Audi A3 2009 2010 User Manual

Service Training

Audi New Technology 2009 – 2010

Self-Study Program 990193

Audi of America, LLC Service Training Printed in U.S.A. Printed 11/2009 Course Number 990193

All rights reserved. Information contained in this manual is based on the latest information available at the time of printing and is subject to the copyright and other intellectual property rights of Audi of America, LLC., its afﬁ liated companies and its licensors. All rights are reserved to make changes at any time without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, nor may these materials be modiﬁ ed or reposted to other sites without the prior expressed written permission of the publisher.

All requests for permission to copy and redistribute information should be referred to Audi of America, LLC.

Always check Technical Bulletins and the latest electronic repair literature for information that may supersede any information included in this booklet.

Table of Contents

R8 with 5.2L V10 FSI Engine . . . . . . . . . . . . . . . . . . . . . . . . . 1

Packaged Ultrasonic Level Sensor (PULS) . . . . . . . . . . . .17

0B5 S Tronic Transmission . . . . . . . . . . . . . . . . . . . . . . . . . .20

Sport Differential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Indirect Tire Pressure Monitoring . . . . . . . . . . . . . . . . . . . .69

MMI 3G . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73

Knowledge Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . .93

The Self-Study Program provides introductory information regarding the design and function of new models, automotive components or technologies.

The Self-Study Program is not a Repair Manual! All values given are intended as a guideline only. Refer to the software version valid at the time of publication of the SSP.

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

Reference Note

Notes

R8 with 5.2L V10 FSI Engine

Audi continues to build on its leadership position in the high-performance sports car segment with the R8 5.2L V10 FSI quattro. The top-of-the-line model of the R8 model series was developed jointly with quattro GmbH. Its ten-cylinder engine develops 525 hp (386 kW) which is capable of delivering breathtaking performance.

Audi technologies such as quattro permanent all wheel drive, lightweight aluminum body (ASF) and innovative all-LED lights propel the R8 5.2L V10 to the top of its competitive ﬁ eld.

At a glance:

Engine

– Newly developed V10 with 5.2 liters displacement, FSI

direct injection and dry sump lubrication

– Superior performance 525 hp (386 kW) and 390 lb ft

(530 Nm) of torque

Power train

– Six-speed manual transmission; optional sequential

R tronic with paddle shifters on steering wheel and “Launch Control” function

– quattro permanent all wheel drive with rear-wheel bias

990193_100

Chassis

– Dual aluminum wishbone suspension – High-performance brakes, optional with ceramic discs – 19-inch wheels – Audi magnetic ride adaptive suspension

Body and design

– Lightweight, extremely rigid aluminum ASF body

weighs only 436 lb (210 Kg) – Spacious interior and high level of everyday utility – Exterior and interior design with distinctive new

elements – All-LED lights as standard

R8 with 5.2L V10 FSI Engine

Technical Speciﬁ cations

Engine:

Naturally aspirated 5.2 liter V10 spark ignition engine with FSI, 90° cylinder angle, 4-valve per cylinder,

Type

double overhead camshafts (DOHC), intake manifold with charge movement flaps

8700 rpm

rpm

Arrangement

Displacement

Compression ratio

Fuel requirement

Horsepower

Torque

Engine design:

Cylinder block

Connecting rods

Pistons

Crankcase

Crankshaft

Cylinder head

Valve train

Firing order

Cooling system

Lubrication system

Fuel injection

Emission system

Electrical system:

Battery

Alternator

Drive train:

Transmission

Gear ratios: 1st

Reverse

Final drive

Center differential

Steering:

Turning circle (curb to curb)

Mid-mounted, longitudinal

Bore

Stroke

3.65 in (92.8 mm)

12.5 : 1

Premium unleaded

525 hp (386 kW) @ 8000 rpm

391 lb ft (530 Nm) @ 6500 rpm

Aluminum alloy incorporating silicon crystals

Forged steel / large ends cracked

Aluminum

High strength aluminum alloy casting

Forged steel, 5 main bearings

Aluminum alloy casting

Chain-driven DOHC, continuous intake and exhaust camshaft adjustment

1–6–5–10–2–7–3–8–4–9

Water-cooled, thermostatically controlled radiator fan

Dry sump oil system

FSI

Two metal primary catalytic converters, two metal main catalytic converters, four heated oxygen sensors, secondary air injection system

Super Plus ROZ 98 (Premium unleaded — 9 AKI)

Fuel

110 amp/hour

14.0 volts 190 amp

6-speed manual with launch control / optional R tronic with launch control

Manual R tronic

Type

2nd

3rd

4th

5th

6th

3.077 3.077

Viscous clutch

Hydraulically assisted rack-and-pinion

Type

17.3

Ratio

3.33 in (84.5 mm)

317.6 cu in (5,204 ccm)

4.373

2.709

1.925

1.502

1.239

1.035

3.713

38.7 ft (11.8 m)

2.709

1.925

1.502

1.239

1.035

4,373

3.713

R8 with 5.2L V10 FSI Engine

Suspension:

Double aluminum wishbone

Front

Double aluminum wishbone

Rear

Brakes:

Service brake: Discs/calipers

Parking brake

Wheels (standard only):

Tire (standard only):

Body:

Corrosion protection

Capacity:

Engine oil

Fuel tank

Reserve

Cooling system

Exterior dimensions: [see next page]

Interior dimensions:

Seating capacity

EPA class

Head room

Shoulder room

Leg room

Interior volume (EPA)

Luggage capacity trunk / behind seats

Performance:

0 - 60 mph

0 - 100 km/h

0 - 200 km/h

Top speed

Lateral acceleration

Fuel economy (EPA estimate): Manual R-tronic

Highway

Combined

Disc brakes, internally vented / eight piston calipers at front, 4 piston calipers at rear

Front

14.4 in (365 mm)

Rear

14.4 in (365 mm)

Mechanically actuated at the rear wheels

Size

Front: 8.5J x 19, Rear: 11J x 19 Alloy

Size

Front: 235/35 91Y, Rear: 295/30 100Y

Material

Multi-step anti-corrosion protection

Audi Space Frame (ASF)

12.7 qt (12.0L)

23.8 gal (90L)

2.6 gal (10L)

5.3 gal (24.0l)

n/a

3.5 cu ft (100L) / 3.18 cu ft (90L)

5.2 FSI quattro - manual 5.2 FSI quattro - R tronic

3.7 seconds 3.7 seconds

3.9 seconds 3.9 seconds

12.0 seconds 12.0 seconds

196 mph (316 km/h) 196 mph (316 km/h)

1.2 g

12.0 mpg 13.0 mpg

City

20.0 mpg 20.0 mpg

15.0 mpg 15.0 mpg

R8 with 5.2L V10 FSI Engine

Dimensions

49.2 in (1252 mm)

64.4 in (1638 mm)

75.9 in (1930 mm)

39.4 in (1003 mm)

37.7 in (958 mm)

104.3 in (2650 mm)

174.6 in (4435 mm)

62.7 in (1595 mm)

79.8 in (2029 mm)

30.7 in (782 mm)

54.8 in (1392 mm)

990193_101

Like the R8 4.2L, the R8 5.2L V10, uses an Audi Space Frame of aluminum and ultra-light magnesium. It is produced largely by hand in the Neckarsulm manufacturing plant of quattro GmbH.

Maximum precision and the use of the most advanced joining techniques are employed. This includes: 325 ft (99 meters) of welding seams, 782 rivets, and 308 selftapping screws that hold the body together.

A fully automatic measuring system checks the dimensions of every body with precision in the one-tenth of a millimeter range.

R8 with 5.2L V10 FSI Engine

990193_102

990193_103

Casting (aluminum)

Section (aluminum)

Sheet metal (aluminum)

Magnesium

R8 with 5.2L V10 FSI Engine

5.2L V10 FSI Engine

The V10 for the R8 has a total displacement of 5,204 cc and is designed for high-performance.

Speciﬁ c power output for the R8 V10 is 100.9 hp per liter of displacement. Each horsepower of the engine only needs to move 6.81 lb (3.09 kilograms) of weight. When equipped with a manual transmission, the vehicle only weighs 3571 lb (1,620 kilograms).

The 10-cylinder layout is an ideal design solution for maximum performance. Compared to a V8 with the same displacement, a V10 has smaller and lighter pistons and connecting rods, which makes it a free-revving engine. Compared to a V12, it has fewer components, resulting in lower moving masses and less internal friction. Even with all attached components, the 10-cylinder engine is only 25 inches (646 mm) long, 29 inches (737 mm) wide, and 27 inches (696 mm) high.

990193_104

R8 with 5.2L V10 FSI Engine

Speciﬁ cations

hp (kW) lb ft (Nm)

600 (450)

540 (400)

470 (350)

400 (300)

340 (250)

270 (200)

200 (150)

130 (100)

70 (50)

530 (720)

470 (640)

410 (560)

350 (480)

300 (400)

230 (320)

180 (240)

120 (160)

Power output

Torque

60 (80)

990193_110

Displacement:

Horsepower:

Maximum torque:

Maximum rpm:

Fuel requirement:

317.8 cubic inches (5204 cc)

525 hp SAE (386 kW) @ 8000 rpm

391 lb ft (530 Nm) @ 6500 rpm

8700

Premium unleaded

990193_113

Type:

Arrangement:

Bore:

Stroke:

Compression ratio:

Cylinder block:

Connecting rods:

Pistons:

Crankcase:

Cylinder head:

Valve train:

Firing order:

Cooling system:

Lubrication system:

Fuel injection/ignition system:

Emission system:

Fuel:

5.2 liter V10 spark-ignition with FSI, 90° cylinder angle, 4 valve technology, DOHC, intake manifold with charge movement flaps, naturally aspirated

Longitudinal, mid-engine installation

3.33 inches (84.5 mm)

3.65 inches (9.28 mm)

12.5:1

Aluminum alloy

Forged steel

Aluminum

High strength aluminum alloy casting

Aluminum alloy

DOHC chain driven, continuously variable intake and exhaust camshaft adjustment

1-6-5-10-2-7-3-8-4-9

Water cooled, thermostatically controlled radiator fans

Dry sump oil system

FSI direct injection

Two metal primary converters, two main converters, four heated O

Super Plus ROZ 98 / Premium unleaded (91 AKI)

sensors, secondary air system

R8 with 5.2L V10 FSI Engine

The crankcase is produced by a low-pressure die-casting method. It is made from hypereutectic aluminum-silicon alloy — a high-tech material that combines low weight with high strength. The high silicon content of this alloy gives the cylinder walls the necessary wear resistance to withstand very high average piston velocity.

The bedplate design — the lower bearing brackets for the crankshaft are integrated into a single frame — provides the crankcase with maximum rigidity and optimal vibration behavior. Integrally cast iron bearing brackets reduce thermal expansion of the aluminum housing and minimize play in the main crankshaft bearings. The forged crankshaft and forged-steel con rods combine high strength with low weight. The pistons are forged of a high-strength aluminum alloy.

431_046

With the dry-sump lubrication system there is no oil pan. The engine has an intake module connected directly to the external oil pump via intake ports.

This intake module does not have a large oil reservoir. Instead it serves as a bafﬂ e plate and collects the outﬂ owing oil generated by the rotation of the crankshaft.

431_074

The crankshaft has been designed as a common-pin type crank pin, and not a split-pin type as on the 5.2L V10 engine used in the Audi S6.

Common-pin

crankshaft

R8 with 5.2L V10 FSI Engine

431_066

Split-pin

431_044

crankshaft

The camshafts, as well as the oil pump, the water pump, and parts of the accessory sub-systems, are driven by maintenance-free chains located on the rear wall of the engine. All four camshafts are adjustable through a 42° crank angle, which provides a wide range of control timing. The valves are actuated by roller-mounted cam followers. The exhaust valves are subject to a high thermal load and are lined with sodium to assist in cooling.

431_042

R8 with 5.2L V10 FSI Engine

Dry Sump Lubrication System

The oil pump module is external to the engine and is chain-driven. The pump consists of a suction and feed pump for ﬁ lling the oil reservoir, and a suction and pressure pump for supplying oil to the engine.

The oil pump and coolant pump are paired to form a single unit, so they can only be replaced as a unit.

Only the thermostat housing and integrated coolant thermostat can be replaced separately.

990193_105

Oil return from

right cylinder head

To main oil port

Water pump

R8 with 5.2L V10 FSI Engine

431_025

Legend

1 Crankshaft chamber 5

2 Chain case return line

3 Oil return from right cylinder head

4 Oil return from left cylinder head

5 Crankshaft chamber 4

6 Crankshaft chamber 3

7 Crankshaft chamber 2

8 Crankshaft chamber 1

9 To oil thermostat

10 To main oil port

11 From oil reservoir

12 Suction pump

13 Pressure pump

14 Crankcase divider

R8 with 5.2L V10 FSI Engine

In combination with an oil-to-water heat exchanger located in the inner V of the engine, the 5.2L V10 uses a thermostatically controlled airﬂ ow-type oil cooler to regulate engine oil temperature. It is mounted behind the left side-blade the body.

When the engine oil is cold, the re-circulating, extracted oil is pumped into the oil thermostat housing. When the thermostat is in a closed state, it seals off the inlet leading to the oil cooler, while the oil in the thermostat housing is redirected to the oil reservoir.

When the temperature of the oil exceeds 212°F (100°C), the oil thermostat opens the inlet to the oil cooler.

An expanding element in the thermostat exerts pressure against the thermostat housing. Due to the pressure of the expanding element, the thermostat is displaced against the force of a spring, opening the channel, and simultaneously closing off the inlet leading directly to the oil reservoir.

Oil ﬂ ows through this port and into the oil cooler, returning from there to the oil thermostat housing before entering the oil reservoir.

Oil cooler, located

behind left side blade

990193_107

Notes

R8 with 5.2L V10 FSI Engine

Mass Air Flow Sensor G70 Intake Air Temperature Sensor G42

Throttle Position Sensor G79 Accelerator Pedal Position Sensor -2- G185

Engine Speed Sensor G28

Knock Sensors -1- and -2- G61, G62

Fuel Pressure Sensor G247

Camshaft Position Sensor G40 Camshaft Position Sensor -3- G300

Throttle Valve Control Module J338 Throttle Drive Angle Sensors -1- and -2- G187, G188 Throttle Drive G186

Engine Coolant Temperature Sensor G62

Low Fuel Pressure Sensor G410

Intake Manifold Runner Position Sensor G336

Heated Oxygen Sensor G39 Oxygen Sensor Behind 3-Way Catalytic Converter G130 Heated Oxygen Sensor -2- G108 Oxygen Sensor -2- Behind 3-Way Catalytic Converter G131

Powertrain

CAN-Bus

Engine Control

Module J623

Brake Booster Pressure Sensor G294

Brake Light Switch F Brake Pedal Switch F47

Additional Signals: Oil Temperature Sensor -2- G664 Secondary Injection Sensor -1- G609 Clutch Position Sensor G476 Cruise Control ON/OFF Park/Neutral Signal Terminal 50 Wake Up Signal from Driver’s Door Switch via J393

Mass Air Flow Sensor G246 Intake Air Temperature Sensor -2- G299

Camshaft Position Sensor -2- G163 Camshaft Position Sensor -4- G301

Throttle Valve Control Module -2- J544 Throttle Drive Angle Sensors -1- and -2- G297, G298

Knock Sensors -3- and -4- G198, G199

Heated Oxygen Sensor -3- G285 Oxygen Sensor -3- Behind 3-Way Catalytic Converter G287 Heated Oxygen Sensor -4- G286 Oxygen Sensor -4- Behind 3-Way Catalytic Converter G288

Intake Manifold Runner Position Sensor -2- G512

Secondary Air Injection Sensor -2- G610 Fuel Pressure Sensor -2- G624

Engine Control

Module -2- J624

R8 with 5.2L V10 FSI Engine

Fuel Pump Control Module J538 Transfer Fuel Pump G6

Ignition Coils 1-5 with Power Output Stage N70, N291, N292, N323, N127; Cylinders 1-5

Fuel Metering Valve N290

Evaporative Emission Canister Purge Regulator Valve N80

Right Electro-Hydraulic Engine Mount Solenoid Valve N145

Intake Manifold Runner Control (IMRC) Valve N316

Starter Relay J53; Starter Relay -2- J695

Leak Detection Pump V144

Exhaust Flap Valve -1- N321

Fuel Injectors N30, N31, N32, N33, N83 Cylinders 1-5

Data Link

Connector

990193_114

Camshaft Adjustment Valve -1- N205 Camshaft Adjustment Valve -1- (exhaust) N318

Throttle Drive (for EPC) G186

Coolant Recirculation Pump Relay J151 After-Run Coolant Pump V51

Oxygen Sensor Heater Z19; Oxygen Sensor -1- Behind 3-Way Catalytic Converter Heater Z29; Oxygen Sensor

-2- Heater Z28; Oxygen Sensor -2- Behind 3-Way Catalytic Converter Heater Z30

Secondary Air Injection Pump Relay J299 Secondary Air Injection Pump Motor V101 Secondary Air Injection Solenoid Valve N112

Brake Booster Relay J569 Brake System Vacuum Pump V192

Engine Component Power Supply Relay J757 Engine Control Module Power Supply Relay J271

Additional Signals: Coolant Fan Control (FC) Control Module J293 Coolant Fan Control (FC) Control Module -2- J671

Ignition Coils 6-10 with Power Output Stage N324-N328 Cylinders 6-10

Secondary Air Injection Pump Relay -2- J545; Secondary Air Injection Pump Motor -2- V189; Secondary Air Injection Solenoid Valve -2- N320

Camshaft Adjustment Valve -2- N208 Camshaft Adjustment Valve -2- (exhaust) N319

Fuel Injectors N84-N86, N299-N300; Cylinders 6-10

Oxygen Sensor -3- Heater Z62; Oxygen Sensor -3- Behind 3-Way Catalytic Converter Heater Z64; Oxygen Sensor

-4- Heater Z63; Oxygen Sensor -4- Behind 3-Way Catalytic Converter Z65

Evap. Emission Canister Purge Regulator Valve -2- N333

Fuel Metering Valve -2- N402

Left Electro-Hydraulic Eng. Mount Solenoid Valve N144

Throttle Drive -2- G296

R8 with 5.2L V10 FSI Engine

Distinguishing Features of the 5.2L V10 R8

Audi is the world’s ﬁ rst automaker to use LEDs for high beam, low beam, daytime running lights, and turn signals. In this highly complex technology, lens and reﬂ ector systems, intelligent ballasts, and fan driven coolers interact. Although the LEDs emit cool light, they heat up, and their temperature must be kept within a deﬁ ned range.

With a color temperature of 6,000 Kelvin, the LED light closely resembles white daylight, which is less tiring to the eyes when driving at night.

Excellent light distribution and virtually unlimited LED service life are additional beneﬁ ts. Their energy consumption is also substantially lower than halogen lights.

The rear fascia of the R8 5.2L V10 features high-gloss black as the dominant color.

LEDs mounted in tubular housings create a threedimensional lighting effect.

The rear fascia air outlets have only two cross braces, and the exhaust system terminates in two large, oval tailpipes.

The fully enclosed underbody ends in a diffuser with a pronounced upward sweep.

The rear spoiler automatically deploys at 62 mph (100 km/h.)

990193_112

990193_111

Packaged Ultrasonic Level Sensor (PULS)

New Oil Level Sensor

A new generation engine oil level sensing system has been introduced by Audi. It is referred to in the technical literature and VAS Scan Tool as: PULS — Packaged Ultrasonic Level Sensor. Vehicles using this system can be identiﬁ ed by the absence of an oil dipstick.

PULS operates on an ultrasonic principle. Ultrasound pulses generated by the oil level sensor are reﬂ ected by the oil-air boundary layer. This type of level sensor replaces the older Thermal Oil Level Sensor (TOLS) that used the hot-wire principle.

Upper

oil pan

With PULS, oil level is calculated by the engine control module, which factors the difference between transmitted and reﬂ ected pulses of the oil level sensor, and the speed of sound.

The driver can view oil level information via the MMI under the heading CAR. In addition, minimum and maximum oil level warnings are displayed in the Driver Information Display of the instrument cluster.

Virtual cylinder

0.7 in (20 mm) diameter

free of reﬂ ective surfaces

Oil level

sensor

Lower

oil pan

Static

measurement

range

2.9 – 4.7 in

(75 – 120 mm)

measurement

0.6 – 2.9 in

(15 – 75 mm)

Ultrasonic signals are processed electronically by circuitry in the oil level sensor and are transmitted to the instrument cluster through a Pulse Width Modulated (PWM) signal.

Dynamic

range

Zero reference

point of system

411_100

Advantages of the PULS versus a Thermal Oil Level System (TOLS):

– The sensor signal is available quickly (approx. 100 ms

for ignition ON) – Low electrical power consumption (approx. 0.5A)

Packaged Ultrasonic Level Sensor (PULS)

Oil Level Scale

The Engine Control Module calculates oil level in the engine. This information is transmitted to the Powertrain CAN-bus where it is read by the instrument cluster and MMI, which then pass this information on to other subsystems via Data Bus On Board Diagnostic Interface J533.

Because the dipstick has been eliminated, the customer can only check the oil level via the instrument cluster or MMI displays.

Oil level scale

T40178

Dynamic Measurement

This measurement method is preferred because it provides more accurate results. The measurement process is interrupted when:

– Vehicle acceleration rate is greater than 6.7 mile/hour

seconds (3 meter/sec – Oil temperature is greater than 284°F (140°C) – Engine hood has been opened

)

Checking the oil in the workshop requires special tool T40178. The tool must be calibrated for each individual engine. The adjustment ring is ﬁ rst set to the correct position, then the oil level is read on the oil level scale. The correct setting position value for T40178 can be found in the repair manual maintenance section.

Oil level is calculated both dynamically (vehicle moving) and statically (vehicle stationary).

Adjustment

ring

411_105

Static Measurement

This measurement is performed:

– At ignition ON (however, the signal is transmitted as

soon as the driver’s door is opened in order to obtain

a level signal quickly – Engine speed less than 100 rpm – Engine at standstill for longer than 60 seconds – Engine temperature over 104°F (40°C)

The following criteria are evaluated:

– Engine speed – Longitudinal and transverse acceleration – Engine temperature – Engine Hood Switch F266 position (open/closed) – Number of miles (km) driven since the last opening of

Engine Hood Switch F266 (more than 30 miles [50 km])

– Number of measurement values generated within the

driving cycle

The longitudinal and transverse acceleration values, as well as the parking brake position are also used to determine vehicle status when measurements are made.

Packaged Ultrasonic Level Sensor (PULS)

Oil level can be checked by the customer using the MMI, under the CAR menu.

Oil Level

Engine oil level o.k.

Max

Min

411_096

The following graphics can be displayed in the DIS of the instrument cluster.

Max

Please add max. 1 qt oil. Continued driving possible.

35540

D4 27° F

m 1975.5

Min

411_097

Oil level is o.k.

35540

D4 27° F

In addition, there is a display that indicates overﬁ lling of the system, and a display that indicates if the oil level sensor has failed.

Max

Min

m 1975.5

411_098

Urgent: Please add oil.

35540

D4 27° F

Max

Min

m 1975.5

411_099

0B5 S Tronic Transmission

0B5 7-Speed Dual Clutch Transmission

Following the success of the six-speed S tronic on the Audi A3 and Audi TT models, a seven-speed dual-clutch transmission, combined with the quattro powertrain, is now available for the ﬁ rst time in a longitudinal conﬁ guration.

Speciﬁcations of the 0B5 transmission

Designations Manufacturer: DL501-7Q

Service: 0B5 Distribution: S tronic

Development production Audi AG Ingolstadt

VW plant, Kassel

Type Seven-speed, dual-clutch gearbox;

fully synchronized, electro-hydraulically controlled

Dual clutch Dual oil-cooled multi-plate clutches,

electro-hydraulically controlled

Control Mechatronic system — integrating the hydraulic control module,

electronic control module, some sensors and actuators; sport program and “tiptronic” shift program for manual gear shifting

Ratio spread Up to 8.1 : 1*

The 0B5 S tronic transmission combines the positive features of an automatic transmission with the sportiness and efﬁ ciency of a manual gearbox. It provides extremely short shift times without interruption of tractive power to provide a special driving experience.

Shaft spacing 3.503 in (89.0 mm)

Torque capacity Up to 406.6 lb ft (550 Nm) at 9000 rpm

Weight Approx. 313.0 lb (142 kg), including dual-mass flywheel and

oil fill

* 7th gear is conﬁ gured as an overdrive gear. Top speed is in 6th gear.

Final drive/

differential (forward

of the dual clutch)

Transmission

plate with dual-

mass ﬂ ywheel

0B5 S Tronic Transmission

Vent for ATF system

(hydraulic controls/

dual clutch)

Vent for gear oil system

(gears/transfer case/

front axle drive)

Connection

to ATF cooler

Connection for

ATF, ﬁ ller

and oil level

checking bolt

Mechatronic

module

429_124

Center

differential

Seven-speed

gearbox

assembly

Spur pinion with special tooth

geometry which allows the

shaft to rotate at an angle in

two planes (beveloid gearing)

Oil drip

pans

Bi-planar

angled

side shaft

Gear lever

429_128

Dual clutch

(K1, K2)

Final drive with

welded ring gear

and special tooth

geometry to

accommodate the

angled side shaft

0B5 S Tronic Transmission

Component Parts Overview

Transmission

plate

Dual mass

ﬂ ywheel

Dual clutch

(K1, K2)

Stop

Hydraulic control

(Mechatronic

system)

Connection

module for

ATF cooler

Direct Shift

Gearbox (DSG)

Mechatronic J743

Electric

connection

Oil drain

port

Advantages of Seven Gear Ratios

Seven forward gears provide a wide ratio spread that boosts initial acceleration, while also lowering fuel consumption via the 7th (overdrive) gear.

Gear lever

0B5 S Tronic Transmission

Selector

rail

Oil drip

pan

Gear oil ﬁ ll

and level

checking bolt

Self-locking center differential with 40/60 asymmetric/dynamic torque split. The asymmetric-dynamic power distribution provides sporty and agile driving characteristics with slight emphasis to the rear axle. When needed, the center differential can deliver up to 85% power to the rear axle or a maximum of 65% power to the front axle.

Serviceable

offset depth for

all shaft oil seals

when replaced

429_116

0B5 S Tronic Transmission

Gearbox Design — Function

Drive is transmitted to the dual mass ﬂ ywheel through the transmission plate. From there, torque is transmitted to electro-hydraulically controlled clutches (K1, K2) which operate even or odd numbered gears.

The gear arrangement of the 05B transmission can be viewed as two separate gear boxes.

Sub-Gearbox 1

Odd numbered gears (1, 3, 5, 7) are driven through central input shaft 1 by clutch K1.

Clutch K1

Clutch K2

Sub-Gearbox 2

Even numbered gears (2, 4, 6) and the reverse gear are driven through input shaft 2 (a hollow shaft) by clutch K2.

Power output is through the common output shaft, with torque transmitted directly to the center differential. Torque distribution is approx. 60% to the ﬂ ange shaft connected to the rear axle, and approx. 40% to the spur pinion and side shaft connected to the front axle drive (not shown here).

Input

shaft 2

Transmission

plate

Dual mass

ﬂ ywheel

Design Features of the Dual Clutch

The dual clutch serves two tasks:

– To engage the engine at initial acceleration and to

disengage the engine when stopping

– To shift the gears

The dual clutch was designed so that clutch K1 is located on the outside, making it a larger diameter. This meets the higher demands placed on K1 as the starting clutch (in ﬁ rst gear).

Parking

lock gear

6th gear

4th gear

2nd gear

Reverse (R) gear

Small pressure cylinders and coil spring assemblies on both clutches provide good control during initial acceleration and when changing gears.

Hydraulic pressure equalization is no longer required. Clutch control corrects dynamic pressure build-up caused by centrifugal forces at high engine speeds in any situation.

Gear Shifting Sequence

0B5 S Tronic Transmission

Initial Acceleration

In selector lever position P or N, only 1st gear and reverse are engaged. This allows immediate acceleration from a standing stop. Regardless of whether the driver decides to drive in reverse or to go forward, the correct gears are already pre-selected.

Input

shaft 1

Spur pinion/

output to front

axle (beveloid

gearing)

Shifting

To drive forward, the driver shifts the selector lever into D and drives away in 1st gear. When a deﬁ ned speed threshold of approx. 10 mph (15 km/h) is exceeded, 2nd gear is engaged in sub-gearbox 2 (reverse was previously engaged).

When the shift point for upshifting from 1st to 2nd gear is reached, the gearshift is made by the rapid opening of clutch K1 and simultaneous rapid closing of clutch K2 without any interruption in tractive power. To enhance shift comfort and preserve the clutch, engine torque is reduced during the gearshift (overlap).

The gear shifting process is completed within a few hundredths of a second. 3rd gear is now pre-selected in sub-gearbox 1. The process described above repeats itself alternately during the subsequent gearshifts from 2-3 up to 6-7.

Output to rear

axle differential

1st gear

3rd gear

7th gear

5th gear

Center

differential

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Synchromesh

To facilitate extremely short shift times, all gear synchronizers are carbon coated.

Gears one, two, and three are also triple cone synchronizers due to the high stresses to which they are subjected.

Gears 4, 5, 6, and 7 use single cone synchronizers.

0B5 S Tronic Transmission

Transmission Oil Systems

ATF Oil System

The 0B5 transmission has two separate oil systems.

The ﬁ rst oil system accommodates the dual clutch, Mechatronic system, and oil supply. These components use an ATF developed speciﬁ cally for the 0B5 transmission.

This ATF system enables rapid shifting even at low temperatures, while also lubricating and cooling the dual clutch.

Dual

clutch

ATF

pump

Mechatronic

system

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Gear Oil System

The second oil system incorporates the gear assembly, the transfer case (center differential), and the front axle drive.

Lubrication is by means of a hypoid gear oil with a special oil additive for the center differential. Separating these oil chambers made it possible to design the individual component parts of the transmission optimally. It was not necessary to make any compromises due to conﬂ icting demands on the lubricants.

Note

ATF oil is subject to a ﬁ xed replacement interval (refer to maintenance).

Hypoid gear oil is designed for lifetime use.

Gear

Transfer

case

assembly

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Front axle

differential

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