722.9 G7 solenoids interchangeability W211

[Kurda]

Hello, I need help please
EPC shows 2 types of solenoids blue and black caps and 2 different part numbers for all 8. Are the blues changeable with each other and the blacks with blacks?

After experiencing intremnint and brief limp mod around 3rd and 4th gear without any fault codes in the dashboard or scanner. I decided to remove and check the gearbox valve body because 1 in10 limp mod and scans I would get 2 fault codes "2802 -001 Transmission control ETC no signal" and " 0741 actuation of torque converter lockup clutch is not possible" please see the attached pictures.


While bench-checking the conductor plate I saw overheating marks on the converter solenoid (another picture), removed and cleaned all 8 solenoids cleaned outside of the valve body and conductor plate, put everything back together and refiled ATF and drove the car for around 8 miles changing gears and gear mods fine, but the intremnint limp mod was the same, then I heard a grinding sound from the rear a couple of times and went . And when reversed to park the car I tried to drive forward the car wouldn't move but in reverse.


So now the gearbox is slipping in Drive (or stuck in 4th+ gears ) but not in Reverse
I have changed the converter solenoid with a new blue Cap solenoid but still car only moves in Reverse.
have I misplaced a solenoid, or caused the release of dirt buildups to travel and block some ATF passage by cleaning on the bench.
How do I check the positions of solenoids and can MB Star scanner do this (actuate solenoids while only the wiring harness is attached)

 

[Jobsworth]

Your problem lies with the B2 brake. The B2 is engaged for gears 1,2,3 and 4. For 5th gear the B2 is unlocked and clutch K1 engages. Reverse does not use the B2, so that is unaffected. The grinding you mention is worrying. That suggests to me that you might have a mechanical issue in the B2 rather than an electronic one.

 

[Jobsworth]

Power flow chart. Apologies for crappy picture from my breakfast table

 

[Kurda]

Thank you Jobsworth for your advise,
That was the first time I heard the grinding sound for about 3 seconds both times within 15 seconds and went away before I came to park the car and found out the car doesn't move forward.

If I have not misplaced the solenoids the only 2 thing I think of I have done wrong is caused the release of debris buildups to move and block ATF passage somewhere, or somehow contaminated the ATF during refile (did use 3 litters none MB brand ATF ).

I will be taking out the conductor plate again and taking it apart, clean it, drain converter, and flush the ATF coling radiator using MB brand fluid.

But I need to rule out the misplacing of solenoids first.

 

[Jobsworth]

The colours and placing in your picture above are correct, providing that the one we can’t see is black.

 

[Jobsworth]

Fyi, the solenoid that controls the B2 brake is the blue one on the other end of the line that has the torque coverter lock up solenoid on it. (Which is also blue)

 

[Kurda]

Yes you are correct it is a black cap solenoid.
You mean the top right corner one in the photo the colour deteriorated to green and the shape of the cap has deformed a bit

Can replace it with a new blue cap? Is there anything needs to be done in MB star

 

[Jobsworth]

In your picture top right is the tcc solenoid. Top left is the B2 brake. Both are blue ones. Your tcc solenoid is the one that appears greenish blue

 

[Jobsworth]

I think its very worth your while to pull all the solenoids again and check the O rings on the bottom. They can split if you catch them pushing back in. That will lead to low pressures and burned out friction discs very easily

 

[Jobsworth]

 

[Kurda]

I will do, again thank you very much will update soon

 

[Kurda]

Hello again, latest update and bad news still the car only engages in Reverse but not moving in Drive and turns fresh fluid to black.

Yesterday I drained the atf, removed the fluid pan and was greeted with chunk of metal about a finger nail size black finish and half rusty, and drained the torque converter via the drain plug (span the crank shaft pulley to find it using a wrench). The fluid was very dark brown or close to black as old engine oil, keeping in mind I did a complete atf flush about 6 weeks ago and the car has done less then a 1000 miles since.
Then removed the conductor plate and toke it apart to check for any fluid pass blockage or broken springs and pistons, all looked fine so cleaned (using brake cleaner) and put everything back together. And with a friend of mine whom is good with electric stuff tested the solenoids all stopping at 4 continuity or resistance as he called it (forgive here) and actuated them hearing a click for all the solenoids using a 9v alarm battery.

Put the solenoids back on, mounted the conductor plate back, pumped 3 litters of atf started the engine in P selecting R N D for 5+ seconds while pumping another 4 litters. The car was level and oil temperature around 50C, pumped 1 more litter, started the car, went through the gears turned the car off, removed the drain plug almost 1 litter drained until started to dripping, put the drain plug back on. But the car still only moves in reverse.

I decided to remove the conductor plate again and swap the solenoids around to see anything changes. Did this still the car only moves in reverse, but the fresh 3+ fluid from the pan has turned to very dark brown again.

Jobsworth as you mentioned the issue lays at some mechanical parts as, considering the earlier grinding sound, the chunk of metal in the pan, and turning fresh fluid dark. is it a gearbox replacement next? any advise please.

 

[Jobsworth]

Any large parts in the pan can only be bad news. Fyi, the fluid level is checked with the car running in neutral and the trans fluid temp at 45 degrees. If you have set the level with the engine switched off it has too little fluid in it. Regardless, it sounds like its a full teardown now.

 

[Kurda]

Thank you and sorry for the long replies.
Shouldn't the fluid level effect reverse too, mb star mentions checking fluid level too and going to developer mode and do something in german language (see photo).

Yes you are right Wise and the dealer counter say 9 to 10 litters of fluid to do a flush but I could only manage to put 7 litters in, is it because D is not engaging to soak up another 2 litters at least.

Iam lost now
Is it my converter
Do I get a complete box and converter
Do I have to program it to the car

 

[Kurda]

I managed to get the car moving forward! By revving above 2000 rpm and once the car moved I went around the block switched to Manual mode the gear wouldn't downshift any lower than 4th gear on kikdowns and kept in 5th and 4th gear no matter how fast or slow I drove.
I think it is a faulty conductor plate I will call the ECU rebuild company that my inde uses.
Any ideas.

 

[Jobsworth]

Have you topped the fluid up?

you MUST set the level with the ENGINE RUNNING

 

[Kurda]

I haven't yet should I do that tomorrow before doing anything else

 

[Jobsworth]

I would

 

[Kurda]

I have set the level again as you recommend engine running going through the gears and back to park then neutral while the engine running and the temperature at 45, but no joy and I still get the slipping tourq convertor high friction power fault.