioned, but I didn't save them & not sure I can find them quickly. I was reading so much, my head was spinning trying to find this secret ancient hidden mystery that is the 722.9 doing what we thought only the 722.6 does, yet without the simple solution of the 722.6. But again, nothing came from those forum posts unfortunately. It may take some time, but I will post the findings of my solution, even if it is selling the car. If I'm going through conductor plate, valve body, programming & SCN coding, it's going to be on something with 8 cylinders & no grandma tan interior!

 

Dang, this is a scarry prospect....

Here is a leaking oil at the connector too.


The external o-rings has nothing to do with connector's leaking oil internally. External o-rings leaking oil will be directly oil flowing out of the seal interface alu body side of tranny.

------

2 images below is from here : https://mbworld.org/forums/e-class-w...tor-p0748.html



.


-------


This oil leak scenario at connector's internal I think would be like how the sealing/casting of camshaft position sensor plastic material failed internally and allows oil to leak to
connector pins and wick its way to the wiring harness side and eventually engine's computer.



Basically praying it wont happen so soon to one's 722.9 is the only possible way.


---------

This kind of leak between oil and composite material reminds me of when boat builder made fuel tank using fiberglass, and insert metal fittings ( hose barb ) at fuel tank bottom for fuel hose during the process.
The metal fitting is basically fiberglassed to the tank fiberglass material.
In 10+ years, the fuel will seep eventually at the fitting OD, as metal to fiberglass bond is actually not a 100% foolproof long term.

In fact in swimming pool the same thing happens. The PCV water inlet pipe is casted into the pool concrete, some caulking is added here and there, but basically the PCV pipe
bonding to concrete is not a 100% waterproof joint. So pool will experience water leaking out of it, absorbed by the concrete which concrete is actually quite porous.
This happens to many pools but owners do not know it, more so when pool is build away from home and surrounded by garden/earth.
The water loss is blamed to sun evaporation, but when properly tested, we know there is a leak at the PCV pipe interface to concrete.

 

So upon inspection of the connector the other day, I was shocked to find a completely clean & dry connector on both male & female ends!



Roughly 3-4 wks after initial finding of leak

Hard to get a clear pic of, but confirmed clean/dry with mirror

Regardless of this nice find, I do still have low voltage instability remaining and a possibility of conductor plate failure, or at the very least, selection range sensor failure. Both I still doubt given the fact that once these errors are triggered, the car continues to drive flawlessly.

That was the same video I was referring to about the connector leak. Possibly the only one?

This is certainly confusing to me. I suppose if you run into this yourself, just clean the connectors twice, & then on 3rd inspection it will no longer leak! Hahaha

Great comparisons with the marine fuel tank & pool gradual leaks. The more time passes, I feel like many systems on this car are not long-term solutions! As I continue to troubleshoot, I can't shake the feeling the right tool for the job might be a W124, W201, or an R129

 

Dont give up....
Low voltage stored code should have freeze frame data, does your scanner have that data ?

 

Thank you.
I believe so, it's the iCarsoft MB V2. The only time I tried to use it for freeze frame (about a yr ago), it crashed. Thanks for the reminder. I'll add this to the list for tomorrow.