Haldex Clutch Pump
V181

Centrifugal lever mount

Haldex oil sump
609_019

Pressure build-up due to increased pump motor speed
As the pump motor speed increases, pressure builds up
inside the cylinder of the working piston. The centrifugal
levers now apply pressure to the valve balls and close the
gap. The rising pressure pushes the valve balls back
slightly, bringing the centrifugal force and the hydraulic
force into equilibrium.

The pressure inside the working piston, and therefore, the
amount of torque which can be transmitted, rises with
increasing motor speed.

Color key:
Vacuum
Un-pressurized
Pressure inside working piston cylinder
pressure < 638.1 psi (44 bar)

The valve ball is pushed more firmly
into the valve seat by the increased
speed of the centrifugal governor.

Centrifugal governor
with increased speed

609_021
48

Operation - extremely high pump motor speed
At high pump motor speeds, centrifugal levers apply pressure to the valve balls to such an extent that the pressure
inside the working piston cylinder rises to an unacceptable
level.

When the pressure exceeds 638.1 psi (44 bar), the pressure
relief valve opens and limits the system pressure.

Color key:
Vacuum
Un-pressurized
Excess pressure inside working piston cylinder
pressure > 638.1 psi (44 bar)
Pressure relief valve
opens

Overspeeding centrifugal governor

609_020

Pressure reduction due to decreased pump motor speed
When the pump motor speed slows, the centrifugal levers
exert less pressure on the valve balls. The pressure is
relieved through the open valve gap until the centrifugal
force and the hydraulic force are equal.
Color key:
Vacuum
Un-pressurized
Controlled pressure inside working piston cylinder

pressure < 638.1 psi (44 bar)

Pressure is relieved

Centrifugal governor
with reduced speed

609_050
49

Function diagram
J492

1

2

1

2

3

4

5

6

7

J492: All Wheel Drive Control Module
V181: Haldex Clutch Pump

8

Term. 31
Term. 30
Term. 15
V181
Suspension CAN bus, high
609_136

Suspension CAN bus, low

All Wheel Drive Control Module J492 communicates with
ABS/ESP Control Module J104 and Power Steering Control
Module J500 over the Suspension CAN bus.

It communicates with DSG Transmission Mechatronic J743,
Instrument Cluster Control Module J285, and Engine
Control Module J623 via Data Bus On Board Diagnostic
Interface J533.

Service
All Wheel Drive Control Module J492, Haldex Clutch Pump
V181 and flange for the propeller shaft are replaceable.

Various seals for the housing are also replaceable. Please
refer to the current repair literature for the latest information.
Haldex oil filler and
inspection plug

All Wheel Drive
Control Module
J492

Flange

Haldex oil drain
plug

Axle oil filler and
inspection plug
Axle oil drain plug

Haldex Clutch
Pump V181

609_137

Oil bleed port for double
shaft oil seal

Change intervals
The Haldex oil must be changed every 3 years, regardless of
mileage. The axle oil is not subject to a change interval.

Note

Haldex oil and rear axle oil are NOT the same. Do not mix them up during service work or irreparable damage
to components will occur.
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Diagnostics
All Wheel Drive Control Module J492 can be accessed with
the VAS Scan Tool via Address Word 22.
The following functions are available:

•
•
•
•

Control module identification
Specified/actual comparison
The validity of the software, the coding and the adaptation channels for the vehicle is checked.
Check DTC memory
Query and erase.
Output check diagnosis
To activate the output check diagnostics, the engine
must be running the coolant temperature less than
140 °F (60 °C).
If the output check diagnostic is operating, the
multi-plate clutch is kept closed up to a speed of 4 mph
(6 km/h). The vehicle must be driven below this speed
with the steering wheel at full lock (left or right). This
places a strain on the drive line causing the rear axle to
shudder. When the driven speed reaches 4 mph
(6 km/h), the clutch opens and the strain on the drive
line is relieved. This is an indication that the Haldex
coupling is working.

51

•

•
•

Basic setting
The basic setting function can be used to assign Haldex
Clutch Pump V181 to a matching characteristic curve
stored in All Wheel Drive Control Module J492.
Read MVBs
Replace control module
Includes all the work operations necessary to replace the
control module.

Replacing Haldex Clutch Pump V181
After replacing Haldex Clutch Pump V181, the first thing to
do is to correct the Haldex oil level. Next, an output check
diagnosis must be done on the vehicle while it is stationary
and then the oil level checked again. Finally, the basic
setting procedure must be performed.
Emergency running mode
Two temperature sensors are mounted on the printed
circuit board of control module J492 which monitor the
electronic components. The temperature of the multi-plate
clutches is calculated based on these temperature values.
If the calculated temperature exceeds a specific threshold,
the Haldex coupling is shut off. No indication or warning is
given to the driver.

Transmission selector mechanism
Y26

P

R

N

D/S

B1 B2 B3 B4 B5 B6 B7 B8 B9 B10

31 +/- P

R

N D/S

58d

N110

F319
J587
E313

A1 A2 A3 A4 A5 A6 A7 A8 A9 A10

Term. 31

Term. 30

P

Term. 15
Term. 58d

Powertrain CAN bus, low

609_138
609_139

Selector Lever Transmission Range Position
Display Unit Y26

Powertrain CAN bus, high

Selector lever position

E313 Selector Lever

If the selector lever is in P, switch F319 is open. It is closed
in all other positions. The information "selector lever in P",
"switch F319 open" cancels the ignition key removal lock
and is required to enable engine starting. If there is a short
circuit to ground in the circuit, the engine cannot be started
and the ignition key cannot be removed in models without
Advanced key.

F319 Selector Lever Park Position Lock Switch

Selector lever positions P, R, N, D/S and the tiptronic
signals “tiptronic gate recognition”, “tip plus” and “tip
minus” are recognized by Selector Lever Sensor System
Control Module J587 and sent to DSG Transmission
Mechatronic J743 via the Powertrain CAN bus.

J587 Selector Lever Sensor System Control Module
N110 Shift Lock Solenoid
Y26

Selector Lever Transmission Range Position Display
Unit

P

A discrete wire to Steering Column Electronics
Control Module J527 in vehicles without Advanced
key and to Electronic Steering Column Lock Control
Module J764 in vehicle with Advance key.

To shift from D to S (or S to D), the lever needs only to be
flicked backwards out of D/S once. The lever always springs
back to the D/S position.

Parking lock emergency release mechanism
The parking lock emergency release mechanism can be
accessed by unclipping the selector lever gate from the
center console and pushing the insulating foam to the side.

Emergency
release mechanism

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52

Fuel tanks
Various fuel systems are used in the Audi A3 ’13. Various
factors dictate which system is fitted in the vehicle:

Fuel tank for 1.8L TFSI Front track

Fuel tank for 2.0 TFSI quattro models

Fuel tank for 2.0 TDI Front track models with SCR tank

53

•
•
•

Engine type
quattro or front wheel drive
Climate zone of market

Exhaust system
1.8L TFSI and 2.0L TFSI engines

Close-coupled
main catalytic converter

Center muffler

Rear muffler

2.0l TDI engine

609_175

Oxidizing catalytic converter

Diesel particulate filter

Exhaust Flap Control Module
J883

Rear muffler

609_034
54

Running gear
Design concept
A design goal for running gear of the A3 sedan was to have a
finely balanced axle load distribution of 59% front to 41%
rear. The forward placement of the front axle in relation to
the body played a significant role in this accomplishment.
The use of the same components across the worldwide A3
model line-up was also of major consideration.

The application of the Audi ultra lightweight strategy was
also addressed by the use of aluminum axle components
and smaller wheel offsets.

Overview
ABS/ESP from Continental
TPMS standard

15“ or 16” inch brakes standard. 17“ inch brakes for S3 sedan

Tandem master brake cylinder with
single 10” or 11” diaphragm power
brake booster. (Engine dependent)

Distance Regulation Control
Module J428 when optional
ACC installed

Electro-mechanical steering is standard equipment. Dynamic steering to be offered at a later
date.

55

MacPherson strut front axle in combination with aluminum sub frame and
steering knuckle.

Four spoke steering wheel is standard. Different four
spoke and three spoke steering wheels available
depending on model and optional equipment selected

16” through 19” wheels available depending on model and options

15” brakes standard. 17” brakes standard for S3
Electronic Parking Brake is standard equipment.

Four-link rear suspension is standard on all
North American region vehicles except those
with the 2.0L TDI engine. (Delayed introduction.)

625_145

Reference
For more information about the A3 running gear, please refer to eSelf-Study Program 960143, The 2015 Audi A3 Running
Gear and Suspension System.

56

Suspension variations

625_147

Dynamic suspension

The Dynamic suspension is standard equipment for the 2015 A3 sedan.

Sport suspension

The sports suspension is optional. In models with sports suspension, ride height is 0.59 in (15 mm)
lower than in models with the standard suspension.

S line suspension

The ride height is lowered .98 in (25 mm) compared to the standard suspension. The tuning is more
sporty than the Sport suspension. The S line suspension comes with 18 inch wheels as standard.

Suspension system with
electronic damping control

This suspension system is available only on S3 models. It is based on the Audi magnetic ride system
currently used in other Audi models.

Tire Pressure Monitoring System
The 2015 Audi A3 uses the second generation tire pressure
monitoring system. It functions based on information from
the ABS/ESP control module. It is identical to the system
currently in use on other Audi models in terms of design,
operation, driver information provided, service operations
and diagnostics.

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57

Wheels and tires
Depending on equipment package, 16 and 17 inch wheels
are used in the standard trim. The 17 and 18 inch wheels
are optional.

A.

B.

E.

F.

The range of tires extends from the 205/60 R16 to the
225/40 R18. The "Tire Mobility System" is standard equipment; a minispare wheel is optional.

C.

D.

E.
A3

Wheels & Tires

Code
C0X

A. 7.5J x 17 5-spoke-Star-design
225/45 R17 all-season tires

H7K

B. 7.5J x 17 10-spoke Dynamic-design
225/45 R17 all-season tires

H7K

C. 8.0J x 18 10-spoke-Design, Audi exclusive
225/40 R18 all-season tires
225/40 R18 summer performance tires
D. 8.0J x 19 5-arm-Wing-design, Anthracite
polished 235/35 R19 summer
performance tires
E. 8.0J x 18 5-arm double spoke S3 design
225/40 R18 summer performance tires
225/40 R18 all-season tires
F. 8.0J x 19 5-parallel spoke Cast Aluminum design
225/35 R19 summer performance tires

C5I

S3

Package

1.8T

2.0T

2.0TDI

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