奥迪A4车辆电子控制单元J519

Service

Audi A4

Electrical system

Vehicle electrical system control unit (J 519)

Contents:

General function description Page 3

Light control Page 5

Light monitoring Page 7

Turn signal / hazard light control Page 9

Brake light control Page 10

Activation relay Page 11

Wiper / wash control Page 11

SG for trailer recognition Page 13

Emergency operation Page 15

Fault finding Page 16

Diagnosis Page 17

The trainer information is structured for the

self study programme 254 – Audi A4 2001

is not a

workshop manual.

For maintenance and repair operation

please use the current

technical literature.

General function description

Vehicle electrical system control unit

By using a vehicle electrical system control unit,

the vehicle weight could be reduced due to less

cable and a lower number of relays and control

units.

The functions

- Wiper activation

- Drive light activation with lamp control

- Horn activation

- Load-reduction relay activation

- Turn signal and hazard light activation

- Brake light activation

are taken over by the vehicle electrical system

control unit as a central unit.

Signal transmission is via the CAN bus

convenience with a speed of 100 kBaud.

There is an active data exchange between

- Steering column electronics in switch module

- Dash panel insert (with Gateway to the CAN

bus drive)

- Steering wheel electronics module

- Central convenience electronics (CCE) with

the relevant door modules

- Control unit for trailer recognition

- Vehicle electrical system control unit

- Multi-function control unit for special vehicles

Control unit versions

Low-line for standard equipment

8E0 907 279 (C)

Low-line for vehicle with headlight

washer system

8E0 907 279 A (D)

High-line for vehicle with DIS

(driver information system)

8E0 907 279 B (E) Gateway

Passenger

door module

Driver door

door module

Rear

door module

Air

conditioner

Trailer recog-

nition CU

Additional

heater

Tyre pressure

check system

Parking aid

Multi-function

control unit

Steering

column

electronics

Vehicle

electrical

system

control unit

Gateway

Driver seat

memory

Active data

exchange

Steering

wheel

electronics

Fitting location:

Front left footwell below dash panel cross member – instead of the earlier central electrics

Country versions

Depending on country, various regulations apply for the vehicle lighting system.

The various light activations are stored in the EEPROM and can be adapted to the relevant specific regulations via the coding.

Vehicles that are exported into these countries are generally equipped with the high-line version even if a driver information system is not fitted.

Activated components

In the low-line version, the following functions are performed by the vehicle electrical system control unit:

- Hazard light system

- Turn signal

- Window wiper

- Washer pump incl. rear wiper activation in Avant

- Activation of horn and load-reduction relay

- HWS (headlight washer system)

- Parking light, right *

- Parking light, left *

- Main beams, right

- Main beams, left

- Turn signal, right **

- Turn signal, left **

- Number plate lamps

* front and rear are activated together

** front, rear and side are activated together

In the high-line version the lighting elements are activated individually, including those marked with * and ** in the low-line version.

The following lighting units are activated additionally via the processor:- Dipped beam headlights, left,- Dipped beam headlights, right,- Fog light, left,- Fog light, right,- Brake lights, left, centre and right,- Reversing light, left,- Reversing light, right,- Rear fog light.

Voltage supply Normal operation min. U batt = 9 V max. U batt = 15 Volt

An increased supply voltage of up to 6 Volt is permitted for the horn, turn signal activation and wiper washer system with HWS functions.

Light control

Rear light

High-line

In vehicles with driver information system, the brake light filament in the 2-filament bulb is used as the rear light. For this purpose, the 21 watt

lamp is activated via a PWM signal to minimise the lighting power. Thus, both rear lights are capable of diagnosis without additional semiconductor elements and wiring.

A defective 2-filament lamp is indicated by the failure of the 21 watt brake light filament.In the low-line version the contact for the 5 watt glow filament is present and activated.

Brake actuated

Side light ON

Encodeable daylight driving lights

The coding for the relevant country can be found in the coding table in chapter “Diagnosis”.Example: In vehicles destined for Denmark,Finland, Norway and Sweden with daylight

driving lights without Xenon headlights, the dipped beam headlights and sidelights are dimmed to 92%.

When dipped beam headlights are switched on,the full lighting output is available.

Headlight range control

The headlight range control is dynamic and is activated by a separate control unit. The control unit is activated by a conventional connection to the rotary light control (terminal 56b.)Reversing light activation Low-line

With conventional wiring via the reverse gear switch or the multi-function switch with multitronic/automatic gearbox.

High-line

For the reversing light activation, the signals are transmitted to the vehicle electrical system control unit via the convenience CAN bus from the central convenience electronics. There, the direct input from the reverse gear switch or multi-function switch is available.

Daylight driving

lights

Dipped beam

Light switch

Light monitoring

The light monitoring differentiates between the test types cold and warm monitoring.Function

With ignition ON, the lamp circuit is activated 5 times for 200μsec in a cycle of 200 msec.In electrical consumers with an output >50 watt, this is recognised via an current detection in the semiconductor element.

For the other electrical consumers, only an open or closed circuit is detected.

Cold monitoring During cold monitoring, a test current is applied to

the relevant lighting circuit, each time the ignition

is switched ON. This test current is checked via a current threshold measurement or status test (circuit open/closed). This means that individual lamps can be recognised as defective even before initial operation.

Warm monitoring

If a lamp fails after cold monitoring was OK, a fault is only displayed or stored after this lighting circuit has been switched on.

Important:

This is only intended an illustration of the circuit test.

Open circuit cannot be detected by means of a voltage measurement.

High-line

The current value thresholds are:

For the low line version, these lighting circuits can be conventionally activated via the rotary light control.

For Xenon headlights, cold monitoring cannot be performed due to the ignition control unit.The third brake light and number plate lamp can only be

detected in the case of complete failure, as the lighting components are connected in parallel.If a fault is detected, the fault is stored in the vehicle electrical system control unit.

High-line with driver information system

The defective lamp is accurately defined in the driver information display, e.g. dipped beam

headlights front left, in conjunction with the yellow warning symbol “lamp defective”.

M o n i t o r i n g

D i p p e d b e a m

M a i n b e a m

F o g l i g h t

Cold 3.7 A 2.0 A 2.0 A Warm 2.0 A 1.0 A 2.0 A

Turn signal and hazard light activation

Functions

- Turn signal flashing - Motorway flashing

- Hazard warning flashing - Crash flashing - ATWS flashing

- CL flashing when opening/closing

- Key learn flashing for radio key adaption - Panic flashing (USA)-

Taxi alarm flashing

Turn signal flashing

If a side or trailer turn signal lamp fails, the turn signal frequency is not influenced.

Motorway flashing

If the turn signal switch is actuated for <1 sec. the turn signal function is activated for 3 flashing cycles.

Hazard warning flashing

There are 2 operating modes: Sequence

flashing via terminal 15 – normal flash in light/dark ratio of 55 to 45.

Flashing via terminal 30 – slow flash in ratio of 35

to 65 to minimise the current consumption with ignition OFF.

A “stuck” hazard warning switch is detected by the self-diagnosis after 30 seconds and stored in the

fault memory.

With terminal 30

With terminal 15

The locating light of the hazard warning switch is only switched off when the CAN convenience bus switches to sleep mode.

The functions - ATWS flashing

(anti-theft warning system)- CL flashing when opening/closing - Key learn flashing for radio key adaption - Crash flashing - Panic flashing (USA only)

are specified by the central convenience

electronics (CCE) and transmitted via the CAN convenience bus.

Taxi alarm flashing

Taxi alarm flashing is activated by an independent multi-function control unit which is connected to the convenience bus.

The turn signal clicking is generated by an integral acoustic relay in the dash panel insert and can only be heard during turn signal flashing.

Brake light activation

High-line

The brake light activation is connected from

terminal 30 via the brake light switch to the control unit

for the vehicle electrical system. The brake pedal switch is used as a redundant safety switch.

Low-line

The brake light activation is effected via

conventionally fused wiring via the brake light switch.

High-Line

Activation relay

The activation for the external horn and load-

reduction relay is effected directly by the vehicle

electrical system control unit. The switch-on

commands are transmitted from the relevant

switch, via the convenience CAN bus from the

steering column switch module.

the HWS relay are now integrated into the vehicle

electrical system control unit and are controlled by

the microprocessor.

Wiper/wash functions

?Flick wiping Array?Interval wiping – speed dependent in

4 stages

?Stage 1

?Stage 2

?Washing – depending on actuating time of

wiper switch (pull) the following cycles are

activated

Actuating time Wiper cycles

1 x < 500 ms1

1 x > 500 ms2

2 x < 500 ms2

?Re-wiping

5 seconds after completion of wiper/wash function,

automatic re-wiping in stage 1 is performed

Blocking detection

Blocking detection is intended to protect the wiper motor.

With switch in ON position,

?if a current > 32 A is detected, the wiper motor switches off immediately

or

?if no level change occurs at terminal 31b (cam contact) within 4 seconds, the system

switches off. Renewed activation for 4

seconds in stage 1 is effected after a pause

of 12 seconds. This procedure is repeated

cyclically until the wiper switch is set to OFF. With switch in OFF position,

?if after ignition ON it is recognised that

terminal 31b (cam contact) is not in rest

position, the wiper motor is activated in stage

1 (max. 4 seconds) until the rest position is

recognised via terminal 31b. This procedure

is activated only once within an ignition ON

phase.

Headlight washer system (HWS)

The activation of HWS is via an internal relay, with an activation period of 800 ms per wiper cycle

when

- the dipped beam headlights are switched on,

- the windscreen washer is active and

- the wash water level is OK.

The HWS is switched on with a delay of 900 ms if

all conditions are met after the front washing.

The function link with the wash water level warning in the check system is intended to save water, so that the window washer function remains functional even if the level is low. Additionally, this is a protection feature for the HWS pump in order to avoid the shortening of the service life by running dry.

Control unit for trailer recognition J345

For operation with trailer, a control unit for trailer recognition J345 is required, which can evaluate the CAN convenience messages for the vehicle lighting and transmit them to the power outputs.

Trailer recognition

The trailer recognition is performed every 10ms through a continuous, cyclical powering of the - left turn signal and/or the brake light, with

ignition ON.or - with ignition OFF via the brake light.

If one of the two power circuits is OK, trailer operation is recognised by the control unit.

.

Important : Illustration only valid for

Blinklicht links

If the vehicle is parked with the trailer connected (ignition OFF), the trailer recognition is continued.

Lamp failure can only be detected if the relevant circuit is open.

If, for example, the brake light lamp has failed, the control unit cannot detect the failure due to the parallel activation of two light components.High-line

An open trailer circuit is displayed in the driver information system as, for example, “Trailer turn signal, left” together with the yellow warning symbol for the lamp defect.

The power output stages in the control unit for trailer recognition are designed for maximum power as follows:

Side light, left 10 x 5W Side light, right 10 x 5W Turn signal, left 2 x 21W Turn signal, right 2 x 21W Brake light 4 x 21W Rear fog light 2 x 21W

Reversing light 2 x 21W The above-mentioned values are maximum

values. If these values are exceeded, a fault is set or indicated due the increased current consumption.

Ignition off

and CAN bus convenience active

Ignition off

and CAN bus convenience in sleep mode

Important : Illustration valid for open turn signal circuits (left side)

The trailer recognition control unit is only able to

perform self-diagnosis indirectly.

In case of faults only a defective trailer recognition

control unit is recognised and is stored in the fault

memory as “01517 – CONTROL UNIT FOR

TRAILER RECOGNITION DEFECTIVE”.

If a trailer coupling is retrofitted, it is imperative

that a trailer recognition control unit is installed at

the intended positions, as the socket wiring cannot

be connected directly to the output wiring. Fault

detection would occur due to increased current

consumption in the vehicle electrical system

control unit.

Emergency operation of trailer recognition control unit

If the CAN bus (high and low line) is interrupted,

both rear lights are activated via a safety circuit. Emergency operation of vehicle electrical system control unit

If the processor fails the

- dipped beam headlights (high line only) and

- side light

are maintained via a redundant signal path.

If an undefined fault is present in the rotary light

control, the side light and dipped beam headlights

switch on automatically after approx. 2 seconds.

The brake light function is also ensured via an

emergency circuit.

Fault finding

High-line

During fault finding, difficulties may be

encountered as the various power circuits are activated differently.

In certain circuits, the voltage measurement in an open line, defective bulbs or similar cannot be performed.

This applies to the following circuits:- Rear light -

Front side light -

Reversing lights -

Rear fog light

Side light

Reversing light

Rear fog light

Rear light

Diagnosis

Address word

The address word for the vehicle electrical system

control unit is 09 – electronic central electrics or

under vehicle electrical system (high/low-line).

Entry into fault memory (02)

If the fault

is displayed, an adaption of the vehicle

electrical system control unit to the vehicle

must be performed.

Refer to “Adaption”

Final control diagnosis (03)

Coding (07)

Not assigned 0

Light sensor *

0= without light sensor 1= with light sensor

X Trailer coupling

0= without TC 1= with TC

X Headlight system *

0= Halogen headlights 1= Xenon headlights

X Country equipment *

1= Rest of the world

2= Rest of the world –northern countries 3= USA 4= Canada 5=Denmark

6=Special vehicles

X

* only codeable for high-line

Actuator

Low/ High

Turn signal, left X X Turn signal, right X X Hazard warning light X X Side light, left X X Side light, right X X Rear light, left X X Rear light, right X X Main beam, left X X Main beam, right X X Number plate light X X Wiper, stage 1X X Wiper, stage 2

X X Rear screen wiper motor X X Washer pump, front X X Washer pump, rear

X X Windscreen washer pump X X Relay activation, horn X

X Dipped beam, left X Dipped beam, right X Fog light, left X Fog light, right

X Reversing light, left X Reversing light, right

X Brake lights (left, right, centre)X Rear fog light

X

Measured value blocks (08)

A chassis number is stored in channel 81 and is

used for the anti-theft security.

Please observe the procedure as described in

“Adaption”.

OUTPUT SIGNALS

001Voltage supply Horn Terminal 75HWS

on Off on

Off

on

Off

002Turn signal

Front left Turn signal

Rear left

Turn signal

Front right

Turn signal

Rear right

on off on

off

on

off

on

off

003side light

Front left Side light

Rear left

Side light

Front right

Side light

Rear right

on off on

off

on

off

on

off

004Main beam

left Main beam

right

Number plate light Function display

Hazard warning

lights

on off on

off

on

off

on

off

005Wiper

front Washer

front

Wiper

rear

Washer

rear

off Stage 1 Stage 2on

off

on

off

on

off

INPUT SIGNALS

006Rotary light control Hazard warning

switch sensor

Terminal 75Cam contact

off

Stage 1 (side light) Stage 2 (dipped beams) Stage 3 (not assigned) Stage 4 (fog light)

Stage 5 (RFL)

actuated

not actuated

on

off

on

off