Caution! Do not start the engine with the oil pan removed or without transmission oil, and do not tow the vehicle. Follow the instructions for the DSG - 0D9 automatic transmission. Rules for maintaining cleanliness when working on the gearbox, especially with the mechatronics or transmission oil pump open, contamination can lead to gearbox failure. The mechatronics is identified by the letter designation of the gearbox. Take into account the topic "contaminated oil", as well as the instructions for replacing the oil filter. When changing the transmission oil, it is not always necessary to replace the transmission oil filter. Therefore, it is necessary to follow the instructions for when to replace the transmission oil filter and when not to. When disconnecting and connecting the battery ground wire, additional work must be performed. If the mechatronics is replaced with the gearbox removed, it is necessary to install the gearbox on a mounting stand.
Set the control lever to the VRN position. Disconnect the battery ground wire with the ignition off. Remove the lower noise-insulating engine cover. Remove the front left wheel arch cover. Drain the coolant. Lift the locking bracket "arrow" and remove the left lower coolant hose from the radiator.
Remove protective cover "A" from the bottom of the gearbox "see arrows" if present. Unscrew nuts "2" securing holder "1" to the oil pan and remove the holder from the stud on the oil pan.
Note: The stud is welded to the front of the gearbox to the oil pan.
Move the pipes and wires in the oil pan area upwards and tie them up. Install a pan to collect the oil under the gearbox. Unscrew the threaded plug to check the level "see arrow".
Note: Behind this plug there is a plastic bypass tube, which is tightened with an 8 mm Allen key to a torque of 3 Nm. The length of the bypass tube determines the oil level in the gearbox; when replacing this tube, observe the part number.
Remove the bypass tube. Approx. 5.0 l of oil will leak out. Leave the oil collection pan under the gearbox. Screw on the bypass tube and tighten to the specified torque.
Remove the stabilizer bar strut by unscrewing screws -1, 2- and 3-. Then you can push the gearbox a little "back" to the bracket of the mounted units, this will allow you to get enough space to remove the mechatronics.
Unscrew the screws "see arrows" and remove the transmission oil pump cover "A". Touch it with your hand (without gloves) to the ground to remove the electrostatic charge.
Caution! The mechatronics for the dual clutch gearbox "J743" may only be handled or touched after the electrostatic charge has been discharged via a grounded object, such as the main contact to ground. Never touch the plug-in contacts in the gearbox connector with your hands, so that static discharge does not damage the ECU and mechatronics.
Unlock connector "1" of the mechatronics by turning it to the left and disconnect the connector from the gearbox.
Loosen the screws "see arrows" of the oil sump attachment "A" and turn them out in a cross order.
Note: There is still transmission oil in the oil pan, as it cannot drain away without leaving any residue.
Remove the oil pan with the oil pan seal. Replace the oil pan gasket. It is necessary to replace the gearbox oil pump cover and oil pan screws.
Caution! If you do not remove the transmission oil pump cover, when removing the mechatronics for the gearbox with a dual-disc clutch "J743", you can damage the bracket of the speed sensors at the gearbox output "G195" and G1S6-on the back side.
Unlock the lock "1" in the "direction of the arrow" using the unlocking tool "T10465" and carefully remove it.
Release the wire from the retaining tabs "see arrows", first at the top, then at the bottom.
Note: Do not pull the connector by the wire! If the wire is damaged, the primary shaft torque sensor "C182" / clutch temperature sensor "G509" must be replaced.
Loosen the mounting screws "1" through "10" in the given sequence and unscrew.
Remove the mechatronics unit from the gearbox housing until the bracket for the output shaft torque sensors "G195" and "G196" "B" on the rear side comes out of the gearbox housing. Carefully tilt the mechatronics unit for dual clutch gearbox "J743" downwards.
Remove the mechatronics unit for the dual clutch transmission "J743".
Caution! Never lift the mechatronics unit by the bracket of the speed sensors at the gearbox output "G195" and "G196" or place it on it.
Transport and store the mechatronics as shown in the figure.
When handling the mechatronics, pay special attention to the long torque bracket of the output shaft "G195" and "0196" "see arrow" (if the "bracket" is damaged, the mechatronics must be replaced).
