Mercedes-Benz Transmission Conductor Plate Repair

Background

Unlike other Euro manufacturers, Mercedes-Benz designs and builds their own transmissions. And they are absolutely brilliant. With proper maintenance, they last well over 200K miles. One of the most popular ones is the 722.9, the first 7-speed automatic in a passenger car. It is widely used in the MB lineup, including:

• C-Class
• E-Class
• S-Class
• SLK
• GLK
• CLK

The 722.9 is a technologically advanced, powerful, and very fuel efficient transmission. As it is in such widespread use, its weak spots are well-known, and proven solutions have been developed to address them. Having worked in hundreds of them, we at CarHavn know them very well.

The Issue

The conductor plate, or VGS module, has manufacturing issues as shipped form the factory. The initial supplier for the module, Siemens VDO, seems to have had a rare slip. The module fails as early as 50K miles.

Symptoms

A failing VGS will cause a very noticeable impact on your transmission:

• Loud 'thump' noise as you shift into D or R
• A noticeable 'bump' as if you were hit in the rear bumper as you shift into D or R
• The car will go into limp mode, not going over 2K RPM
• A Check Engine Light on (sometimes)
• Diagnostic Trouble Codes set in the car's computer

Fault Codes will include 2767, 0717, and 0718.

Repair

This is a delicate repair that needs a highly-trained Mercedes mechanic, very specific original Mercedes parts, specialist tools, and a laptop with the DAS OEM software to perform final adjustments.

The transmission oil pan, filter, and valve body need to be removed to access the VGS module. Then the solenoids need to be carefully removed, and cleaned, and reinstalled along with the new VGS module. Then module programming and coding needs to take place - this can only be done with the original DAS software.

Parts List

This is the parts list we generally use (subject to change on a case-by-case basis):

• Mercedes Updated Conductor Plate, 000270260080
• Transmission Filter and Fluid kit for 722.9 transmission

Additional Work

This is a great time to replace the transmission fluid and filter, and service all the other gearboxes as well.

Result

A smooth shifting transmission! One the module is programmed and the codes cleared, the car will come out of limp mode, no more thumping noises, and you'll be back to the luxurious ride you are used to.