both relays to ground. The relays then close their switching
contacts and terminal 50 is supplied to the starter.
A protected diagnostic line allows the Engine Control
Module to check whether terminal 50 has actually been
switched.

The NO contact is deactivated by removing the ignition key
from the switch.

Terminal 75
No separate terminal 75 relay is installed in the 2015 Audi
A3. Other control modules receive the current status of
terminal 75 from Steering Column Electronics Control
Module J527.

26

Terminal management with Audi advanced key

J518

10A

E408

Gear selector position "P"

Terminal 30

Convenience CAN bus

Steering Column Electronics
Control Module J764

Terminal 15 request 1
Terminal 15 request 2
NO contact

Vehicle
Electrical
System
Control
Module
J519

Terminal 50 request

Terminal 30

Terminal 15

Terminal 15

Terminal 50 diagnostics

Terminal 50

Powertrain CAN bus

Engine Control
Module J623

611_023

Key:
E408

Access/Start Authorization Button

J329

Terminal 15 Power Supply Relay

J906

Starter relay 1

J907

Starter relay 2

27

Steering Column Electronics Control
Module J764
When the vehicle has Audi advanced key, Access/Start
Authorization Button E408 is installed in place of the
ignition switch. The ignition is switched on and off and the
engine started or switched off with this button.

Access/Start Authorization Button
E408
E408 has two micro-switches. Both are monitored by Steering Column Electronics Control Module J764. The microswitches are actuated as long as the button is pressed.
J764 determines the current status of terminals 15, 50, 75
and the NO contact by continuously monitoring the microswitches. The status of these terminals is transmitted to
other control modules over the Convenience CAN bus.

Terminal 50
The Engine Control Module receives the request to start
from J764. The request is sent across discrete wires as well
as on the Convenience CAN bus. The ECM activates both
Starter Relays J906 and J907.
To do this, the ECM closes its internal switches and connects both relays to ground. Both relays then close their
switching contacts and terminal 50 is available to the
starter.
A protected diagnostic wire allows the ECM to check
whether terminal 50 has been switched.

Terminal 75
A separate ‘terminal 75’ relay is no longer installed in the
A3. Other control modules receive the current status of
terminal 75 from Electronic Steering Column Lock Control
Module J764 via the Convenience CAN bus.

If either of the micro-switches in E408 becomes faulty, the
ignition can no longer be switched on nor the vehicle
engine started. If this occurs while the ignition is switched
on and the engine running, it can be switched off one more
time only.

NO contact and terminal 15
After pressing Access/Start Authorization Button E408, a
check is made of the key. If the check is successful, Steering
Column Electronic Control Module J764 activates the NO
contact and the ignition switches on.
To switch on the ignition, voltage is applied to the following three signal lines:
• Terminal 15 request 1
• Terminal 15 request 2
• NO contact

Vehicle Electrical System Control
Module J519
The three signal wires are monitored by J519. If voltage is
present in at least two of the three, Terminal 15 Start Relay
J329 is activated and the ignition switches on. It is still
possible to start the engine in the event of and open circuit
in one of the three signal wires.

28

Interior lighting
Two interior lighting scenarios are possible for the 2015 A3
depending on model and option choices.
1. Basic interior lights (QQ5), standard on Premium and Premium
Plus models.

and
2. Interior light package (QQ4), available with the Convenience
package of the A3 Premium Plus and standard equipment on
the A3 Prestige model.

Standard interior light trim (QQ5)
In the basic trim, the lights in the vehicle interior use bulb
technology. The lights are located in the overhead module,
luggage compartment and glove compartment. The lights
are powered by a switched terminal 30.

There are no door warning lights. Red reflectors are
installed in their place.

Vanity lights

Vehicle Electrical
System Control
Module J519

Terminal 30g

Door contact
signal

Ground

Terminal 30g

Door contact signal

Convenience CAN bus

with bulbs

611_024

Key:
1

Vanity lights, left or right

2

Light in glove compartment

3

Luggage compartment light

4

Interior lights in overhead module

5

Rear lights

29

Interior light package QQ4
Interior light package QQ4 is available on the Premium A3
model when the optional Convenience package is installed.
It is standard equipment on the A3 Prestige model. When
this light package is installed on a vehicle with MMI Navigation plus or MMI Navigation plus with Audi connect, the
interior lights can regulated via the MMI under the Car
menu.

background light. In addition, the vehicle is equipped with
four LED footwell lights and a cupholder light. The vanity
lights also use LED technology.

When interior light package QQ4 is ordered, an LED module
is installed in the front and rear light housings. The LED
overhead module has two reading lights and a central

The speaker lighting is only available when MMI Navigation
plus or MMI Navigation plus with Audi connect is ordered.

Terminal 30g
Door contact signal

Active door warning lights using conventional bulbs and
door entry lights using LED are installed in the doors. The
inner door handle on the driver’s door is also illuminated.

Vehicle Electrical
System Control
Module J519

Terminal 30g

Convenience CAN bus

LED
overhead
module

Rear
lights

Driver Side Rear
Door Control
Module J926

Driver Door Control
Module J386

Passenger Door
Control Module J387

Passenger Side
Rear Door Control
Module J927

611_025

with LED
technology

with bulbs

Key:
1
2
3
4a
4b
5
6

Vanity lights, left or right
Light in glove compartment
Luggage compartment light
Reading lights in LED overhead module
Rear lights
Background light in LED overhead module
Cupholder light

7
8
10
11
12
13

Front footwell lights
Rear footwell lights
Active door warning light
Door entry light
Inner door handle light
Sound loudspeaker lighting

On vehicles equipped with bi-xenon headlights, the
Cupholder light is activated via pin B2 of J519.

30

Setting options in the Car menu
A customer can adjust the brightness of the background
lights via the MMI Car menu. It is located under Vehicle
settings, Background lighting. There are three adjustable
zones:
•
•
•

Front zone
Footwell zone
Door zone

The actual zones displayed in the MMI menu depends on
what optional equipment has been ordered.

If at least two zones are available as options in the MMI
menu, the setting option "All zones" is offered and allows
all zones to have the same setting.

The following optional equipment displays the following
zones in the MMI menu:
1. Interior light package

ð

"Front" & "footwell" zones

2. Premium Sound

ð

"Door" zone

611_027a

Only the background lights react to brightness adjustments
made via the Car menu.
The following lights are integrated in the background
lighting:
• Footwell lights
• Cupholder light
• Speaker lights

31

Power supply to interior and background lights
Terminal 58
The task of terminal 58 is to control the instrument lighting, display lighting and the locating lights in the buttons
and switches. The lighting effect is dependent on the
current brightness level of the vehicle and the customer
setting.

The customer can set the desired basic brightness of the
interior lighting using the retractable control button on the
light switch. The setting is by the LIN bus to J519. The
duty cycle of the pulse width modulated (PWM) signals of
terminals 58xs, 58xt and 58xd are calculated from both
input variables.

The brightness of the vehicle interior is measured by a
photosensor in the Instrument Cluster. The photosensor
signal is sent to Vehicle Electrical System Control Module
J519 via the Convenience CAN bus.

Instrument Cluster
Control Module
J285

Light Switch
E1

Photosensor

Potentiometer

Brightness
Photosensor

Resistance
Potentiometer

Terminals 58xs, 58xt and 58xd

Vehicle Electrical System Control Module J519

Photosensor brightness

Terminal 58xs

Potentiometer

Terminal 58xt

Terminal 58xs

Terminal 58xt

Locating light
Switch
Lighting
Hazard warning
light switch

Terminal 58xd

611_028

A distinction is made between three different versions of terminal 58:
Terminal 58xs (formerly terminal 58s):

Switch locating light

Terminal 58xt (formerly terminal 58t):

Switch locating light with when door opened/when key removed from ignition

Terminal 58xd (formerly terminal 58d):

Display and instrument lighting

32

Terminals 58xs and 58xd are active as long as the side lights or low beam headlights are switched on.
Terminal 58xt corresponds to terminal 58xs with additional
advance and trail function. It is pre-activated if, for
example, one of the following events occurs:

Terminal 58xt is deactivated if, for example, the following
event occurs:
• The ignition is switched off.

• Vehicle is unlocked
• A vehicle door is opened
• The ignition is switched on

Vehicle Electrical System Control Module 1 J519 transfers
the values calculated for terminals 58xs, 58xt, and 58xd to
other control modules via the CAN bus. The control
modules to which lights or displays are connected generate
a corresponding PWM signal from the values to control the
brightness.

The light intensity is based on the duty cycle of the PWM
signal.

Switched terminal 30 (terminal 30g)
The signal for switched terminal 30 is generated by Vehicle Electrical System Control Module 1 J519. This is used only to
power lights in the vehicle interior.
The following events lead to the activation of terminal 30g:
• Switching on the ignition
• Manual activation of lights powered via terminal 30g

The following events lead to the deactivation of terminal
30g:
• The after-run time of terminal 30g has expired
(timer starts when ignition is switched off)

• Unlocking a vehicle door or the rear trunk lid
• The vehicle is locked:
• Opening a vehicle door or the rear trunk lid
• no vehicle door is open

• Removing the ignition key
• Turning the rotary light switch

and
• the rear trunk lid is closed
and
• the interior light is dimmed

The following lights are powered by a switched terminal 30 from J519:
• Light in glove compartment

• Vanity lights in the sun visors

• Luggage compartment light

• Interior light bulb in overhead module

• Footwell lights

• Reading lights

33

Driver assistance systems
Rearview Camera R189
A back-up camera is optional for the A3 model line up for
the first time.