In this article and video we will be replacing the electrics (conductor) plate on the 7G transmission. See how to remove it for rebuild or replacement. See parts 3 – 4 for the remainder of the procedure
Reviewing the replacement part, you can see that only the ECU and connector will be replaced.
Begin by removing the T40 Torx solenoid fasteners and hold down brackets.
Then remove each solenoid from the valve body. When removing, be sure to place them in the order they were removed, as mixing up a solenoid location when reinstalling can cause shift issues. We prefer to lay them in the order they were removed to keep them organized.
Once the solenoids are removed, carefully inspect for Swarf or debris on the solenoid screens. The solenoid shown has debris on the screen and will need to be cleaned.
To remove any debris from the solenoid screen, use a small container of new transmission fluid and swirl solenoid around in the fluid. The debris will fall out of screen. Use only transmission fluid to clean. Do not use brake cleaner, detergents or brushes to clean as damage can occur.
Working at the valve body, remove the seven T30 Torx ECU electrics Plate fasteners.
Note range switch position when removing.
Note transfer tube position when removing.
Lift ECU electrics plate straight off valve body.
Wipe down valve body using a lint free cloth. If needed, use new transmission fluid as a cleaner.
Install the new ECU electrics plate at an angle then lay flat on the valve body.
Install fasteners finger tight.
Then torque to 8Nm in a crisscross pattern.
Install the solenoid in the same location they were removed from.
Install and torque the solenoid hold down brackets to 8 Nm.
Remove the Valve Body sealing O-rings and replace with new. When installing the new O-rings, coat them with new transmission fluid.
Install the transfer tube into the transmission. The seal lip should face up.
Before installing the valve body, note the part number for later use. It may be needed during programming.
Next the valve body is installed. Check the position of the shift selector pin and align it with the shift selector in the valve body when installing.
The pin should slide into the slot of the selector when installing.
Push and hold valve body flush against transmission to fully seat the main ECU electrics connector. Then, install the new fasteners finger tight.
Torque the valve body fasteners initially to 4Nm.
Once torqued, tighten valve body fasteners an additional 90°.
Snap the fill tube onto the transmission pan.
Then, install the transmission pan gasket.
Install the new transmission filter by pressing it straight up into the transmission.
Hold the transmission pan in place, install the fasteners finger tight.
Then torque the transmission pan fasteners in a crisscross pattern to 4Nm.
Once torqued, tighten fasteners an additional 180°.
Working at the left side of the transmission, reconnect the intelligent shift module (ISM) electrical connector by pressing it straight on, then sliding the lock up.
Reassemble the oxygen sensor electrical harness mounting bracket and reconnect the oxygen sensor electrical connectors.
That’s the end of step 2. In Step 3 we will begin the coding and programming procedure.
SCAN makes complex functions simple. Check our other videos and articles for more helpful tips and procedures for Mercedes-Benz vehicles. iSCAN sf: https://www.iscantech.com/iscan-sf/
Need help with a diagnostic issue. contact iSCAN Support On Demand SOD: https://www.iscantech.com/sod/