431

Vorsprung durch Technik www.audi.co.uk Service Training

Audi RS 6

Self-Study Programme 431

All rights reserved. Technical

specifications subject to
change without notice.

Copyright
AUDI AG
N/VK-35
Service.training@audi.de
Fax +49-7132/31-88488

AUDI AG
D-85045 Ingolstadt
Technischer Stand 04/08

Printed in Germany
A08.5S00.47.20
The Audi RS models from quattro GmbH are the ultimate in sportiness, complemented by powerful and elegant
design, exclusive equipment and perfect quality.
The new Audi RS 6 will only be available as an Avant to start with, with the unrivalled combination of 580 bhp and
a maximum 1,660 litres of luggage space. The Audi RS 6 redefines the concept of high performance in the business
class. With its 426 kW (580 bhp), it is the most powerful model in the current Audi range and with the exception of
pure racing cars like the Le Mans-winning Audi R10 TDI, it is the most powerful Audi of all time. By the same token,
it completely outclasses all its competitors in the luxury performance category.
A newly developed V10 engine with FSI direct injection and twin turbochargers, permanent quattro four-wheel drive
and sports suspension with Dynamic Ride Control DRC sets the standard for high-performance cars in the luxury class.

431_015

After reading the Self-Study Programme, you will be able to answer the following questions:

– What are the differences between this engine and the 5.2l V10 engine?

– How does the cooling system with all its radiators, coolers and thermostats work?

– What function does the air filter port in the turbocharger oil return line serve?

– What should be noted regarding the ceramic brake?

– Which modifications to the RS 4 have been incorporated into the Dynamic Ride Control (DRC) system?
Contents

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Occupant protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Engine mechanicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Oil circulation system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Cooling system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Engine management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Automatic gearbox 09E . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Suspension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Dynamic Ride Control – DRC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Wheels and tyres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Brake system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Electrical system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Bus topology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Headlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

The Self Study Programme teaches the design and function of new vehicle models,
new automotive components or new technologies. Reference Note

The Self Study Programme is not a Repair Manual.

All values given should be considered as guidelines, and refer
to the software version valid at the time of preparation of the SSP.

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

Dimensions of the Audi RS 6 Avant

The values given in square brackets are deviations from the Audi A6 Avant.

431_001_1

Max. headroom for driver and front passenger has been increased to 1030 mm.

431_001_2

* Max. headroom

Specifications in millimetres
Dimensions refer to kerb (unladen) weight of vehicle

4
All interior dimensions are otherwise unchanged despite the modification of the boot floor panel.

431_001_3

Length in mm 4928 Inner width, front in mm 1450

Width excl. mirrors in mm 1889 Inner width, rear in mm 1421

Height in mm 1460 Headroom, front in mm 1030

Track width, front in mm 1614 Headroom, rear in mm 978

Track width, rear in mm 1637 Through-loading width in mm 1061

Wheelbase in mm 2846 Load sill heightin mm 630

Kerb weight in kg 2025 Luggage capacity (seats down) in l 565/1660

Max. allowable gross weight in kg 2655 Fuel tank capacity in l 80

Drag coefficient cw 0.35

The saloon version of the Audi RS 6 will be launched at a later date.

5
 Body

Audi RS 6 Avant
Body modifications compared to Audi A6 Avant

7
6
1

431_018

Audi RS 6 saloon
Body modifications compared to Audi S6 saloon

10

7
6
1

431_019
Legend:

1 Wing, front left and right 6 Door outer panel, rear left and right
2 Jack support pad, front left and right 7 Door inner panel, rear left and right
3 Jack support pad, rear left and right 8 Boot floor panel, rear
4 Sidewall frame, left and right 9 Tailgate panel, exterior
5 Wheel arch, rear left and right 10 Tailgate panel, interior

6
 Occupant protection

The Audi RS 6 has the same occupant protection features as the Audi A6 Avant.

431_070

Legend:

E24 Driver side belt switch K19 Seat belt warning system warning lamp
E25 Front passenger side belt switch K75 Airbag warning lamp
E224 Airbag disabling key switch, front passenger side K145 Passenger airbag off warning lamp
(PASSENGER AIRBAG OFF)
G128 Seat occupancy sensor, front passenger side
G179 Side airbag crash sensor, driver side (front door) N95 Airbag igniter, driver side
G180 Side airbag crash sensor, front passenger side N131 Front passenger side airbag igniter 1
(front door) N132 Front passenger side airbag igniter 2
G256 Rear side airbag crash sensor, driver side N153 Driver seat belt tensioner igniter -1-
G257 Rear side airbag crash sensor, front passenger side N154 Front passenger seat belt tensioner igniter -1-
G283 Driver side front airbag crash sensor N199 Side airbag igniter, driver side
G284 Front passenger side front airbag crash sensor N200 Side airbag igniter, front passenger side
N250 Driver side airbag igniter -2-
J234 Airbag control unit N251 Driver side curtain airbag igniter
J285 Control unit with display in dash panel insert N252 Front passenger side curtain airbag igniter
J393 Convenience system central control unit
J533 Data bus diagnostic interface T16 16-pin connector (diagnostic port)
J623 Engine control unit
J655 Battery cut-off relay

7
 Engine mechanicals

5.0l V10 FSI biturbo

Technical features

– Ten-cylinder petrol engine with aluminium block

– Cylinder head with dual overhead camshafts
(DOHC)
– Roller cam followers with hydraulic valve
clearance adjustment
– Variable intake and exhaust camshaft
adjustment
– Maintenance-free, chain-driven timing gear
– Demand-controlled low and high pressure fuel
system
– Homogeneous direct injection

431_009

500 1000
Torque/power curve

400 800
Max. torque in Nm

300 600
Max. power in kW
kW Nm

200 400

100 200

0
0 1000 2000 3000 4000 5000 6000 7000 8000
Engine speed in rpm

Specifications of the Audi RS 6

Engine code BUH

Engine type Ten-cylinder petrol engine with petrol direct injection,
biturbo charging and closed-loop fuel system

Displacement in cm3 4991

Max. power in kW (bhp) 426 (580) at 6250 – 6700 rpm
Max. torque in Nm 650 at 1500 – 6250 rpm
Bore in mm 84.5
Stroke in mm 89
Compression ratio 10.5 : 1
Cylinder spacing in mm 90
Firing order 1 - 6 - 5 - 10 - 2 - 7 - 3 - 8 - 4 - 9
Engine management Bosch ME9.1.2
Exhaust emission control Single-pipe manifold with 4 integrated main catalytic converters close
to the engine, each with 1 pre-catalyst sensor and 1 post-catalyst sensor

Exhaust emission standard EU 4

8
 Differences with regard to engine components of 5.2l V10 FSI engine (SSP 376)

– No balancer shaft
– Change in displacement due to modified crankshaft with shorter stroke
– Crankshaft with continuous crank pin
– Dry sump lubrication system
– Oil and water pump module
– Modified crankcase ventilation system with heating
– Exhaust manifold turbocharger module

Crankcase ventilation system

with fine oil separator
on right cylinder bank

Intake manifold without

switching flaps,
with throttle valve parts

Exhaust manifold
turbocharger module,
left cylinder bank

Exhaust manifold
turbocharger module,
right cylinder bank

Intake module (baffle plate)

431_041

Oil and water pump module

9
 Engine mechanicals

Cylinder block/crank
mechanism

The cylinder crankcase with 90° v-angle uses a Cylinder crankcase

bedplate design and, thanks to a length of 685 mm
and width of 80 mm, sets new standards for com-
pactness and overall length.

The top part of the cylinder crankcase is a homo-

geneous monoblock made from AlSi17Cu4Mg by
low-pressure chill casting.
The typical properties of this combination of
materials are high strength, very low cylinder
distortion and good heat dissipation.

Ladder frame (bedplate)

The AlSi12Cu1 bedplate has been reinforced by

using cast-in GGG50 inserts attached with four
screws through which the bulk of the power flow
is directed.
These inserts also reduce thermal expansion and
play in the main crankshaft bearings at high
temperatures.

431_046
Cast iron insert for
crankshaft main bearing

Instead of an oil pan, the engine has an intake This intake module does not have a large oil
module which is connected directly to the external reservoir, rather serves as a baffle plate and collects
oil pump via intake ports. the out-flowing oil due to the rotation of the crank-
shaft.

Intake module (baffle plate) Baffle plate

Coolant intake for

right cylinder bank

Intake ports
431_074

Hydraulic oil port for

engine lubrication

10
Crankshaft

For strength reasons, the crankshaft has been

designed as common-pin-type crank pin, and not
a split-pin type like on the 5.2l V10 engine.

compared to split pin

Crankshaft with common pin on 5.2l V10 engine
on 5.0l V10 engine

431_066

431_044

Chain drive
Chain drive is provided by four 3/8" roller chains Chain drive D acts as an ancillary unit drive, and
working on two planes. drives the oil and water pump module, the air con-
Chain drive A acts as a distributor drive inter- ditioning compressor and the power steering pump.
connecting the crankshaft and the idler gears. Four hydraulic tensioners with non-return valves are
Chain drives B and C act as cylinder head drives used as a tensioning system.
interconnecting the idler gears and each of the Like the chains, they are designed for lifetime use.
camshafts.

Hydraulic tensioner
Hydraulic tensioner for chain drive C
for chain drive B
Idler gear

Deflection sprocket
Hydraulic tensioner
for chain drive A
Auxiliary drive for:
- Oil and water pump module Hydraulic tensioner
- Air conditioning compressor for chain drive D
- Hydraulic pump for power steering 431_042
3/8" simplex roller chain
for all chain drives

11
 Engine mechanicals

Oil circulation system

Oil tank with integrated

crankcase breather

Oil filter module

Radiator/oil cooler
Baffle plate

Oil return line from cylinder

head, right cylinder bank

Turbocharger
return oil extractor

Cooling air flow

Oil return line from
cylinder head,
left cylinder bank

431_020
Oil and water pump
Direction module
of travel
Auxiliary oil cooler
(air/oil)

A dry sump lubrication system is used to ensure a The oil is again extracted from the oil reservoir and
reliable supply of pressurised oil to the engine in pumped under pressure into the engine oil circuit
all driving situations and when cornering at high by the oil pump module.
speeds. Depending on the position of the oil thermostat, the
Since the engine has an intake module, and not an oil is pumped to the oil cooler either directly or via
oil pan, the recirculated oil must be extracted from the auxiliary oil cooler (air/oil).
the bearings, the cylinder heads and the chain
housing by means of suction.
The extracted oil is pumped into the oil reservoir via
an oil thermostat by the oil pump module.

12
Oil reservoir
Primary oil separator for
crankcase ventilation

Dip stick

Crankcase breather of
left cylinder bank and
inner-v of engine

to fine oil separator

Cover and housing seal

Oil filler tube Cyclone

Defoaming
Oil level/oil temperature and settling chamber
sender G266

Baffle plates

Oil collecting chamber

431_021

Oil collecting
chamber

Extraction system

to oil pump
from oil thermostat

The oil which is pumped into the oil reservoir by When the oil flows out of the oil reservoir, it passes
the oil pump module flows into a dual-flow oil pipe through baffle plates, where it is defoamed and
which leads to a cyclone. When the oil is admitted allowed to settle. The rising blow-by gases flow into
into the cyclone, it is set into rotation and the oil separator at the top of the oil reservoir.
simultaneously degassed. The oil filler tube, the dip stick and the oil level and
oil temperature senders G266 are integrated in the
oil reservoir.

13
 Engine mechanicals

Oil pump

The oil pump module is external to the engine and The oil pump and the coolant pump collectively
driven via chain drive D. It consists of the suction form a unit and can only be replaced as such.
and feed pump for filling the oil reservoir, the suc- Only the thermostat housing with integrated
tion and pressure pump for supplying oil to the coolant thermostat can be replaced separately.
engine, and the suction pump for the recirculating
turbocharger oil.

Suction pump for the

turbocharger oil return line Coolant intake port,
left cylinder bank
Oil pump module driven
Thermostat housing
by chain drive D Oil pumps

431_024

Coolant pump

Connection of the oil pump

module to the intake module

Hydraulic oil port leading Coolant intake port,

into engine oil circuit right cylinder bank

14
Oil flow

In the suction pump, the oil returning from the In the pressure pump, the cooled oil is extracted
lubrication points is drawn off as it passes through from the oil reservoir and pumped into the engine
the suction module and pumped into the oil oil circuit.
reservoir.

431_025

Legend:

1 Crankshaft chamber 5 (K5) 9 to oil thermostat

2 Chain case return line 10 to main oil port

3 Oil return line from cylinder head, 11 from oil reservoir

right cylinder bank
12 Suction pump
4 Oil return flow from cylinder head,
left cylinder bank 13 Pressure pump

5 Crankshaft chamber 4 (K4) 14 Suction pump for oil return from

both turbochargers
6 Crankshaft chamber 3 (K3)
15 Crankcase divider
7 Crankshaft chamber 2 (K2)

8 Crankshaft chamber 1 (K1)

Oil pressure at idle min. 1.5 bar; at 2000 rpm min 3.5 bar.

15
 Engine mechanicals

Oil thermostat

To ensure better cooling, an auxiliary oil cooler is The auxiliary oil cooler is controlled by an oil
integrated in the oil circulation system. Oil either thermostat installed on the underside of the engine.
flows through it or bypasses the auxiliary oil cooler,
depending on its temperature.

Thermostat closed

Resetting spring (relaxed)

Expansion element
thermostat

from the oil pump

Oil pump module

431_035

Oil cooler

Oil tank

Direction of travel

When the engine is cold or the engine lubricating In combination with the heat exchanger (oil/water)
oil is cold, the recirculating, extracted oil is pumped in the inner-v of the engine, the engine lubricating
into the oil thermostat housing. oil is heated to operating temperature more quickly.
When the thermostat is in a relaxed state, it seals
off the inlet leading to the oil cooler, whereby the oil
in the thermostat housing is redirected to the oil
reservoir.

16
Thermostat open

Resetting spring (tensioned)

Expansion
type
thermostat

Annular port

Oil pump module

431_037

Oil cooler

Oil tank

Direction of travel

When the temperature of the oil exceeds 100 °C, The oil flows through this annular port and into the
the oil thermostat opens the inlet to the oil cooler. oil cooler, returning from here to the oil thermostat
An expanding element in the thermostat expands housing and entering the oil reservoir.
under heating and exerts pressure against the In the oil cooler, the engine lubricating oil is cooled
thermostat housing. Due to the pressure of the by the air stream generated by the vehicle as it
expanding element, the thermostat is displaced moves.
against the force of the spring, opening the annular
channel and simultaneously closing off the inlet
leading directly to the oil reservoir.

17
 Engine mechanicals

Crankcase ventilation

The blow-by gases produced by combustion are extracted from the left rocker cover in the inner-v of the
engine and routed to the primary oil separator of the crankcase breather, which is mounted on the oil
reservoir.

Primary oil separator

Pressure regulating valve

for crankcase ventilation

Cyclone Fine oil separator on

right cylinder head
Labyrinth

Oil level and

oil temperature sender
G266

Oil reservoir with

oil separator

Turbocharger, right

After the blow-by gases have been admitted into the The blow-by gases from the right cylinder bank are
primary oil separator, they pass through a labyrinth also admitted into this fine oil separator, after which
and then through ten cyclones where the coarse oil they are directed into the combustion chamber
droplets are separated from the blow-by gases. together with the other blow-by gases.
The gases then flow into the fine oil separator on Since both vacuum and charging pressure (over-
the right rocker cover. pressure) are alternately present inside the intake
manifold in turbocharged engines, the oil-free blow-
by gases must flow into the combustion chamber
through different ports.

18
 To prevent the admitted blow-by gases from freezing at high flow rates, the inlet port on the intake manifold
is heated with coolant from the cylinder heads.

Heating of the
crankcase
breather at the
rear intake Outflow and
manifold distribution of
blow-by gases to
Coolant return to both cylinder banks in
expansion tank the intake manifold

Coolant port leading

Vacuum port leading
from left cylinder head
to brake servo

Coolant port leading

from left cylinder head
Admission of oil-free
blow-by gases downstream
of the fine oil separator

Non-return valve in the intake line leading to

the turbocharger (open when vacuum is present
in the intake line upstream of the turbocharger)

Intake
manifold inlet
Port leading from
inner-v of engine Port leading to left cylinder head
block

Non-return valve on intake

manifold (open when vacuum is
present in the intake manifold)

Admission of blow-by gases when charge

pressure is present in the intake manifold
located upstream of the turbocharger
turbine.

431_065

Left turbocharger

When the engine is idling and running at par t When the engine is running at full throttle and
throttle, a non-return valve on the intake manifold is charge pressure is present in the intake manifold,
opened by vacuum, allowing the blow-by gases to the non-return valve on the intake manifold is
be drawn in. At the same time, the two non-return closed and the non-return valves on the intake end
valves on the turbochargers are closed. of the turbocharger are opened. The oil-free blow-by
gases now flow into the pressureless section of the
turbocharger and are directed to the combustion
chamber via the charge air line leading to the intake
manifold.

19
 Engine mechanicals

Cooling system

Secondary cooling circuit (engine cold) Main radiator

Auxiliary radiator, left

Coolant thermostat

Coolant pump

Direction
Water oil pump module of travel Auxiliary radiator,
driven by chain drive D bottom front

When the coolant thermostat is closed, the supply from the inner-v of the engine to the coolant pump is
opened internally.
Coolant flows directly to the coolant pump and back into the engine cooling system.
This is the secondary cooling circuit, in which components such as the engine oil cooler (water/oil), the alter-
nator, the turbocharger and the heating system heat exchanger are integrated.

to
engine

to
engine

431_053
from
engine

Coolant thermostat
closed
Coolant thermostat
opened internally

20
 Level gauge on right A-post,
visible when door is open

Filler tank

Expansion tank

Port leading
from filler tank

Auxiliary radiator, right

Auxiliary coolant regulator

for right auxiliary radiator 431_073

Port leading to heating

return line serving as a
filler line for the coolant
system.

Auxiliary coolant regulator for right auxiliary

radiator

When it is in a cold state, the auxiliary coolant

regulator for the right auxiliary radiator is closed.
Coolant flows from A to C to the main radiator,
bypassing the auxiliary radiator.

Legend:

A Coolant flows from oil the cooler (water/oil)

in the inner-v of the engine

B closed

C Coolant bypasses the auxiliary radiator

(short-circuit line)

431_055

21
 Engine mechanicals

Primary cooling circuit (engine warm) Port leading to heater heat exchangers
via pump/valve unit in plenum chamber

Connection for gearbox

oil cooling supply line

Connection for
heater return line

Connection for gearbox

oil cooling return line

When the coolant thermostat is open (at a temperature of 87 °C or higher), the inlet from the inner-v of the
engine to the coolant pump is closed internally.
Coolant passes through the main radiator and, after cooling down, flows to the coolant pump.
The coolant from the inner-v of the engine is now directed via a branch line to the left auxiliary radiator.
This means that the auxiliary radiator is thermostat-controlled both on this side and on the right-hand side.
The main radiator and the left auxiliary radiator are integrated in the primary cooling circuit at the centre and
on the right, creating a large cooling surface which serves to regulate the coolant temperature.

to
engine
left cylinder bank

to from
engine heater
right cylinder bank

from
radiator

431_058

Coolant thermostat
activated

Coolant thermostat
internally closed
from
gearbox cooler

22
 Level gauge on right A-post
visible when door is open

Port leading from filler tank

to expansion tank

431_031

Auxiliary coolant regulator for right auxiliary

radiator

When the coolant temperature exceeds 90 °C, the

auxiliary coolant regulator opens, allowing coolant
to flow unrestricted from A to B.
The coolant now passes through the right auxiliary
radiator and into the main radiator.

Legend:

A Coolant flows from oil the cooler (water/oil)

in the inner-v of the engine

B Coolant flows into the auxiliary radiator via

the coolant thermostat

C closed

412_054

23
 Engine mechanicals

Cooling circuit diagram

(engine at operating temperature)
10
9
The direction of flow arrows represent
8 the engine at operating temperature.
11

12 13 14

7
6

16

5
17

3 19

18
15 20
2

21

431_061
1 26 25 24 23 22

Legend:

1 Right auxiliary radiator 14 Left exhaust gas turbocharger

2 Auxiliary coolant regulator 15 Coolant pump

3 Filler tank 16 Auxiliary coolant regulator for gearbox oil

cooling
4 Alternator
17 Oil cooler for transfer case (water/oil)
5 Coolant run-on pump V51
18 Coolant thermostat
6 Coolant expansion tank
19 ATF cooler (water/oil)
7 Right exhaust gas turbocharger
20 Recirculation pump 2, V403
8 Pump/valve unit
21 Non-return valve
9 Right heater heat exchanger
22 Left auxiliary radiator
10 Left heater heat exchanger
23 Main radiator
11 Vent screw
24 Gearbox radiator (water/air)
12 Crankcase breather heater on intake manifold
25 Bottom auxiliary radiator
13 Top engine oil cooler (water/oil)
26 Coolant temperature sender G62

24
Diagram showing the cooling system
in run-on mode

431_076

To protect the turbocharger from damage due to This circulation process dissipates the collected
heat build-up after shutting off the hot engine, the heat from the turbochargers by utilising the large
engine control unit J623 (master) activates the surface area of the radiator and the radiator fan run-
timer-controlled run-on pump V51 via the auxiliary on function.
water pump relay J151. If this does not happen, the hot oil can coke up in
the turbocharger bearings and damage the floating
Depending on the coolant temperature, the pump bearings of the turbine shaft.
runs for 540 seconds and runs on for up to 800
seconds.
The run-on pump (reversing the normal direction
of coolant flow) feeds the coolant from the main
radiator via the turbocharger into the engine block,
and then recirculates it through the main radiator
via the open coolant thermostat.

25
 Engine management

System overview
Sensors

Intake manifold pressure sender G71

Intake manifold temperature sender G72

Accelerator pedal position sender G79

Accelerator pedal position sender 2, G185

CAN data bus

Engine speed sender G28 Drive

Knock sensors 1+2, G61, G66

Fuel pressure sender G247

Hall sender G40

Hall sender 3, G300

Throttle valve module J338

Throttle valve drive angle sender 1+2
(electric power control) G187, G188

Coolant temperature sender G62

Engine control unit J623
(master)

Charge pressure sender G31

Fuel pressure sender, low pressure G410

Intake manifold flap potentiometer G336

Lambda probe G39

Lambda probe after catalytic converter G130

Brake light switch F

Brake pedal switch F47

Auxiliary signals:
Cruise control system on/off
Terminal 50
Wake up door contact from convenience system
central control unit J393

Charge pressure sender 2, G447

Engine control unit 2, J624

(slave)

Fuel pressure sender 2, G624

Hall sender 2, G163

Hall sender 4, G301

Throttle valve module 2, J544

Angle senders 1+2 for throttle valve
drive 2, G297, G298

Knock sensors 3+4, G198, G199

Oxygen sensor 2, G108

Oxygen sensor 2 after catalytic converter G131

Intake manifold flap 2 potentiometer, G512

26
 Actuators
Fuel pump control unit J538
Fuel pump (pre-supply pump) G6

Ignition coils N70, N127, N291, N292, N323

Cylinders 1 – 5

Fuel metering valve N290

Activated charcoal filter solenoid valve 1 N80

Electro/hydraulic engine mounting solenoid valve,

right N145

Starter motor relay J53

Starter motor relay 2 J695

Fuel system diagnostic pump (USA) V144

Intake manifold flap valve N316

Charge pressure control solenoid valve 1+2, N75, N274

Injectors, cylinders 1 – 5
N30 – N33, N83

Inlet camshaft timing adjustment valve -1- N205

Exhaust camshaft timing adjustment valve 1 N318

Throttle-valve drive for electric power control G186

Continued coolant circulation relay J151

Coolant run-on pump V51

Lambda probe 1 heater, Z19

Lambda probe 1 heating, after catalytic converter Z29

Variable intake manifold change-over valve N335

Diagnostic
port Secondary air pump relay J299
Secondary air pump motor V101
Secondary air inlet valve N112

Auxiliary coolant pump relay J496

Recirculation pump 2, V403 (gearbox oil cooling)

Engine component current supply relay J757

Motronic current supply relay J271

Auxiliary signals:
Engine speed
Radiator fan control units J293 and J671

Ignition coils N324 – N328

Cylinders 6 – 10

Inlet camshaft timing adjustment valve 2 N208

Exhaust camshaft timing adjustment valve 2 N319

Injectors, cylinders 6 – 10
N84 – N86, N299, N300

Lambda probe 2 heater, Z28

Lambda probe 2 heater, after catalytic converter Z30

Fuel metering valve 2 N402

Electro/hydraulic engine mounting solenoid valve,

left N144

Throttle valve drive 2, G296

Radiator fan 3 relay, J752

431_064 Radiator fans, left and right V402, V35

27
 Engine management

Engine management

The engine management system utilises a p/n Correction factors are:

control system without an air mass meter.
– cylinder-selective knock control
The intake manifold pressure sender G71 and the – lambda control
intake manifold temperature sender G72 are – idle speed control
mounted on the intake manifold at the front and – activated charcoal filter control
directly in contact with the intake air inside the
intake manifold. Substitute function

The engine control unit J623 (master) utilises the If no signals are received from the intake manifold
following variables to compute the engine load: pressure sender, the engine control unit utilises the
signal from the throttle valve potentiometer and
– Engine speed (n) the engine speed signal to calculate the injection
– Intake manifold pressure (p) duration and timing. If no signal is received from
– Intake manifold temperature the intake air temperature sender, a substitute value
– Throttle valve angle of 45 °C is used.

The control unit calculates the injection timing

and duration, and takes into account the relevant
correction factors.

Charge pressure sender G31 Charge pressure sender 2, G447

431_090

Intake manifold pressure sender G71

Intake manifold temperature sender G72

28
Charge pressure control

Each cylinder bank has its own turbocharger circuit A control pressure is generated from the charge
and consists of the following components: pressure and the intake pressure via the cyclically
operated charge pressure control solenoid valves
– Exhaust manifold turbocharger module N75/N274.
– Charge-air cooler (air/air)
– Charge pressure control solenoid valve/ The applied control pressure acts on the vacuum
wastegate operation actuators, which in turn actuate the wastegate flaps
– Charge pressure sensor via linkages. Each of the wastegate flaps opens a
– Throttle valve part bypass allowing the exhaust gases to partially by-
pass the turbines and flow into the exhaust system.
A charge pressure sensor is integrated in each The charge pressure control system can be used to
charge air line leading from the charge-air cooler regulate the rotational speed of the turbines and
to the intake manifold. thereby set the maximum charge pressure.
The engine control unit compares the signal from
the charge pressure sensors with the characteristic When the engine running in overrun mode, the
map, and sends the signal via the charge pressure charge pressure control solenoid valves N75/N274
control solenoid valves N75/N274 to the vacuum open the bypass leading from the charge air
actuators of the turbochargers. turbines to the intake manifold upstream of the
turbochargers and thereby control the wastegate.

Wastegate flap

Vacuum actuator
with linkage
Exhaust manifold

431_072

Charge pressure (control pressure)

from the turbine

Wastegate flap activation

Wastegate control
Charge pressure control
solenoid valve N75

Note

When the charge pressure control system is

deenergised, the charge pressure acts directly
upon the vacuum actuator and against the force
of the vacuum actuator spring. The maximum
possible charge pressure is thus limited to the
basic boost pressure level.

29
 Engine management

Turbocharger oil extraction system

Extraction pump

Turbocharger, left

431_039

Turbocharger oil extraction Turbocharger oil extraction

system, left-hand side system, right-hand side

Oil line leading to oil reservoir

via oil thermostat

The turbochargers are supplied with oil from the oil The suction pump is integrated directly in the oil
pressure ports on the cylinder heads. The return oil pump module and pumps the extracted oil inter-
does not return to the engine block as before, but is nally into the oil reservoir via the feed pump and the
drawn off by a separate extraction pump. oil thermostat.

Oil feed pipe from Air pipe connection for

cylinder head filtered air from the air filter

Flow control

At high engine speeds, the high suction capacity of

the extraction pump is reduced by means of the
intake air.

The suction pump creates a so-called Venturi effect

at the connection between the oil return pipe and
the air pipe, whereby air is drawn out of the air filter
and into the oil extraction flow.
This air/oil mixture is fed internally into the oil
reservoir by the feed pump, the elements again
being separated inside the oil reservoir cyclone.

The extraction pump has a high suction capacity

due to the high engine speeds. Without volumetric
flow control, the oil could be drawn off before
reaching the lubrication point in the turbocharger.

431_071
Oil return pipe
Connection between
oil return pipe and air pipe

30
 Automatic gearbox 09E

Automatic gearbox 09E

Independent oil supply
The six-speed automatic gearbox 09E known from
the Audi A8 is used on the Audi RS 6.

In combination with the V10 biturbo engine, the

following special features are worth mentioning in
addition to the adjustments that have been made
with regard to torque and engine speed:

– Gearbox oil cooling for transfer case and front

axle cooling (common oil supply) 431_091
– Thermostat-controlled gearbox oil cooling with
electric recirculation pump 2, V403 Common oil supply
– Self-locking centre differential (40/60)
– Mechatronics with shorter operating times

The hydraulic control system (mechatronics and

gearbox hardware) have been adopted from the
0B6 gearbox (Audi A4 2008).

431_092

Reference
For more detailed information about the
ATF oil circulation system new mechatronics module, please refer to
Gearbox oil circulation system SSP 385 "Six-speed Automatic Gearbox".

Supply line Protective tube

431_093

Oil pump for

transfer case Return line Heat exchanger
Heat exchanger for for ATF cooling
gearbox oil cooling

The oil pump for the transfer case pumps gearbox

oil through the heat exchanger for gearbox oil
cooling (oil/water) via the lines connected to the
exterior of the gearbox.

Since the double oil seal ring is not installed in the Note
protective tube on this version of the 09E gearbox, Please follow the instructions for checking
gear oil from the front axle drive can enter the the oil levels and for refilling the gearbox
transfer case through the protective tube. oil after repair work in the current service
This ensures that the oil from the front axle drive is literature ("Transfer case and final drive
cooled. The 09E gearbox with common oil supply is with common oil supply").
already used in the twelve-cylinder Audi A8.

31
 Automatic gearbox 09E

Gearbox oil cooling

Coolant for gearbox oil cooling is extracted from the main radiator at the top left and pumped into the
gearbox oil cooling circuit by a separate auxiliary water pump.

The automatic transmission fluid and the transfer case oil are cooled by separate heat exchangers (water/oil)
using coolant.

Gearbox radiator

Heat exchanger
for transfer case
Main radiator
connection

ATF heat exchanger

for gearbox

431_034

Coolant thermostat
Main radiator

Thermostat housing
of coolant pump

Auxiliary water pump for gearbox

oil cooling (recirculation pump 2, V403)
The coolant thermostat must face towards
the thermostat housing of the coolant pump,
as indicated by the arrow.

32
 cold - closed

Themostat control

An additional "coolant thermostat" integrated in the

gearbox oil cooling system opens only when the
temperature of the coolant exceeds 87 °C, thereby
enabling the automatic gearbox to reach its
operating temperature quickly and ensuring that
the gearbox is provided with sufficient cooling
under load at temperatures of 87 °C and higher. 431_068

warm - open

431_069

Activation of recirculation pump 2, V403

The following components are involved in the

activation of the gearbox oil cooling system:

– Motronic current supply relay J271

– Engine control unit 2, J624 (slave)
– Auxiliary coolant pump relay J496
– Recirculation pump 2, V403

Motronic current supply relay J271 supplies relay

J496 with voltage at terminals "30" and "86".
Engine control unit 2, J624 (Slave) applies an earth
signal to terminal "85" of the auxiliary coolant pump
relay J496 when a coolant temperature of 90 °C is
reached.
When relay J496 closes, it supplies recirculation
pump 2, V403 with voltage via terminal "87A". Once
energised, the recirculation pump runs until the
engine comes to a halt.

431_096

33
 Suspension system

Dynamic Ride Control – DRC

DRC sports suspension systems

The Audi RS 6 is fitted as standard with a sports The task of the system is to reduce body roll and
suspension featuring Dynamic Ride Control (DRC). pitch, which typically occur under acceleration/
The sports suspension plus package is optional. braking and when cornering.

The DRC system is a purely mechanical system, in The DRC system works on a two-phase principle: 1.,
which the shock absorbers are interconnected hy- a uniform phase and 2., a counter-phase.
draulically by means of central valves in a diagonal
configuration. To accomplish this, the front left
shock absorber is connected to the rear right shock
absorber and the front right shock absorber to the Reference
rear left shock absorber via a central valve with a Please refer to the Computer Based
pressure-equalising chamber. Training (CBT) relating to the
Audi RS 4.

Shock Shock
Uniform phase absorber, absorber,
front left rear right
Pressure
The uniform phase occurs when the entire sus- equalising chamber
pension system "bumps", for example when driving
over an uneven section of motorway.

Both the shock absorbers on each axle compress

simultaneously. The increase in pressure due to the
piston rods moving downwards compresses the gas
in the pressure equalising chamber of the central
valve.

DRC line

431_077

Shock Shock
Counter-phase absorber, absorber,
front left rear right
The counter-phase takes place during roll and
pitch movements of the vehicle, for example when
cornering. When negotiating a right-hand curve, the
front left shock absorber bumps and the rear right
shock absorber rebounds.
The DRC system counteracts this physical principle.

Different damper movements produce different

pressure potentials in the central valve.
Both pressure potentials present at the central
valve are equal and act in precisely the opposite
directions. The forces therefore cancel each other
out, as a result of which no shock absorber move-
ment takes place and body roll is suppressed.

Central valve 431_078

34
Sports suspension plus with DRC

The optional sports suspension plus is based on the From a technical point of view, the adjuster units on
DRC suspension, but additionally features a three- the shock absorbers of the sports suspension plus
stage adjustable shock absorber rate. represent bypasses with a variable through-flow
The three shock-absorber firmness settings – cross-section.
"comfort", "dynamic", "sport" – can be selected by
the driver via the MMI. In the shock absorber setting "sport", the rotation
valve is activated in such a way that the upper
These adjustments are possible due to adjuster channel (6) is closed. As a result, no damping fluid
units with servomotors on the shock absorbers. is able to flow through the adjusting element.
The adjuster unit is fitted directly to the shock The piston in the adjusting element is thereby
absorber. It consists of a DC motor, which actuates disconnected from the hydraulic circuit. The entire
a roller-shaped rotation valve, and a Hall sensor, damping fluid must pass only the piston in the
which signals the adjustment of the motor to shock absorber. The "sport" setting represents the
the ECD control unit (electronically controlled firmest damper setting.
damping) J250.

Hydraulic circuit of a shock absorber of the sports

suspension plus:

1 Direction of piston movement

2 Lower port

3 Lower channel

4 Piston in the adjuster unit

5 Rotation valve

6 Upper channel

7 Channel between inner and outer tubes

Oilway
Additional
8 Upper port element

Piston in shock
absorber

Servomotor

431_079

35
 Suspension system

In the damper setting "dynamic", the rotation valve In the "comfort" damper setting, the rotation valve
is activated in such a way that the bypass is "half- is activated to the extent that the bypass is "fully
open". open". Even more damping fluid can now flow
The damping fluid can now flow through the piston through the piston of the adjusting element.
of the adjusting element and through the piston in This allows the most comfortable shock absorber
the shock absorber. A softer shock absorber rate is set-up to be realised.
thereby achieved.
The "dynamic" setting, the firmness of the shock
absorbers roughly corresponds to the shock
absorber rate of a standard DRC sports suspension.

Networking of sports suspension plus with DRC Diagnostic port

MOST ring

Diagnostics
CAN bus

ECD Control Module Powertrain CAN bus Data bus

(electronically controlled damping) diagnostic interface
J250 J533

Dash panel insert CAN bus

PWM Front information
control unit
J523

431_080

Shock absorber Shock absorber Shock absorber Shock absorber Control unit with
electronics, electronics, electronics, electronics, display control unit
front left front right rear left rear right J285
N336 N337 N338 N339

The shock absorber adjusting elements, wheel The ECD control unit (electronically controlled
electronics N336 to N339, are activated by the damping) J250 on the Audi RS 6 is similar to the
ECD control unit (electronically controlled damping) adaptive suspension control unit J197 on the
J250. Audi A6 allroad and is also installed in the same
The Hall sensors of the shock absorber damping position - behind the glove box.
electronics signal the position of the servomotors
to control unit J250 by means of pulse width modu- The ECD control unit (electronically controlled
lated signals. damping) J250 is connected to the data bus diag-
nostic interface J533 via the powertrain CAN data
bus. The driver can set the desired shock absorber
rate using the MMI.

36
Warning lamp for sports suspension plus
Warning lamp for sports
suspension plus in dash
When the ignition is turned on, the yellow warning panel insert
lamp of sports suspension plus lights up briefly.

When an electrical malfunction occurs in sports

suspension plus, the warning lamp lights up
continuously.
On the MMI panel, all three shock absorber rates are
greyed out so that the driver can no longer adjust
the shock absorber rate.

431_081

Special tools and workshop equipment for

the DRC system

The VAS 6209 filling system known from the Filling system for DRC central valves VAS 6209/3
Audi RS 4 can be used to fill and evacuate the
DRC hydraulic system.
The procedure for filling and evacuating hydraulic
lines between the central valve and the shock
absorbers is, in principle, identical to the procedure
for the Audi RS 4, model B7.
When repair work is needed, please follow closely
the description given in the Workshop Manual of
the RS 6.

A new item is the filling system for DRC central

valves VAS 6209/3.
Pressureless, undamaged DRC central valves, for
example valves which have become pressureless
due to a leaking shock absorber, can be refilled
using the filling system for DRC central valves 431_082
VAS 6209/3.
The hand pump integrated in the system allows
pressures of over 20 bar to be built up, thereby
enabling the pressure equalising chamber in the
DRC central valve to be compressed again.

Note

DRC hydraulic lines on the sports

suspension plus may only be evacuated
and filled in the "comfort" shock absorber
setting.

37
 Suspension system

Wheels and tyres

Standard equipment Optional equipment Optional equipment

Cast aluminium wheel Cast aluminium wheel (silver or titanium finish) Cast aluminium wheel
10-spoke design 9J x 19 Five-segment spoke design 9.5J x 20 Seven double spoke design
suitable for snow chains unsuitable for snow chains 9.5J x 20
unsuitable for snow chains
Tyres: 255/40 R 19 Tyres: 275/35 R 20
also available as winter tyre also available as winter tyre Tyres: 275/35 R 20
also available as winter tyre
Cast aluminium wheel
Five-segment spoke design 9J x 20
suitable for snow chains

Winter tyres: 265/35 R 20

Brake system
Fixed caliper of the steel brake
The Audi RS 6 is fitted standard with a 19‘‘ steel
(front axle)
brake system and optionally with a 20‘‘ ceramic
brake system.
Unlike on the Audi RS 4, the optional ceramic brake
system on the Audi RS 6 has ceramic brake discs at
the front and rear.

Steel brake

– PR number 1LM (front wheel brake) and 1KJ

(rear axle brake) Centre guide bolt
– Front brake disc: 390 x 36 mm, drilled, ventilated
– Front brake caliper: Brembo 6-piston caliper
(painted black with "RS" logo)
– Rear brake disc: 356 x 28 mm, drilled, ventilated
– Rear brake caliper: TRW single-piston caliper
with electromechanical parking brake
(painted black)

The steel brake discs on the Audi RS 6 are not uni-

directional. When changing the front brake linings,
particular attention must be paid to correct fitting
of the centre guide bolt.
431_087

38
Ceramic brake Fixed caliper of the ceramic brake
(front axle)
– PR number 1LN (front wheel brake) and 1KK
(rear wheel brake)
– Front brake disc: 420 x 40 mm, drilled, ventilated
– Front brake caliper: Alcon 8-piston caliper
(painted anthracite with "Audi ceramic" logo)
– Rear brake disc: 356 x 28 mm, drilled, ventilated
– Rear brake caliper: TRW single-piston caliper
with electromechanical parking brake
(painted anthracite)

The brake discs of the ceramic brake are

unidirectional, both on the front and rear axles.

The rear-axle brake calipers are identical in the steel

brake and ceramic brake versions, except that the
brake calipers are painted in different colours.
Please note that the steel and ceramic rear-wheel
brakes have different brake pads.

431_088

Designation of the ceramic brake disc on the brake

disc bowl: Ceramic brake discs of the rear axle

1 Direction of travel
2 Audi logo
3 Supplier
4 Serial production number
5 Audi part number
6 Audi rings
7 Production date
8 Permissible minimum thickness of the
brake disc
9 Weight of the new brake disc including
brake disc bowl

The ceramic brake discs are made of carbon

reinforced silicon carbide (C/SiC).
Although this material has little in common with
household ceramics, special care is required when
handling these brake discs.

Unlike steel brake discs, where wear is indicated

by material abrasion only, ceramic brake discs are
431_089
subject to both mechanical and thermo-chemical
wear.
Thermo-chemical wear is where atomic carbon is
emitted from the carbon reinforced silicon carbide.
Reference
This can be determined either by visual inspection
or by weighing the brake discs. For information about the handling and
assessment of wear and damage in
ceramic brake discs, please refer to the
current service literature.

39
 Electrical system

Bus topology Lane change assist

Multifunction Multifunction
Adaptive cruise
steering wheel
steering wheel
control unit -2- Lane departure control unit
Lane change assist warning system
J770** J428
J769** J759

Control unit
with display
control unit
J285

Diagnostic port
T16

Data bus
diagnostic interface
J533

Door control unit, Energy management

Engine control unit 2 Engine control unit driver side control unit
J624 J623 J386 J644

Door control unit, Rear-view camera

Yaw rate sender ABS control unit front pass. side system control unit
G202 J104 J387 J772

Seat occupied
Door control unit, Parking aid
recognition Airbag control unit rear left control unit
control unit J234 J388 J446
J706*

Automatic gearbox Door control unit, Onboard power

control unit rear right supply control unit 2
J217 J389 J520

Power output module

for left headlight
J667
Seat and steering Entry and start
Headlight range column adjustment authorisation
control, control unit control unit with control unit
J431 memory J518
Power output module J136
for right headlight
J668

Seat adjustment control Onboard power supply

Electric park and unit with memory,
handbrake control unit control unit
front passenger
J540 J519
J521

ECD Control Module Convenience system

(electronically Tailgate control unit central control unit
controlled damping) J605 J393
J250

Steering column Climatronic

Steering angle sender electronics control unit
G85 control unit J255
J527

Multifunction steering Tyre pressure monitor

wheel control unit control unit
J453 J502

40
 Telephone
transmitter and
receiver unit
R36

External audio device

Front information connection
control unit R199
J523

Navigation system
with CD drive
control unit
J401

TV tuner
R78

CD changer
R41 Digital radio
R147

Digital sound package Voice input

Radio control unit
control unit
R J507
J525

MOST bus

Dash panel insert CAN bus

Diagnostics CAN bus

Reversing Aerial reader unit
Entry and start for entry authorisation
authorisation switch for keyless entry system Powertrain CAN bus
E415 J723

Convenience CAN bus

CAN Extended
Wiper motor Rain and light
control unit detector sensor
J400 G397 LIN bus

Miscellaneous subbus systems

Interior monitoring
Alarm horn
sensor * USA only
H12
G273

** to be launched at a later date

Fresh air blower Refrigerant pressure/

control unit temperature sender
J126 G395

Tyre pressure monitor Tyre pressure monitor Tyre pressure monitor Tyre pressure monitor 431_095
Rear tyre pressure
sender unit in front left sender unit in front right sender unit in rear left sender unit in rear right
monitor aerial
wheel housing wheel housing wheel housing wheel housing
R96
G431 G432 G433 G434

41
 Electrical system

Headlights

The Audi RS 6 is equipped with bi-xenon headlights Unlike on the Audi S6, the ten LEDs for the daytime
and adaptive light. The fog lights are integrated in running lights and position lights are also integrated
the headlights. in the headlights.

Fog light Dipped-beam headlights and main-beam Turn signals

headlights (gas discharge lamp, bi-xenon)

431_094

Daytime running lights and position lights,

dimmed (ten LEDs)

Bulbs Type Power output

Daytime running lights and position LED 10 watts

lights

Dipped-beam headlights and main- Gas discharge lamp D2S 35 watts

beam headlights

Turn signals PY21W (silver glass) 21 watts

Fog light H7 55 watts

The rear lights of the Audi RS 6 are identical to those of the Audi A6 in the Highline trim version.

42
The 10 LEDs are operated as daytime driving lights or, in the dimmed version, as position lights.

The LED units are activated by the onboard power supply control unit J519. If the onboard power supply
control unit sends a 12V signal to the LED units, the daytime running lights are switched on.

Metrology Auto mode

DSO
Freeze frame

Channel A

Channel B

Measuring
mode

Trigger mode

Bandwidth
limitation

Channel

Skip 25.03.2008
13:32
431_097

If the onboard power supply control unit J519 sends a pulsed signal, the LEDs are operated at a reduced
luminosity and deployed as position lights. The LED units are currently unsuitable for repair or replacement.

Metrology Auto mode

DSO
Freeze frame

Channel A

Channel B

Measuring
mode

Trigger mode

Bandwidth
limitation

Position Time/div.

Skip 25.03.2008
13:32
431_098

43
 431
Vorsprung durch Technik www.audi.co.uk Service Training

Audi RS 6

Self-Study Programme 431

All rights reserved. Technical

specifications subject to
change without notice.

Copyright
AUDI AG
N/VK-35
Service.training@audi.de
Fax +49-7132/31-88488

AUDI AG
D-85045 Ingolstadt
Technical status: 04/08

Printed in Germany
A08.5S00.47.20