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Discussion Starter #1
2001 E320 wagon 4Matic 176,000 miles, 722.6 4-speed automatic
It drove normally to the end of the day. The next day, the engine still starts and sounds normal in all regards, but does not move forward or reverse.

The shift lever moves out of park with the brake pedal depressed and is indicated correctly on the instrument panel, showing P, R, N, D when selected.

I have used a Autel MaxiLink ML629 OBD2 Scanner, however it has failed to connect to the system on many attempts. The same scanner works perfectly on my Cadillac and Chevrolet.

I found ATF had migrated uphill to the Transmission Control module under the hood.
Replaced:
  • the conductor plate
  • all six solenoids in the valve body
  • Transmission Plug Wire Harness Connector Adapter
  • Transmission filter and fluid
  • Shift lever assembly
  • Transmission control module
I’m 40 miles from a dealer, so getting it in for a proper diagnosis is pretty tough.
I’d sure appreciate some input or fresh ideas, if anyone cares to share.
Many thanks.
 

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w163 02 ML500 W210 97 E50Amg w202 99 C230K w124 - need more space, time to build again
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Welcome up-on-two, :)

It seems like you have performed the necessary repairs.
With a transmission limp mode, after repairs, you still need to erase the error codes in the tranny module.
If you cannot read it with your present scanner, then you need one that can read the additional modules in the MB.
Not all scanners are created equal, just because it can read your other 2 vehicles, does not mean it will read your MB.

Does not mention MB.
 

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1999 E320, 2003 E320 Wagon, 2005 C230K SS, 2010 Accord LX w Eibach & Koni FSD's
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2,653 Posts
You need to read and erase transmission codes thru the 38 pin socket in the fuse box under the hood. This requires a scanner capable of reading MB transmission codes and a COMPATIBLE 38 pin adapter cord. Cheap eBay cords will NOT work! Been there, done that!

I use this one + a male DB15 x male DB15 cord for my Autel MD802:

 

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1998 E320 base sedan @ 160kmiles
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I have used a Autel MaxiLink ML629 OBD2 Scanner, however it has failed to connect to the system on many attempts. The same scanner works perfectly on my Cadillac and Chevrolet.
If you connected the scanner to the OBD2 port, you should be able to read the ECU (engine computer) fault codes, if any and the ECU live data, like the rpm, engine load, etc.....
If you are not able to access the ECU, I suggest you check the fuse that provides power to the diagnostic ports. This is a 7.5 amp fuse under the hood at the passenger side module box, on K40 relay and fuse module. It is the only 7.5 amp fuse so you can't miss it.

If this fuse is blown, no scanner will work.

Do you have the check engine light ON ? Normally P0700 / P0715 codes pop up (current / pending) when you have this condition. This "usually" points to rpm sensor issues.
 

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Discussion Starter #5
You need to read and erase transmission codes thru the 38 pin socket in the fuse box under the hood. This requires a scanner capable of reading MB transmission codes and a COMPATIBLE 38 pin adapter cord. Cheap eBay cords will NOT work! Been there, done that!

I use this one + a male DB15 x male DB15 cord for my Autel MD802:

Excellent! I've placed an order for that cable. We'll see what it provides. Many thanks.
 

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Discussion Starter #6
If you connected the scanner to the OBD2 port, you should be able to read the ECU (engine computer) fault codes, if any and the ECU live data, like the rpm, engine load, etc.....
If you are not able to access the ECU, I suggest you check the fuse that provides power to the diagnostic ports. This is a 7.5 amp fuse under the hood at the passenger side module box, on K40 relay and fuse module. It is the only 7.5 amp fuse so you can't miss it.

If this fuse is blown, no scanner will work.

Do you have the check engine light ON ? Normally P0700 / P0715 codes pop up (current / pending) when you have this condition. This "usually" points to rpm sensor issues.
I'll check on that fuse, thanks.
The ck engine light is not on, but the message "3 MALFUNCTIONS" does appear after running the engine.
 

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1999 E320, 2003 E320 Wagon, 2005 C230K SS, 2010 Accord LX w Eibach & Koni FSD's
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Did you adjust final transmission level with car running, in park and up to temperature (trans) with the proper measuring tool?
 

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Discussion Starter #8
Did you adjust final transmission level with car running, in park and up to temperature (trans) with the proper measuring tool?
A good question. there seems to be some ongoing discussion about the proper ATF level for the 722.6 trans. Why did MB choose to not include an actual dipstick in this application? Seems like an error in judgment to me.

I did not want to run it long enough to get it up to temp, because of possible internal mechanical damage that may result if something was wrong inside the trans. So after installing the new filter, gasket and original pan, I ran the engine a few minutes to get the ATF fully circulated into the trans passages and used a proper dipstick to measure it cold.
 

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1999 E320, 2003 E320 Wagon, 2005 C230K SS, 2010 Accord LX w Eibach & Koni FSD's
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A good question. there seems to be some ongoing discussion about the proper ATF level for the 722.6 trans. Why did MB choose to not include an actual dipstick in this application? Seems like an error in judgment to me.

I did not want to run it long enough to get it up to temp, because of possible internal mechanical damage that may result if something was wrong inside the trans. So after installing the new filter, gasket and original pan, I ran the engine a few minutes to get the ATF fully circulated into the trans passages and used a proper dipstick to measure it cold.
You should be good then. I just thought you might not have enough fluid in the trans if the correct measuring tool wasn't used.
 

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Discussion Starter #10
Excellent! I've placed an order for that cable. We'll see what it provides. Many thanks.
Still waiting on the delivery of that connecting cable
Six weeks to delivery! They must be ROWING to the US.
Maybe the Chinese virus is slowing the rowers.
still waiting ....
 
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