Took a photo. Does it look like the AT Pan gasket may be faulty ? AT Fluid change may be in order. What do you think ? Where is the sensor that everyone talks about from where it leaks ?

 

One more question

After twisting the ivory colored collar and removing the plug...How do I get the housing out of the tranny case?

 

Hey, ladboy.

Since this issue is not on point for the other thread I made a new one for you, plus this will get it some exposure it would have otherwise missed.

That's certainly a significant leak, probably is the connector but the guys who have suffered through that will chime in to confirm or "disconfirm", as it were. (Bonus points if you recognize the movie line.)

Take care and enjoy the ride,
Greg

 

yeah it looks like the pan gasket needs to be replace.

 

it would be smart for all w210 owners, especially the ones with the earlier years to check the connector that greg is talking about. the part costs like $10 and is super easy to change. when i checked my car it was a little wet, it wasn't bad where the atf went to the tcm, but i'm really glad i caught it early.

 

Connector Location

Where is the connector that everyone is talking about ? I would appreciate if someone can post a photo of the location. Thanks.

 

Where is the connector that everyone is talking about ? I would appreciate if someone can post a photo of the location. Thanks.

Here is the 13 pin connector and location.

 

if i remember it right is connected to the left wire (passenger side) from the above pic, and you don't need to take the pan off. follow the wire to the pan and i think a little rectangular piece clips off, and take it out. it was a while back so i could be a little off, and also mine is a 1997, and could be a little different from the newer ones since it was the first 722.6 version.

 

A few pictures

I have quickly put together some of the pictures I took when replacing mine last summer. Please do not take it as a tutorial but rather as a simple illustrative guide. This is a relatively simple job.

If no access to a lift, raise the front on ramps. First step is to remove the side stainless steel shield shown hanging on some the pictures. The electric plug is a two part component. The ivory color piece is a twist off mechanism, rotate it probably 3/4 of a turn or so and remove the electric plug, which will stay hanging from its wire harness. Installation is the reverse.

The red O ring needs to be purchased separately. The last picture shows the piece you have to purchase that does come with its O rings.

I apologize for any omissions and hope it helps.

Cheers

 

The red O ring needs to be purchased separately. The last picture shows the piece you have to purchase that does come with its O rings.



Cheers

franasia, very nice write up. so you replaced the red o-ring also along with the last piece? when i replaced mine i didn't change the red o-ring, only the connector part that twists off (the last picture from franasia's pdf). next time i change the tranny fluid i will for sure.
was your connector wet with atf? in my case when i twisted the connector off, the part that doesn;t twist off was a little wet (picture 1 from franasia;s pdf). i cleaned it with some electronics cleaner and let it dry/drip for a little bit until i was sure it was dry, then i twisted on the new connector part (last picture from franasia's pdf) and put everything together. and i didn't lose a lot of atf, so didn't need to add more.
by the way the pic shows the location of the connector from the above pic, even though franasia's pictures make it pretty clear where it is.

 

I have quickly put together some of the pictures I took when replacing mine last summer. Please do not take it as a tutorial but rather as a simple illustrative guide. This is a relatively simple job.
...
I apologize for any omissions and hope it helps.

Cheers

Hey, Franasia.

Thank you for taking the time to put this together, quickly or not. Do you still happen to have the part numbers from your invoice, etc? If so please PM them or post and I'll add them in. I think this is really useful, and a great example of the forum working for everyone.

Denials, disclaimers and apologies aside, I thought this was worthy of inclusion in the DIY thread, and exercising my mini-mod prerogative, it is.

Take care and enjoy the ride,
Greg

 

Part No. 203 540 02 53. Cost $7.70.

 

Hello,
Forgive me , but I am lost here . May I know what does the connector do for the tranny, and what is it called? Does it monitor the system? . . . . . Sorry for the idiotness , thanks.

 

It hooks up the EGS (a.k.a. TCM or TCU), Transmission Control Module, to the transmission. On some earlier units the EGS gets flooded with ATF. Mine, which is the newer version, is a completely sealed unit. I attached some pictures I took when replacing the electric plug. The lower picture shows the EGS location in the engine compartment with it removed.

Hope it helps.

Cheers

 

AT Plug Adapter

Franasia/tirona - Thanks for putting the great pictorial & for point it out in my photo. It looks bigger than I thought. I found out that the 'device' is called AT Plug Adapter - (part number - J2050-277685 at mercedesshop dot com). Costs just $7.18. Planning to DIY this and here is the list that I think I need.
1. AT Cover Pin (plastic part that is one time use)
2. AT Drain Plug Seal (Washer)
3. AT Filter
4. AT Pan Gasket
5. AT Plug Adapter (device that we are talking about)
6. AT Drain Plug
7. AT Fluid (MB)

Does the 2001 model come with a magnet ? Am I missing anything here ? I will take photos when I do this.

 

Thanks for the input. Sorry for the delay in response. Sure helps in my next DIY.

 

I had mine replaced 2 years ago with same issue. It was very nice of you to show picture so others could benefit from your experience.

 

Very important question!

I missed on that indeed!

It is held by a bolt centered in the connector housing. This is after pulling out the actual electric plug. If I recall well, its a 7mm head. The bolt is attached to the housing so there's no risk of dropping it. In other words, the new part comes with the bolt and makes it very easy to figure out once you've bought the new part.

Cheers

 

Great help on this topic

My 1998 E320 4matic wagon 182000 miles began acting up (flare in 3rd to 4th gear upshift- into neutral. Check Engine Electronics light and CEL on. Code P0700). Had the transmission fluid and filter changed but still has some "flares" on that 3rd to 4th upshift. Car went into "neutral" and I had to use the manual gearshift gate to drop down and get tranny to catch into 3rd gear-- but I still had all the gears-- I was not locked into "limp home" mode.

PS I have the 722.664 tranmission in this model. Been great for 10 years but we did not have prior ATF and filter changes b/c no dealer service writer or indie mechanic was recommending it to us.

I found and followed this thread and checked my EGS, "transmission control module" in engine compartment and it was soaked- maybe 4 ounces of ATF drained out. I opened it and cleaned it with electronics cleaner and with computer type compressed air spray and let it dry completely. Then I went to the electric plug at the tranmission end of the wiring harness and it too was leaking and covered in ATF.

So off the MB dealer for the $13 plug (same part numbers as previously noted). And no, they did not have the red O ring for me to buy. Service tech said maybe EGS and harness are compromised by ATF contamination and very expensive to replace them so he suggested "clean it up and sell the car." Well I am probably giving the car to a relative and I do not want to give a problem to him.

The electric plug was not a simple installation but that is b/c the space is a little tight, even on ramps. Follow the pictures and instructions- remove the shrouds and brakets. The parts you are looking for are right where the passenger side O2 sensor wiring goes in. I cleaned the male plug and the socket of ATF (as other ATF contamination) as best I could at the tranny end with electronics cleaner spray and paper towels. I had some trouble getting the 7mm bolt in the new socket to "grab" but I needed to drive the new plug socket in deeper and solidly (wood block and soft taps with a rubber mallet) once it was properly aligned (be vewry sure it is aligned before tapping it or you will damage the pins that protrude through the bottom of the new socket)-- that compressed the new O rings a little and seated the new plug socket --- then the 7mm bolt grabbed and it pulled the new socket in tight. (I needed a flexible 1/4 inch drive and 7 mm socket and then a small extension on a 1/4 inch drive to get in there to the bolt head. There is a metal line in the way of using a simple 1/4 screwdriver handle on mine).

There still could be some compromise in the electronic connector plate that is inside the tranny (that is just behind that new plug socket we are installing) -no way to know that just yet. But it looks like this has stopped the ATF leak on that electric plug.

Then with all assembled, I drove her "hard" in Drive. It ran through all the gear upshifts smoothly with no skipping or flare. So fingers crossed and I will have all the Mercedes codes cleared (OBDII won't do that) and we will see what we see.

Many of these 722.6 issues on early models like mine are "electronic" communication issues and are not hardware issues in the transmission at all. There was no metal or debris in my pan on ATF fluid and filter change - but my filter was broken off and it was just sitting in the pan! These issues and connections are not always checked out thoroughly by many technicians (dealers and indies) who just replace and replace, often at a much greater expense.

So for some hassle, my labor, and a $13 part (less online if you can wait), I may have dodged a $5000 repair for buying and installnig a remanufactured 722.664 transmission in this car. Not what I wanted to do at 182000 miles really.

So long live the forum, I say. It would not have been possible to do this without the posts in this thread. Even if you don't DIY, you will have more information to address the issue with your dealer or indie mechanic.

Thanks, fellows.

 

Hi,

I have recently got the ATF fluid, filter and gasket changed in the dealer, but they didn’t change the connector only the seal.
Do you reckon I should change the connector, and if yes can I do it without having to drain the ATF.

Thanks, Maldit

 

For a ten dollar part that has been superceded at least twice, I can't understand why they didn't replace the whole thing. Probably at this point I'd just keep an eye on it. If it starts to leak again, get it fixed. The Mercedes dealer repair has a one year warranty, so you have time. If you DIY, you can do it without draining the fluid. Just have a container nearby to catch a couple of cups of fluid that will drain out. Either that or work real fast.

Len

 

Hi Len,

The car was sent to the dealer as the auto box wasn’t working properly.
It had a problem with the valves, but it never leaked.
Decided to get the plug changed while they were fixing it, but when I asked them to also change the plug they said no need that with the new seal on the plug it Wold be OK.
I just don’t trust them, will it be OK or should I change the plug?

Thanks, Marcos

 

Well, the connector had to come out to change the two O rings. The new part comes with the O rings. Still don't understand why they didn't change it. It's very unusual for a dealer not to try to replace entire units. I would assume then that while they had the part in hand, they determined that the part was still dry or at least still servicable. At this point, I'd probably still just watch it and hope that if it does leak, it does so within a year so that the repair is on their nickel.

Len

 

So I'm laying under my car unscrewing the B1 P2 O2 sensor and what do I see? A small puddle of fluid and wetness on the right front corner of the AT pan. Gee, I wonder what it could be. Local stealer marks up it's parts ($14+ with tax, they work hard at keeping their name) but at least I caught it in time.

Thanks again, Franasia.

Take care and enjoy the ride,
Greg

 

ATF Fluid Changed

After almost 6 months of ordering parts that I finally got a chance to change the ATF fluid. Ran into couple of issues :

1. Bought ramps because I did not want to get under the car with just jack-stands but the front bumper touched the ramps. Used a hydraulic jack to lift up the car on one side at a time and inserted the ramps under the front tires.

2. My torx bit broke (stuck inside) while opening the drain plug. Finally ended up with dropping the pan with the fluid in it - was a messy job trying to catch all the fluid in large aluminium food trays .

3. Changing the filter and putting the pan back was a breeze - the bit is still stuck in the drain plug. I guess I won't have to worry about it for another 60-70k miles.

4. Changing the plug which had leakage was the toughest job. After removing the old plug I put the new one and inserted the socket. The electrical socket got stuck half way when I pushed the tab upwards so that the socket pushes in. I think the tab slipped the notches and it got stuck. Took me a lot of prying and pulling to get it off. Noticed that the notches in the new plug had slipped and were also damaged. I cleaned up the old plug with gasoline, put the new 'O' rings and fit it up. Its been a week now - see no leakage.

5. I put a little over 5.75 liters of MB ATF fluid. Will have to check the level one of these days. Running is the same as before - i did not notice much difference. The leak is gone.

But for this wonderful forum I would not be able to afford an E320. I absolutely love this car inspite of all its issues. Next project is fixing the clunks in the front suspension - specially during the rains. Thanks for all your help and support - God Bless !

 

After almost 6 months of ordering parts that I finally got a chance to change the ATF fluid. Ran into couple of issues :

1. Bought ramps because I did not want to get under the car with just jack-stands but the front bumper touched the ramps. Used a hydraulic jack to lift up the car on one side at a time and inserted the ramps under the front tires.

2. My torx bit broke (stuck inside) while opening the drain plug. Finally ended up with dropping the pan with the fluid in it - was a messy job trying to catch all the fluid in large aluminium food trays .

3. Changing the filter and putting the pan back was a breeze - the bit is still stuck in the drain plug. I guess I won't have to worry about it for another 60-70k miles.

4. Changing the plug which had leakage was the toughest job. After removing the old plug I put the new one and inserted the socket. The electrical socket got stuck half way when I pushed the tab upwards so that the socket pushes in. I think the tab slipped the notches and it got stuck. Took me a lot of prying and pulling to get it off. Noticed that the notches in the new plug had slipped and were also damaged. I cleaned up the old plug with gasoline, put the new 'O' rings and fit it up. Its been a week now - see no leakage.

5. I put a little over 5.75 liters of MB ATF fluid. Will have to check the level one of these days. Running is the same as before - i did not notice much difference. The leak is gone.

But for this wonderful forum I would not be able to afford an E320. I absolutely love this car inspite of all its issues. Next project is fixing the clunks in the front suspension - specially during the rains. Thanks for all your help and support - God Bless !

Question for you... did the new o-rings give you trouble when trying to put the plug back in? I just bought a new plug (only needed the o-rings but they're not sold separately.) and the rings are stopping the new plug from going in. Is that possibly because the new rings are harder and therefore need some pushing or...? I don't know, which is why I'm curious as to whether you had trouble getting the new adapter plug into the tran or not? Thanks!

 

This forum rocks!

Just finished replacing this AT plug/connector in my 1998 E430. Had a small leak in this area, ordered the part, read this sticky and I'm done.

Some notes to add to this sticky -

1) Canadians - I bought the parts from Auto Parts Online Canada. They were great. Ordered the parts yesterday at 5:00 PM, they arrived today at 3 PM. Can't beat that.

2) To get at this plug, you first have to remove the harness and heat shield as Franasia mentioned. This harness also supports the O2 sensor wires. It is fitted to the transmission pan and held in place by two bolts, which can be removed with a T30 Torx bit. The passenger side bolt also holds the small metal heat shield in place which shields the connector. Once both bolts are removed, both the harness and heat shield will come off.

3) To remove the connector, first loosen the white plastic collar by turning it counterclockwise. The male plug should now pull straight out easily. Note the orientation, though the plug has been designed to fit only one way.

4) To remove the connector, the part that is being replaced, first loosen the bolt inside it with a 7mm socket, as mentioned. With my car model/year I had no problem using a regular 1/4" ratchet, there was plenty of room. Once the bolt is fully loosened, the connector should pull straight off.

5) Installation is the reverse. Make sure the plug is aligned correctly. Put it in place with a bit of light pressure and rotate until you feel it click in. Then push in firmly until you can turn the 7mm bolt inside and it grabs. Then tighten it with the ratchet and put everything back together.

Took about 45 mins, start to finish - and a huge thanks to all who posted the pictures and advice here, it was invaluable.

 

Also, unless you have drained the fluid to service the transmission, have a container ready to collect about two liters of ATF that will flow out the connector hole once you remove it. Be sure to check the fluid level hot after you've done the job.

Len

 

I had the front of the car jacked up pretty high (2' maybe?) and hence only a dribble came out, maybe a cupful. Still an excellent idea to check level afterwards.

 

I noticed a little seepage from the right front corner of the pan just like Greg did. Wish I would have caught it when I did filter and fluid recently. Bought the wire harness adapter today at the local parts house. I forgot about the red O-ring. Is it necessary to change the red O-ring? It must be a dealer item, right?

 

Guys,
Do you know O-Ring part number? I cannot find it in EPC.

 

I believe you have to purchase the whole Plug/Adaptor now. It is only about $6.50 on most on-line sites, There is a red O-ring on the plug itself that does not need to be replaced. When I pulled the electrical plug on mine there was some fluid on it which surprised me cuz it was barely leaking on the outside. I cleaned it with some contact cleaner and put it back together. I was surprised that the car shifts up and down much smoother now.

 

thank you, dnewman!
I already bought a Plug/Connector and going to replace it on next Friday. I'm asking about new O-ring - just in case if this one will be in bad shape... Or maybe does it make sense just replace it?

 

I am not sure what O-ring you are refering to. The adapter comes with 2 new O-rings on it. The plug that you pull out of the adapter has a red O-ring on it that does not need to be replaced. I believe all it does is keep dirt ect. from getting into the plug area. I think I read somwhere if you want to replace the Red oring you have to replace the whole plug which would be a big job. Hope this helps you.

 

Yes, I'm referring to connector's red O-ring.

 

I was told by the parts man (who in this case seemed to have a good deal of knowlege on the subject) that the red O-ring does not need to be replaced and is available only if you order the harness.

I've had no leaks since I replaced the connector, leaving the red O-ring in place.

Take care and enjoy the ride,
Greg

 

Thanks a lot for your help!