DSG Transmission

Self-Study Program

Course Number 851403

The 02E Direct Shift Gearbox

Design and Function

Volkswagen of America, Inc.Service TrainingPrinted in U.S.A.Printed 05/2004Course Number 851403

©2004 Volkswagen of America, Inc.

All rights reserved. All information containedin this manual is based on the latestinformation available at the time of printingand is subject to the copyright and otherintellectual property rights of Volkswagen ofAmerica, Inc., its affiliated companies and itslicensors. All rights are reserved to makechanges at any time without notice. No partof this document may be reproduced, storedin a retrieval system, or transmitted in anyform or by any means, electronic, mechanical,photocopying, recording or otherwise, normay these materials be modified or repostedto other sites without the prior expressedwritten permission of the publisher.

All requests for permission to copy andredistribute information should be referred toVolkswagen of America, Inc.

Always check Technical Bulletins and theVolkswagen Worldwide Repair InformationSystem for information that may supersedeany information included in this booklet.

Trademarks: All brand names and productnames used in this manual are trade names,service marks, trademarks, or registeredtrademarks; and are the property of theirrespective owners.

i

Table of Contents

The Self-Study Program provides you with informationregarding designs and functions.

The Self-Study Program is not a Repair Manual.

For maintenance and repair work, always refer to thecurrent technical literature.

Important/Note!

New!

Introduction ................................................................................... 1

Selector Lever ................................................................................ 3

Direct Shift Gearbox Design......................................................... 9

Basic Concept, Torque Input, Multi-disc Clutches, Driveshafts, OutputShafts, Reverse Gear Shaft, Differential Gear, Selector Lever Park PositionInterlock, Synchronization, Torque Transfer in the Vehicle, Power Flow inthe Transmission

Mechatronics Module .................................................................26

Electro-hydraulic Control Unit ...................................................28

Transmission Lubrication System.............................................. 30

System Overview ........................................................................ 38

Sensors ........................................................................................40

Actuators ..................................................................................... 48

Functional Diagram..................................................................... 54

CAN-Databus-Links ..................................................................... 56

Diagnostic .................................................................................... 57

Service .......................................................................................... 59

1

Introduction

The current transmission market in Europe is primarily manual transmissions. However, themarkets in Japan and the United States use primarily automatic transmissions. Both of thesetransmissions have benefits and drawbacks.

Manual transmission benefits:

• High efficiency

• Strength

• Driver control

Automatic transmission benefits:

• High comfort

• Ease of use

Based on this information, Volkswagen set out to design a transmission that combined thebest characteristics of each of these transmissions. The result is the Direct Shift Gearbox(DSG).

Transmission Fluid Filter Transmission Fluid Cooler

Transmission Fluid Pump

Mechatronics

Multi-disc Clutch

S308_014

The dual wet-clutch design and automatic shifting programs of this transmission will satisfythe automatic transmission driver’s demands of high comfort and ease of use.

The fast and smooth shifting capabilities, which can be controlled by the driver, satisfy themanual transmission driver’s demands.

Also, this transmission offers fuel consumption characteristics as low as most vehicles withmanual transmissions.

2

The Direct Shift Gearbox has the following features:

• Six forward gears and one reverse gear

• Normal driving program, “D”

• Sport shifting program, “S”

• Selector lever and steering wheel Tiptronic switches (optional)

• Mechatronics integrates electronic and electro-hydraulic controls into a single unit, locatedinside of the transmission

• Hillholder function: if a vehicle is brought to a stop by light braking, the clutchpressure rises and the vehicle remains motionless

• Creep regulation: permits “creeping” of the vehicle when the brake pedal is released andthe accelerator pedal is not depressed

• Emergency running mode: when in emergency running mode, the vehicle can only bedriven in either 1st and 3rd gears, or only in 2nd gear

Transmission Fluid Filter

Transmission Fluid Cooler

Electric Connection withthe Vehicle

S308_003

Introduction

Part number DSG 02E (Direct Shift Gearbox

Torque Maximal 258 lbs-ft (350 Nm) (engine dependent)

Clutch Two wet multi-disc clutches

Gear ranges Six forward gears, one reverse gear (all synchronized)

Operating mode Automatic and Tiptronic mode

Fluid volume 1.9 gallons (7.2 liters Direct Shift Gearbox fluid G052 182

Weight About 207 lbs (94 kg) in front drive vehicles, 229 lbs (104 kg)in 4Motion vehicles

3

Selector Lever

OperationThe selector lever operation is the same asin other automatic transmission vehicles.However, the Direct Shift Gearbox alsooffers the possibility of being shifted withTiptronic. This can be activated eitherthrough the selector lever or by using theoptional steering wheel buttons.

The selector lever controls the selectorlever interlock and the ignition key interlockof the vehicles equipped with an automatictransmission. The interlock functionoperates the same as before, but theconstruction is different.

The selector lever positions are:

P - Park

To shift the selector lever out of thisposition, the ignition must be ON and thebrake pedal must be depressed. In addition,the unlocking button must be depressed onthe selector lever.

R - Reverse

To shift into Reverse, the unlocking buttonmust be depressed.

N - Neutral

In this position, the transmission is idling.

If the selector lever remains in Neutral foran extended period of time, the brake pedalmust once again be depressed to changethe lever position.

D - Drive

This position allows for automatic shifting offorward gears.

Unlocking Button

Steering Wheel Switches

S308_004

S308_063

S - Sport

This position allows for automatic shifting offorward gears but will hold each of thesegears until a higher RPM before shifting.

+ and –

The Tiptronic functions can be controlled inthe right cover plate of the selector leverand can also be controlled with the steeringwheel switches.

4

Selector Lever Design

The selector lever includes the followingcomponents:

Selector Lever Sensor System ControlModule J587

The Hall sensors in the selector lever inputunit record the position of the selector leverand communicate this position to theMechatronics via the CAN-Bus.

Shift Lock Solenoid N110

This solenoid locks the selector lever in the“P” and “N” positions. The solenoid iscontrolled by the Selector Lever SensorSystem Control Module J587.

F319

N110

Hall Sensors to identify the Selector Lever position

Selector Lever Sensor SystemControl Module J587

Locking Pin Hole for “N”

Locking Pin Hole for “P”

S308_098

Selector Lever Park Position InterlockSwitch F319

If the selector lever is in the “P” position,the switch sends the signal “Selector leverin “P” position” to the Steering ColumnElectronics System Control Module J527.The control module requires this signal tocontrol the ignition key interlock.

Selector Lever

5

Selector Lever

The Shift Lock Solenoid N110 functions asfollows:

Selector lever locked in “P”:

When the selector lever is in “P”, the springactivated locking pin is in the locking pinhole “P”. As a result, it prevents theaccidental shifting of the selector lever.

Selector lever unlocked:

Once the ignition has been switched on andthe brake pedal has been applied, theSelector Lever Sensor System ControlModule J587 energizes the Shift LockSolenoid N110. As a result, the locking pin ispulled out of the locking pin hole “P”.

The selector lever can then be moved inother positions.

Selector lever locked in “N”:

If the selector lever remains in the Nposition for more than 2 seconds, J587 willenergize N110, allowing the locking pin toengage in the N locking pin hole. Thisprevents accidental shifting of the selectorlever into a drive gear. This pin will beunlocked when the brake pedal isdepressed.


S308_101

S308_102

Locking PinHole for “N”


CompressionSpring

Locking PinHole for “P” Locking Pin S308_103

6

Emergency release

In case of a power supply failure to theShift Lock Solenoid N110, the selector levercan no longer be shifted because the shiftlock “P” remains activated by springtension.

Apply mechanical pressure on the lockingpin with a small object to disengage theshift lock. This releases the selector leverinto the “N” position.

S308_104

Selector Lever

7

+F319

J527

-

Selector Lever

Ignition key interlock

The ignition key interlock prevents theremoval of the ignition key from the ignitionassembly if the selector lever is notengaged and locked in the Park position.

It operates electromechanically and iscontrolled by the Steering ColumnElectronics System Control Module J527.

The interlock functions as follows:

Selector lever in “P”; ignition switched OFF.

If the selector lever is in “P”, the SelectorLever Park Position Interlock Switch F319 isopen.

The Steering Column Electronics SystemControl Module J527 recognizes that theswitch is open. The Ignition Switch KeyLock Solenoid N376 is not energized.

The compression spring in the solenoidpresses the locking pin into the disengagedposition.

Magnet N376

S308_093

Retaining Lug

Ignition OFF

Locking Pin

Compression Spring

S308_092a

8

- +F319

J527

The interlock functions as follows:

Selector lever in “D”, the ignition isswitched ON.

When the selector lever is in “D”, theSelector Lever Park Position InterlockSwitch F319 is closed.

The Steering Column Electronics SystemControl Module J527 energizes the IgnitionSwitch Key Lock Solenoid N376. The lockingpin is pushed through the solenoids,against the strength of the compressionspring, and into the lock position.

In the lock position, the locking pin preventsthe ignition key from being turned back andremoved.

Only when the selector lever is pushed in“P” will the Selector Lever Park PositionInterlock Switch F319 open while thecontrol module deactivates the solenoid.

The locking pin is then pulled back by thecompression spring. The ignition key can berotated and pulled out.

“Ignition On”

N376S308_091a

Selector Lever

9

Direct Shift Gearbox Design

Basic Concept

The Direct Shift Gearbox is basically amanual transmission designed to operatelike an automatic transmission. In place ofa dry clutch, two wet clutches are used.

These wet clutches rotate in transmissionfluid. The Mechatronics Control ModuleJ743 controls clutch operation and gearselection.

Basically, the transmission is alwaysengaged.

Outer Disc-Carrier K2 Outer Disc-Carrier K1 Dual-mass Flywheel

Input Hub

Clutch Driving Disc

Main Hub

S308_007c

10


Direct Shift Gearbox Schematic diagram

Input Shafts

Output Shaft 2

Reverse GearShaft

Drive Gear ofthe Differential

S308_089b

Output Shaft 1

Multi-disc Clutches

Input fromEngine

11

Torque Input

The torque is transferred from thecrankshaft to the dual-mass flywheel. Thesplines of the dual-mass flywheel on theentry hub of the dual clutch transfer thetorque to the driving disc of the multi-discclutch.

The dual-mass flywheel transfers thetorque to the input hub via splines.

Therefore, the following components turnat the same speed as the dual-massflywheel and input hub:

• Clutch driving disc

• Main hub

• Outer disc-carrier K1

• Outer disc carrier K2

Outer Disc-Carrier K2 Outer Disc-Carrier K1 Dual-mass Flywheel

Input Hub

Clutch Driving Disc

Main Hub

S308_007a


12


Multi-disc Clutches

The torque is transferred into the respectiveclutch through the outer disc-carrier. Byclosing the clutch, the torque is transferredto the inner disc-carrier and then to thecorresponding input shaft. There is alwaysone multi-disc clutch activated in all drivegears.

Multi-disc clutch K1

Clutch K1 is the outer clutch and transfersthe torque to Input Shaft 1 for 1st, 3rd, and5th gears and Reverse.

Increasing the transmission fluid pressurein the clutch K1 fluid pressure cavity willclose the clutch. As a result, piston 1moves and presses the multi-discs of clutchK1 together. The torque is transferred toInput Shaft 1 by the multi-disc clutch.

When the clutch opens, the spring washerpushes piston 1 back into its initial position.

Inner Disc-Carrier K1

Outer Disc-Carrier K1Piston 1

TransmissionFluid PressureCavity K1

Input Shaft 1

Spring Washer

Clutch K1

S308_039

13

Multi-disc clutch K2

Clutch K2 is the inner clutch and transfersthe torque to Input Shaft 2 for 2nd, 4th, and6th gears.

Increasing the transmission fluid pressurein the clutch K2 fluid pressure cavity willclose the clutch. The piston K2 closes thepower flow to Input Shaft 2 through themulti-disc clutch.

When the clutch opens, the coil springspush piston 2 back into its initial position.

Clutch K2

Piston 2

Fluid Pressure Cavity K2 Inner Disc-Carrier K2

Coil Spring

Input Shaft 2

S308_040


14

Drive Shafts

The engine torque is transferred to theinput shafts by the multi-disc clutches K1and K2.

Input Shaft 2

Input Shaft 2 is a hollow shaft andis coupled to the multi-disc K2 byexternal splines.

The helical gear wheels for 6th, 4th and 2nd

gears are on Input Shaft 2. A commongearwheel is used for 6th and 4th gears.

The Driveshaft 2 Speed Sensor G502 islocated next to the second gear wheel.This sensor measures the speed of InputShaft 2.

Input Shaft 1

Input Shaft 2

S308_010

Impulsion Wheel

6th/4th Gears 2nd Gear

S308_084


The Input Shafts may be referred to asDriveshafts in the repair information.

15

Input Shaft 1

Input Shaft 1 rotates inside of Input Shaft 2,which is hollow. It is connected to themulti-disc clutch K1 by external splines.

The helical gear wheel for 5th gear, thecommon gear wheel for 1st gear andReverse, and the gear wheel for 3rd gear arelocated in Input Shaft 1.

The Driveshaft 1 Speed Sensor G501 islocated between 1st, Reverse and 3rd gearwheels. This sensor measures the speedof Input Shaft 1.

A strong magnet can destroy theimpulsion wheels!

Impulsion Wheel

5th Gear 1st Gear/Reverse

3rd Gear

S308_085


16


Output Shafts

Just as there are two input shafts, there aretwo output shafts in the Direct ShiftGearbox.

Stretched representation

1st Gear 3rd Gear 4th Gear 2nd GearOutput GearWheel

Sliding Collar

Mounting position in the transmission

Drive Shafts

S308_086 S308_105a

The following are located on the OutputShaft 1:

• The triple synchronized control wheelsfor 1st, 2nd and 3rd gears

• The single synchronized control wheelfor 4th gear

• The output gear wheel for engaging thedifferential gear

The output shaft meshes in the gear wheelof the differential gear final drive.

The overall length of the transmission wasshortened by using a common gear wheelon the input shafts for 1st gear and Reverse,as well as a common gear wheel for 4th and6th gears .

Output Shaft 1

17

Output Shaft 2

Stretched representation Mounting position in the transmission

Impulsion Wheelfor G195 andG196

5th Gear 6th Gear Reverse Output GearWheel

S308_87 S308_105b

The following are located on the OutputShaft 2:

• An impulsion wheel for thetransmission output RPM

• The control wheels for 5th and 6th gearsas well as the gear wheel of the reversegear

• The output gear wheel for engaging thedifferential gear

Both output shafts provide the torque tothe differential gear through their outputgear wheel.


18


Reverse Gear Shaft

The Reverse Gear Shaft changes thedirection of rotation of Output Shaft 2 and,as a result, changes also the direction ofrotation of the gears for the final drive ofthe differential gear. It is meshed with the1st gear and Reverse common gear wheelon Input Shaft 1, and with the Reversecontrol wheel on Output Shaft 2.


Gear Wheel for 1st Gearand Reverse

Reverse Gear Shaft

S308_105cS308_088

19

Differential Gear

Both output shafts transfer the torque tothe differential drive gear.

The differential gear transfers the torquethrough the drive train to the wheels.

The park position lock wheel is integratedinto the differential gear.


Drive Gear of theDifferential

Parking Lock Wheel

S308_089

S308_105d


20


Parking Lock

A parking lock is built into the differentialgear assembly to help ensure a completestop of the vehicle and prevent the vehiclefrom unintentionally rolling away when thehand brake is not activated.

The parking lock is mechanically controlledby a connecting cable between the selectorlever and the parking position lock lever inthe transmission.

The only function of the connecting cable isto operate the parking lock.

Parking Lock

Parking Lock Wheel

S308_023

Function

The parking lock is engaged by shifting theselector lever in the “P” position. As aresult, the parking lock engages into theteeth of the parking lock wheel.

A detent spring locks the lever in place andsets the parking lock in its position.

If the parking lock does not lock into a gapbetween the teeth of the parking lockwheel, the spring will be compressed. Ifthe vehicle moves, the parking lock will lockinto the next gap of the parking lock wheel.

The park position lock is disengaged byshifting the selector lever out of the “P”position. The slider is pushed back to theright into its initial position and thecompression spring 2 pushes the parkinglock out of the gap of the parking lockwheel.

Lever

Connecting Cable to the Selector Lever

Slider

CompressionSpring 1

Detent Spring

CompressionSpring 2

Parking LockWheel

Parking Lock

S308_079a

21

Synchronization

To change gears without interference ornoise, the Direct Shift Gearbox usessynchronization on each gear.

The purpose of a synchronizer is to bring tothe same speed the gears to be meshedand the selector sleeve. This allows foreasy shifting.

The synchronizer rings are made of brassthat is coated in molybdenum. Themolybdenum allows for long life.

Gears 1, 2 and 3 are equipped with triplesynchronization. This triple synchronizationprovides a larger heat transfer surface. Thelarger heat surface is needed because therotation speed differences are higher in thelower gears.

Gears 4,5 and 6 have simple conesynchronization. Since the speeddifferences are not as high, the largersurface area of the triple synchronizers isnot needed.

Intermediate Ring Inner Ring

Outer Ring Friction ConeFriction ConeSynchronization

RingS308_022 S308_078


The reverse gear has a double-conesynchronization.

The simple synchronization is made of:

• The synchronizing ring

• The friction cone of the shifting gearwheel

The triple synchronization is made of:

• An outer ring (synchronization ring)

• An intermediate ring

• An inner ring (2nd synchronization ring)

• The friction cone of the shifting gearwheel

Triple Synchroniser Simple Synchroniser

22


Torque Distribution

The engine torque is transferred from thedual-mass flywheel to the transmission.

For front-wheel drive vehicles, this torque istransferred to a drive shaft on either side,which allows the wheels to turn.

For all-wheel drive vehicles, there are driveshafts for the front wheels and a drive shaftgoing to the rear differential to drive therear wheels.

Direct Shift Gearbox

Differential Gear

Haldex Coupling

Rear DifferentialS308_020 S308_021

Vehicles equipped with the Direct ShiftGearbox have a Haldex coupling todistribute the torque to the rear wheels.When the Haldex coupling locks, torque ispassed from the input shaft to the reardifferential and out through the rear inputshafts to the rear wheels.

23

Transmission Power Flow

The engine torque is transferred to thetransmission either through clutch K1 or K2.Each of these clutches drives a separateshaft.

• Input Shaft 1 is driven by the K1 clutch

• Input Shaft 2 is driven by the K2 clutch

There are two additional shafts needed totransfer the power to the differential:

• Output shaft 1 for gears 1, 2, 3, and 4

• Output shaft 2 for gears 5, 6 and Reverse

1st GearK1 ClutchInput Shaft 1Output Shaft 1Differential

S308_055_1


24


2nd GearK2 ClutchInput Shaft 2Output Shaft 1Differential

3rd GearK1 ClutchInput Shaft 1Output Shaft 1Differential

4th GearK2 ClutchInput Shaft 2Output Shaft 1Differential

S308_055_2

S308_055_3

S308_055_4

25



ReverseK1 ClutchInput Shaft 1Reverse Gear ShaftOutput Shaft 2Differential

S308_055_6

S308_055_R

The change of rotation direction for Reverse isperformed through the reverse gear shaft.


S308_055_5

26

Mechatronics Module

Mechatronics

The Mechatronics assembly is locatedinside of the transmission and immersed intransmission fluid. This assembly is madeup of both the transmission control moduleand electro-hydraulic controls.

The Mechatronics is the central controlmodule of the transmission. All sensorsignals from the transmission and otherrelevant areas of the vehicle are sent to theMechatronics assembly. As a result, theMechatronics assembly can monitor theoperation of the transmission and regulateoutput correctly.

Electro-hydraulic Control Unit

S308_095

S308_097

Central Connectorto the Vehicle.

Twelve sensors are located within theMechatronics assembly. These sensorsregulate eight hydraulic gear actuators, sixpressure modulation valves, five controlvalves and the pressure and cooling of bothclutches.

The Mechatronics assembly can adapt tolearn the positions of the clutches, thepositions of the gear actuators for eachspecific gear and the main transmissionfluid pressure.

27

The benefits of this assembly are:

• Integrated sensors

• Actuators located directly on theMechatronics assembly

• All interaction with the rest of thevehicle is done through a singleconnector

These features reduce the number ofconnectors and wires, providing betterelectrical reliability and lower weight.

However, this also means that thetransmission control module electronics areexposed to higher thermal and mechanicalloads. The Mechatronics assembly hasbeen engineered to easily withstand theseconditions.

ElectronicControl Module

S308_096

Mechatronics Module

28



The electro hydraulic control unit isintegrated to the Mechatronics module.

All the solenoid valves, pressure controlvalves, the hydraulic slider and the multiplexerare located inside the control unit.

N88 – Solenoid Valve 1 (Gear actuating valve)




N92 – Solenoid Valve 5 (Multiplexer valve)

N215 – Pressure Control Valve 1 (Clutch valve K1)

N216 – Pressure Control Valve 2 (Clutch valve K2)

A pressure relief valve is located outside ofthe hydraulic module. This valve prevents highinternal pressures that can damage thehydraulic valves.

N217 – Pressure Control Valve 3 (Main pressurevalve)

N218 – Pressure Control Valve 4 (Coolant valve)

N233 – Pressure Control Valve 5 (Safety valve 1)

N371 – Pressure control valve 6 (Safety valve 2)

A – Pressure Relief Valve

B – Printed Circuit Board

S308_033

N215

N218

N371 B N88 N233

N217

A

N92

N216

29

Valves have different shifting characteristicsaccording to their function. The twofunction types are:

•“Yes/No” control valves

• Modulation valves

The “Yes/No” control valve type includes:

• The gear selector valves and

• The multiplexer valve

The Modulation valve type includes:

• The main pressure valve

• The cooling fluid valve

• The clutch valves

• The safety valve

The gear actuator valves N89, N90 and N91can be seen by removing the printed circuitboard.

N89N92

N90

N91

S308_034


30

Transmission Lubrication System

Transmission Fluid System

The DSG transmission has a fluid capacityof 7.2 liters. This fluid must meet thefollowing requirements:

• Ensure clutch regulation and hydrauliccontrol

• Have a stable viscosity through theentire temperature range

• Withstand and lubricate the dual-clutch,wheels, shafts, bearings andsynchronizer rings under highmechanical loads

• No foam

• Allow for smooth operation of all valves

• Allow for correct operation of the dual-clutch and gear control piston

A separate transmission fluid coolerprevents the transmission fluid temperaturefrom rising above 135°C(275°F). This cooler uses engine coolant toreduce temperature.

.

Gear Actuator

Transmission Fluid Cooler

Transmission Fluid Filter

Transmission Fluid SprayingTube for Cooling the GearWheels

Valve Body

Transmission Fluid Pump Transmission Fluid Sump

S308_019

31

Transmission Fluid Pump

A crescent shaped pump draws thetransmission fluid and produces the mainpressure required for the hydraulic parts tooperate. It produces up to 26.4 gal/min (100l/min) and a maximum pressure of 20 bar(290 psi).

The transmission fluid pump supplies fluidfor:

• The multi-disc clutches

• The clutch cooling

• The gear shift hydraulic pressure

• The gear wheel lubrication

The transmission fluid pump is driven bythe pump shaft rotating at engine RPM.This pump shaft is a third shaft locatedinside Input Shaft 1, which rotates withinInput Shaft 2.

Crescent

PressureSide

Suction Side Return Pipe to Suction Side

S308_018

Pump Shaft

Dual-MassFlywheel

TransmissionFluid Pump

Input Shaft 1 Input Shaft 2 S308_036


32


Schematic Diagram

TransmissionFluid Pump

TransmissionFluid Cooler

Suction Filter

TransmissionFluid Filter

Transmission FluidSpraying Tube

TransmissionFluid Sump

Pressure Relief Valve Main Pressure Slide Valve

Pressure Control Valve 3

Oil Pump Return Pipe

Clutch Cooling Fluid Slide Valve

Cooling Fluid toward the Clutches

Lubrication/Cooling of Gear Wheels

To Multi-Disc Clutch K2

To Multi-DiscClutch K1

Gear ActuatorColor Coding

Regulated pressure, work pressure

Uncontrolled pressure

Controlled pressure, clutch cooling

Transmission fluid sump return circuit

S308_017a

33

Transmission Lubrication SystemDescription

The transmission pump draws thetransmission fluid from the sump, throughthe filter, pressurizes it and sends it to themain pressure slider valve.

The Main Pressure Valve N217 controls themain pressure slider valve. This regulatesfluid pressure inside of the transmission.

A transmission fluid channel from the mainpressure slider valve directs extra fluid backto the transmission pump suction side.

Pressurized fluid from the main pressureslider valve branches off into two channels.One channel directs the fluid to thetransmission fluid cooler, cooling the fluidand returning it to the sump. The otherchannel directs the fluid to the clutchcooling fluid slide valve.

Other features of the fluid circuit:

• The transmission fluid cooler is in theengine cooling circuit and uses enginecoolant to control temperature

• The transmission fluid filter is locatedoutside of the transmission housing

• The pressure relief valve limits the fluidpressure to 32 bar (464 psi)

• The individual gears are lubricated byfluid spray from directional nozzles


34


Schematic Diagram of Hydraulic Elements in the Transmission LubricationSystem

Pressure Relief Valve UVMain Pressure Slide Valve

Main Pressure Valve N217

Safety Valves N233 and N371

Pressure Accumulator

Check Valve

PressureSensor G194

ClutchValve N216

Multiplexvalve N92

Multiplex

PressureAccumulator

PressureSensor G193

Check Valve

Clutch ValveN215

Gear Actuator

To K2

To K1

N88 N89 N90 N91

S308_017b

Color Coding

Regulated pressure, work pressure

Uncontrolled pressure

Transmission fluid sump return circuit

35

Electro-hydraulic Control of theTransmission Fluid System.

Pressure Control Valve 3 for AutomaticTransmission N217

The Pressure Control Valve 3 for AutomaticTransmission N217 controls the mainpressure valve. This controls the mainpressure for all of the transmissioncomponents including:

• Pressure Control Valve 1 N215

• Pressure Control Valve 2 N216

• Clutch K1

• Clutch K2

• Solenoid Valve 1 N88




In addition to controlling the main supplypressure, N217 also controls:

• The transmission fluid return throughthe transmission fluid cooler,transmission fluid filter and spray nozzle

• Transmission fluid pump return circuit

Multiplexer valve

Solenoid Valve 5, N92, operates themultiplexer in the transmission. Themultiplexer is a slide valve that allows foursolenoid valves to have the control of eightsolenoid valves.

The multiplexer has two positions, homeand work. The default position is the homeposition and it is held in that position by aspring when N92 is not energized. In thisposition, gears 1,3,6 and Reverse can beselected.

When N92 is energized, pressure is appliedto the multiplexer and the spring iscompressed. In the work position, gears2,4,5, and Neutral can be selected. Also, inthe work position, the multiplexer spring iscompressed.

Safety valve

A safety valve for clutches K1 (N233) andK2 (N371) allows a quicker opening of therespective clutch. This is necessary whenthe actual clutch pressure is above therated pressure.

Pressure sensors G193 and G194

Pressure sensors G193 and G194 controlthe clutch pressure of clutches K1 and K2.

A pressure relief valve prevents an increaseof the main pressure that could result froma defective main pressure slide valve.


36


Clutch Cooling LubricationSystem

The mechanical friction in the multi-discclutches increases the temperature ofthe dual clutch.

To cool down the clutches, thetransmission fluid circulation systemincludes a separate clutch coolingsystem.

The coolant slide valve and thePressure Control Valve 4 N218 (clutchcooling valve) belong to the clutchcooling system.

The multi-plate clutches oil temperaturesensor G509 measures the fluidtemperature directly at the multi-discclutches’ fluid discharge.

Depending on the measured temperature,the pressure control valve either increasesor reduces the fluid pressure to the clutchcooling fluid slide valve. The clutch coolantslide valve opens or closes the fluidpressure for the fluid channel to the multi-disc clutches.

The maximum cooling fluid flow is 20 litersper minute. The maximum cooling fluidpressure is 2 bar (29 psi).

Clutch CoolantSlide Valve

Pressure Accumulator

MechatronicsTransmission FluidTemperature Sensor forthe Multi-Disc Clutches

S308_061

N218

37

Shifting Gears

Gear shifting is based on manualtransmission gearshift forks. Each forkshifts 2 gears.

The operation of the gearshift forks isperformed hydraulically in the Direct ShiftGearbox, instead of with a cam mechanismlike the one used in common manualtransmissions.

The gearshift forks are set in cylinder ballbearings, for smooth operation.

To shift a gear, the Mechatronics fluid issent to the left cylinder. Since the rightcylinder pressure is open, the gearshift forkmoves and activates the selector sleeve. Asa result, the gear is engaged.

Once the gear is engaged, the gearshiftfork pressure is switched off. The gear isstopped by a detent in the shift toothsystem and by the indexing socket of thegearshift fork.

When the gearshift fork is not activated, itis held in the neutral position by a detent inthe transmission housing.

On each gearshift fork, there is apermanent magnet. With this magnet, theposition sensor in the Mechatronics canidentify the exact position of the individualgearshift forks.

Fluid Pressurefrom the Mechatronics Indexing Sleeve

Piston

Cylinder

Position Sensor Magnet

Gearshift Fork

Sliding Collar

S308_047

S308_048


38

System Overview

Multi-Plate Clutch Oil TemperatureSensor G509

Sensor for Transmission RPMG182

Senders for Transmission OutputRPM G195 and G196

Driveshaft 1 Speed Sensor G501and Driveshaft 2 Speed SensorG502

Sender 1 G193 and Sender 2G194 for Hydraulic Pressure,Automatic Transmission

Transmission Fluid TemperatureSensor G93

Temperature Sensor (in ControlModule) G510

Gear Position Distance Sensors 1to 4, G487, G488, G489, G490

Tiptronic Buttons (on the SteeringWheel) E438 and E439

Sensors Direct Shift Gearbox (DSG)Mechatronics J743

39

Selector Lever SensorSystem Control ModuleJ587

CAN

Actuators


Pressure Control Valves

N215, N216, N217

Solenoid Valves

N88, N89, N90, N91,

N92, N218, N233, N371

Diagnostic Connector

S308_024

System Overview

40

Sensors

Sensor for Transmission RPM G182

The sensor for transmission RPM ispositioned inside the transmission housing.

It electronically senses the outside of thedouble coupling and records the inputtransmission RPM.

The transmssion input RPM is identical tothe engine RPM.

G182 is a Hall sensor that is integrated withthe Multi-plate Clutch Oil TemperatureSensor G509. Electrical wires connect bothsensors to the Mechatronics.

Signal utilization

The transmission input RPM signal is usedto calculate the multi-disc clutches slip. Forthis calculation, the control module alsouses the signals from sensors G501 andG502. With the calculated slip rate, thecontrol module can regulate correctly theopening and closing of the clutches.

G182S308_056

Effect of signal failure

In case of signal failure, the control moduleuses the engine RPM from the CAN as areplacement signal.

41

Driveshaft 1 Speed Sensor G501and Driveshaft 2 Speed SensorG502

The two sensors located in theMechatronics unit are Hall effect sensors.

Sensor G501 records the RPM of InputShaft 1.

Sensor G502 records the RPM of InputShaft 2.

To identify the shaft RPM, each sensordetects an impulsion wheel installed on therespective shaft. The impulsion wheel ismade of sheet metal. A coat of rubber-metal is deposited on the sheet metal. Thiscoat constitutes a ring of small magnetswith North and South poles. There is an airgap between each magnet.

G501 G502

Impulsion Wheelfor G501

Impulsion Wheelfor G502

Signal utilization

When this signal is compared to thetransmission input RPM signal, the controlmodule calculates the output RPM of themulti-disc clutches K1 and K2, and canidentify the clutch slippage. Once theslippage is known, the control moduleregulates the opening and closing of theclutches. This signal is also used to monitorthe currently selected gear in thetransmission. By comparing this signal tothe output RPM sensor signal, the controlmodule can verify that the correct gear isengaged.


In case of a signal failure, the affectedtransmission circuit is closed.

In case of sensor G501 failure, it is onlypossible to drive in 2nd gear.

In case of sensor G502 failure, it is onlypossible to drive in 1st and 3rd gear.

A strong magnet will destroy theimpulsion wheel.

S308_026c

S308_010a

Sensors

S308_106

42

Sensors

Sender 1 for Transmission OutputRPM G195 and Sender 2 forTransmission Output RPM G196

The sensors G195 and G196 are located inthe Mechatronics and are permanentlymounted on the control module.

Like all other RPM sensors in thistransmission, these sensors are Hall effectsensors. Both sense the same impulsionwheel on Output Shaft 2.

The two sensors are placed next to eachother and are protected by a housing. As aresult, two opposite signals are generated.If the signal of sensor G195 is “high”, thesignal of sensor G196 is “low”.

G195 G196

S308_026a G196G195

ImpulsionWheel

S308_050

Signal utilization

With the detailed signals, the controlmodule can identify the vehicle speed andthe direction of travel. The direction of travelis identified by comparing the signalsagainst each other. When a modification oftravel direction occurs, the signals come inopposite order in the control module.


In case of signal failure, the control moduleuses the vehicle speed signal and the traveldirection signal from the ABS controlmodule.

43

Sender 1 G193 and Sender 2 G194for Hydraulic Pressure, AutomaticTransmission

The pressure sensors G193 and G194 arelocated in the electro-hydraulic control unitof the Mechatronics.

The same pressure that acts on the multi-disc clutch K1 acts on Sender 1 G193. Themulti-disc clutch K2 pressure acts onSender 2 G194.

Parallel Plates Ceramic Membrane

SubstrateS308_107G193

G194

S308_031


In case of failure of the pressure signal, or ifthe pressure does not build up, thecorresponding transmission circuit isclosed. The transmission can only beoperated in 1st and 3rd gear, or in 2nd gear.

S308_108

Sensors

Pressure sensor function

The pressure sensor consists of a pair ofelectrically conductive parallel plates. Theupper plate is mounted on a ceramicmembrane, which is deflected according tothe pressure variation. The other plate isrigidly coupled to a ceramic substrate. Thissubstrate does not react to the pressurevariation.

The upper membrane is bent according tothe pressure variations, and the distancebetween the plates varies accordingly. As aresult, a reliable signal is produced as afunction of the transmission fluid pressure.

Signal utilization

With these signals, the Mechatronicselectronic control module can identify thehydraulic pressure acting on the respectivemulti-disc clutch. Precise hydraulic pressureis required for the control module toregulate the multi-disc clutches.

44

Sensors

Multi-plate Clutch Oil TemperatureSensor G509

The Multi-Plate Clutch Oil TemperatureSensor G509 is integrated with the Sensorfor Transmission RPM G182. It measuresthe temperature of the transmission fluidleaving the multi-disc clutches. The multi-disc clutches generate more heat than anyother component in the transmission, andthe transmission fluid leaving them mustbe monitored accurately.

This sensor is built so that it can measurethe temperature very quickly and veryprecisely. It can record temperatures from –55°C to +180°C (-67°F to 356°F).

G509

S308_056

Signal utilization

With the signals from temperature sensorG509, the control module regulates theamount of clutch cooling fluid and initiatesother measurements to protect thetransmission.


In case of signal failure, the control moduleuses the signals from sensors G93 andG510 as replacement signals.

45

Transmission Fluid TemperatureSensor G93 and Control ModuleTemperature Sensor G510

Sensors G93 and G510 are integrated intothe Mechatronics unit, which is surroundedby transmission fluid. Excessive heat in thetransmission fluid can damage theMechatronics.

These two sensors measure the temperatureof the Mechatronics and the fluidsurrounding it. As a result, transmissionfluid temperature increases can bedetected early enough to prevent a rapidincrease in the Mechatronics temperature.

.

G93

G510

S308_026d

Signal utilization

Both sensor signals are used to measurethe Mechatronics temperature.

In addition, based on the sensor signals, awarm-up control program is started.

Both sensors are used to check each other.


When temperature reaches 138°C (280°F),the Mechatronics initiates a reduction inengine torque. At temperatures above145°C (293°F), the multi-disc clutches areno longer provided with fluid pressure andthe clutches open.

Sensors

46

Sensors

Gear Position Distance Sensors 1to 4 G487, G488, G489, G490

These Hall effect position sensors arelocated in the Mechatronics. Along with themagnets and the gearshift forks, theyproduce a signal allowing the controlmodule to know the position of the gearactuator.

Each position sensor monitors the positionof a gear actuator/gearshift fork, whichallows a decision between two gears :

• G487 for gears 1/3

• G488 for gears 2/4

• G489 for gears 6/R

• G490 for gears 5/N

G487 G488

G489G490

S308_025

Signal utilization

Once it has received the exact position, thecontrol module lets the gear actuator usethe transmission fluid pressure to shiftgears. Position Sensor

Magnet

S308_048


If a position sensor fails to provide a signal,the affected transmission circuit is closed.The gears in the affected transmissioncircuit can no longer be used.

47

Selector Lever Sensor SystemControl Module J587

The Selector Lever Sensor System ControlModule J587 is integrated in the selectorlever. It functions simultaneously as acontrol module and as two separatesensors. As a control module, it works tocontrol the solenoid for the selector leverinterlock. The selector lever lighting isintegrated.

At the same time, it contains a Hall effectsensor to recognize the position of theselector lever and a Hall effect sensor torecognize the Tiptronic controls.

The signals for selector lever position andfor Tiptronic are sent to the Mechatronicsand to the control module for application ofthe shift table.

Hall Sensor forTiptronic position

Selector Lever SensorSystem Control Module J587

Hall sensors S308_041

Sensors

48

Actuators

Pressure Control Valve 3 N217(Main Pressure Valve)

The Pressure Control Valve 3 N217 islocated in the electro-hydraulic control unitof the Mechatronics. It is a modulationvalve. The main pressure in theMechatronics hydraulic system is regulatedby this valve.

The most important factor in computingmain pressure is clutch pressure, whichdepends on engine torque.

Engine temperature and engine speed areused to correct the main pressure.

The control module continually adjusts themain pressure based on current conditions.

N217

S308_054_1


If the pressure control valve is defective,the maximum main pressure will be used.As a result, fuel consumption may increaseand gearshifts may become harsh.

49

Pressure Control Valve 1 N215 andPressure Control Valve 2 N216(Clutch Valves)

The Pressure Control Valves N215 andN216 are located in the electro-hydrauliccontrol unit of the Mechatronics.

They are modulation valves and producethe control pressure for the multi-discclutches – Pressure Control Valve N215 formulti-disc clutch K1 and Pressure ControlValve N216 for multi-disc clutch K2.

Engine torque is the basis for thecomputation of clutch pressure. The controlmodule adjusts clutch pressure based onthe actual friction coefficient of the multi-disc clutches.

N215

N216

S308_054_4


In case of failure of a pressure controlvalve, the corresponding transmissioncircuit is closed. This failure will bedisplayed in the instrument panel insert.

Actuators

50

Actuators

Pressure Control Valve 4 N218(Coolant Valve)

The Pressure Control Valve N218 is locatedin the electro-hydraulic control unit. It is amodulation valve and controls a hydraulicslide valve to regulate the volume of clutchcooling fluid. To control the valve, thecontrol module uses the signal from theMulti-Plate Clutch Oil Temperature SensorG509.

N218

S308_054_2


If the pressure control valve cannot beactuated, the maximum cooling fluidvolume flows through the multi-discclutches. In case of low outsidetemperature, this could result in problemsshifting gears as well as a higher fuelconsumption.

51

Solenoid Valves 1 N88, 2 N89, 3N90 and 4 N91 (Gear ActuatorValves)

The four solenoid valves are located in theelectro-hydraulic control unit of theMechatronics. These are ON/OFF valves.They regulate all fluid pressure of themultiplexer slide valves for the gearactuators.

When de-energized, the solenoid valves areclosed and no fluid pressure is provided tothe gear actuators.

• Solenoid Valve 1 N88 controls the fluidpressure to shift the 1st and 5th gears

• Solenoid Valve 2 N89 controls the fluidpressure to shift 3rd gear and Neutral

• Solenoid Valve 3 N90 controls the fluidpressure to shift 2nd and 6th gears

• Solenoid Valve 4 N91 controls the fluidpressure to shift 4th gear and Reverse

N90

N89

N88

N91

S308_054_13


In case of failure of a solenoid valve, thecorresponding transmission circuit,containing the corresponding gear actuator,will be closed. The vehicle can only bedriven in 1st and 3rd gears, or only in 2nd

gear.

Actuators

52

Actuators

Solenoid Valve 5 N92 (MultiplexerValve)

The Solenoid Valve 5 N92 is located in theMechatronics electro-hydraulic control unit.It controls the multiplexer in the hydrauliccontrol unit.

When the solenoid valve is activated, gears2, 4 and 6 can be shifted. When thesolenoid valve is deactivated, gears 1, 3, 5,and Reverse can be shifted.

N92

S308_054_11


The multiplexer slide valve remains in itsresting position. It can no longer beactivated by fluid pressure.

Incorrect gear shifting may occur. It is alsopossible that the vehicle will not engageany gear.

53

Pressure Regulating Valve 5 N233and Pressure Regulating Valve 6N371 (Safety Valves)

Pressure Regulating Valves N233 and N371are housed in the Mechatronics hydraulicmodule. They are modulation valves. Theyregulate the safety valves inside theMechatronics valve body.

In case of a safety related failure in atransmission circuit, the safety valve cutsthe hydraulic pressure of the correspondingtransmission circuit.

Pressure Regulating Valve 5 N233 controlsthe safety slide valve in transmissioncircuit 1. Pressure Regulating Valve 6 N371controls the safety slide valve intransmission circuit 2.

N371 N233

S308_054_6a


In case of failure of a pressure controlvalve, it is no longer possible to shift anygear in the corresponding transmissioncircuit.

If transmission circuit 1 shuts down, it isonly possible to drive in 2nd gear.

If transmission circuit 2 shuts down, it isonly possible to drive in 1st or 3rd gear.

Actuators

54

9

31

N89N88

A

J329

v

Functional Diagram

A – BatteryE313 – Selector LeverF4 – Back-up Light SwitchF319 – Selector Lever Park Position Lock SwitchG93 – Transmission Fluid Temperature SensorG182 – Sensor for Transmission RPMG193 – Sender 1 for Hydraulic PressureG194 – Sender 2 for Hydraulic PressureG195 – Sender for Transmission Output RPMG196 – Sender 2 for Transmission Output RPMG487 – Gear Position Distance Sensor 1G488 – Gear Position Distance Sensor 2G489 – Gear Position Distance Sensor 3G490 – Gear Position Distance Sensor 4G501 – Driveshaft 1 Speed SensorG502 – Driveshaft 2 Speed SensorG509 – Multi-plate Clutch Oil Temperature SensorG510 – Temperature Sensor (in Control Module)J… – Engine control moduleJ329 – Voltage Supply Terminal 15 (B+) RelayJ519 – Vehicle Electrical System Control ModuleJ527 – Steering Column Electronic Systems Control

ModuleJ587 – Selector Lever Sensor System Control ModuleJ743 – Direct Shift Gearbox (DSG) MechatronicsN88 – Solenoid Valve 1N89 – Solenoid Valve 2N90 – Solenoid Valve 3N91 – Solenoid Valve 4N92 – Solenoid Valve 5N110 – Shift Lock SolenoidN215 – Pressure Control Valve 1 for Automatic TransmissionN216 – Pressure Control Valve 2 for Automatic TransmissionN217 – Pressure Control Valve 3 for Automatic TransmissionN218 – Pressure Control Valve 4 for Automatic TransmissionN233 – Pressure Control Valve 5 for Automatic TransmissionN371 – Pressure Control Valve 6 for Automatic Transmission

55

S308_100

a – Terminal 30 over safety switch SC21– K-Wire– CAN Drivetrain high– CAN Drivetrain low

Functional Diagram

AB

C

31

J519

J743

N91N90 N92 N215 N216

J...

G93 G195 G501

G510 G196 G502

G487 G489

G488 G490

N217 N218

N233 N371

F4

G193 G194

x

G182 J587E313

J527

v a

L101 N110 F319J... J...

G509A

x

y

y

B C

56

CAN-Databus-Links

CAN-Databus-Links

The schematic below shows theMechatronics links for the Direct ShiftGearbox in the CAN Databus structure ofthe vehicle.

J104 – ABS Control module with EDL

J248 – Diesel Direct Fuel Injection (DFI)Engine Control Module

J285 – Control Module with Indicator Unitin the Instrument Panel Insert

J519 – Vehicle Electrical System ControlModule

J527 – Steering Column ElectronicSystems Control Module

J533 – Data Bus On-Board DiagnosticInterface

J587 – Selector Lever Sensor SystemControl Module

J623 – Engine Control Module (ECM)

J743 – Direct Shift Gearbox (DSG)Mechatronics

Diagnostic connector

CAN-Data bus “Drivetrain”

CAN-Data bus “Comfort”

S308_080

57

Diagnostic

Diagnostic

The vehicle diagnostic, test, andinformation system VAS 5051 provides thefollowing operating modes:

• Guided Fault Finding

• Guided Functions

“Guided Fault Finding” operating mode

In the “Guided Fault Finding” mode, theDirect Shift Gearbox defines a test planusing sensors, actuators, and theMechatronics.

Sensors:

G93 – Transmission Fluid TemperatureSensor

G182 – Sensor for Transmission RPMG193 – Sensor 1 for Hydraulic PressureG194 – Sensor 2 for Hydraulic PressureG195 – Sender for Transmission Output

RPMG196 – Sender 2 for Transmission Output

RPMG487 – Gear Position Distance Sensor 1G488 – Gear Position Distance Sensor 2G489 – Gear Position Distance Sensor 3G490 – Gear Position Distance Sensor 4G501 – Driveshaft 1 Speed SensorG502 – Driveshaft 2 Speed SensorG509 – Multi-Plate Clutch Oil Temperature

SensorG510 – Temperature Sensor (in Control

Module)

Actuators:

N88 – Solenoid Valve 1





N110 – Shift Lock Solenoid

N215 – Pressure Control Valve 1






Mechatronics:

J743 – Mechatronics gear monitoring

J743 – Mechatronics shifting monitoring

J743 – Mechatronics power supply voltage

“Guided Functions” operating mode

In the “Guided Functions” operating mode,the Direct Shift Gearbox executes a testplan to test the oil levels.

Pay attention to the instructions in VAS5051 when testing sensors andactuators.

58

Service

Special Tools

A new special tool, the VAS 6252, has beencreated to check and adjust the fluid level ofthe Direct Shift Gearbox.

This tool has a quick release coupling toeasily control the fluid level.

A three-way valve on the fluid bottleconnection allows for easy replacement ofthe bottle.

Adapter Three-way valve

Quick coupling

S308_110

Be careful not to mix different types oftransmission fluids. Poor operation orinternal damage can result.

59

Notes

60

Notes

61

An on-line Knowledge Assessment (exam) is available for this Self-Study Program.

The Knowledge Assessment may or may not be required for Certification.

You can find this Knowledge Assessment at:

www.vwwebsource.com

From the vwwebsource.com Homepage, do the following:

– Click on the Certification tab

– Type the course number in the Search box

– Click “Go!” and wait until the screen refreshes

– Click “Start” to begin the Assessment

For Assistance, please call:

Certification Program Headquarters

1 – 877 – CU4 – CERT(1 – 877 – 284 – 2378)

(8:00 a.m. to 8:00 p.m. EST)

Or, E-Mail:

[email protected]

Knowledge Assessment

Volkswagen of America, Inc.

3800 Hamlin Road

Auburn Hills, MI 48326

Printed in U.S.A.

May, 2004

Documents

DSG Transmission