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49
There are three control unit versions:
– "lowline" for the standard version
– "lowline" for vehicles with headlight
washer system
– "highline" for vehicles with driver informa-
tion system
The following functions are available with the
"lowline" version:
– Wash/wipe control and interval
– Hazard warning and turn signal control
– Actuation of horn and load-reduction relay
– Parking light left/right
– Side light left/right
– Main beam left/right and headlight flasher
– Number plate lightThe "highline" version implements the driver
information system function and also
performs the following control functions:
– Driving light and dipped beam left/right,
– Fog lights and rear lights,
– Reversing lights,
– Brake lights
with separate outputs to each of the individ-
ual consumers.
Light control
In the highline version, light control is trans-
mitted from the steering column switch
module or directly from the rotary light
control, via the convenience data bus, to the
vehicle electrical system control unit.
Parking lights
Main beam
Headlight flasher Side lights
Dipped beam
*
Fog lights
*
Rear fog lights
*
*
In the "lowline" version, the components marked with
an asterisk are connected via conventional wiring and
fuses, directly to the lighting units.
Control unit for
vehicle electrical
system J519
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50
Auxiliary signals
1 CAN high convenience
2 CAN low convenience
3 Terminal 75
4 not fitted with trailer coupling
5 only with trailer coupling
6 Automatic gearbox "multitronic"
7 Manual gearbox
A
U
X
Y
Z
Electrical system
"lowline" version
Components
E1 Light switch
E3 Hazard warning light switch
F Brake light switch
F4 Reversing light switch
F216 Contact switch for switchable
rear fog lights
H2 Treble horn
H7 Bass horn
J4 Relay for dual tone horn
J59 Load-reduction relay for x contact
J345 Control unit for trailer recognition
J446 Control unit for parking aid
J519 Control unit for vehicle electrical
system
L22 Bulb for fog light, left
L23 Bulb for fog light, right
L46 Bulb for rear fog light, left
L47 Bulb for rear fog light, right
M1 Bulb for side light, left
M2 Bulb for rear light, right
M3 Bulb for side light, right
M4 Bulb for rear light, left
M5 Bulb for turn signal light, front left
M6 Bulb for turn signal light, rear left
M7 Bulb for turn signal light, front right
M8 Bulb for turn signal light, rear right
M9 Bulb for brake light, left
M10 Bulb for brake light, right
M16 Bulb for reversing light, left
M17 Bulb for reversing light, right
M18 Bulb for side turn signal light, left
M19 Bulb for side turn signal light, right
M25 Bulb for high-level brake light
M29 Bulb for dipped beam headlight, left
M30 Bulb for main beam headlight, left
M31 Bulb for dipped beam headlight, right
M32 Bulb for main beam headlight, right
S Fuses
U10 Socket for trailer operation
V Windscreen wiper motor
V5 Windscreen washer pump
Colour coding
= Input signal
= Output signal
= Positive power supply
= Earth
= CAN-BUS
V11 Pump for headlight washer
conditioning system
V48 Servo motor for headlight range
control, left
V49 Servo motor for headlight range
control, right
X Number plate lights
Connection within the
functional diagram
Functional diagram
Control unit for vehicle
electrical system J519
{
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20A S36
30A
30
J59
X E1
L22 L23
H2
H7
J4
Y
U
30
Y
15
01
2
58sL47 M17 M10 M2 M8 M19 M7 M3 M32 M31 V49
3
M25
F
U
7
15
in out
S19
15A
S20
15A
Z
S40
25A
J345
XS21
15A
S27
30A
S77
30A
F216
M
M
L46 M16 M9 M4 M6 M18
M5 M1 M30 M29 V48 V5 V11
M
F4 X X
VE3
J519
S14
10A
4
Z
J446
U10
6
2
1
X
A
5
5
5
5
A
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52
Auxiliary signals
1 CAN high convenience
2 CAN low convenience
3 Terminal 75
4 Terminal 31
U Connection within the functional
diagram V11 Pump for headlight washer
conditioning system
V48 Servo motor for headlight range
control, left
V49 Servo motor for headlight range
control, right
X Number plate light
"highline" version
Components
E1 Light switch
E3 Hazard warning light switch
F Brake light switch
F216 Contact switch for switchable
rear fog lights
H2 Treble horn
H7 Bass horn
J4 Relay for dual tone horn
J59 Load-reduction relay for x contact
J345 Control unit for trailer recognition
J446 Control unit for parking aid
J519 Control unit for vehicle electrical
system
L22 Bulb for fog light, left
L23 Bulb for fog light, right
L46 Bulb for rear fog light, left
L47 Bulb for rear fog light, right
M1 Bulb for side light, left
M2 Bulb for rear light, right
M3 Bulb for side light, right
M4 Bulb for rear light, left
M5 Bulb for turn signal light, front left
M6 Bulb for turn signal light, rear left
M7 Bulb for turn signal light, front right
M8 Bulb for turn signal light, rear right
M9 Bulb for brake light, left
M10 Bulb for brake light, right
M16 Bulb for reversing light, left
M17 Bulb for reversing light, right
M18 Bulb for side turn signal light, left
M19 Bulb for side turn signal light, right
M25 Bulb for high-level brake light
M29 Bulb for dipped beam headlight, left
M30 Bulb for main beam headlight, left
M31 Bulb for dipped beam headlight, right
M32 Bulb for main beam headlight, right
S Fuses
U10 Socket for trailer operation
V Windscreen wiper motor
V5 Windscreen washer pump
Electrical system
Colour coding
= Input signal
= Output signal
= Positive power supply
= Earth
= CAN-BUS
Functional diagram
Control unit for vehicle
electrical system J519
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20A S36
30A
30
J59
E1
L22 L23
H2
H7
J4
2
U
30
01
2
58sL47 M17 M10 M2 M8 M19 M7 M3 M32 M31 V49
M25
F
15
15
A
15
1
M2
in out
S40
25A
J345
S27
30A
S77
30A
F216
M
M
L46 M16 M9 M4 M6 M18
M5 M1 M30 M29 V48 V5 V11
M
X X
VE3
4
J519
S14
10A
J446
U10
U
3
S7
10A
M4
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54
5 V/Div.=10 ms/Div.
0 T
Electrical system
In the "highline" version of the vehicle electri-
cal system control unit, only the 21 watt
filament of the two-phase bulb for the brake
and rear light is used.
With lights switched on and non-actuated
brakes, the power rating is reduced to 5 watts
by a pulse-width modulated signal via the
vehicle electrical system control unit J519.
Thus a self-diagnosis/driver information
system (FIS) is possible for the second rear
light.
A defective brake light would be indicated in
FIS.
In vehicles with the "highline" version, national
lighting regulations can be adapted via
coding.For non-plausible condition of the rotary
light control, the side lights and low beam
are switched on automatically by the vehi-
cle electrical system control unit in the
"highline" version.
SSP254_080
Measuring equipment
DSORecorder operation
Photo
Channel A
Channel B
Measuring
mode
Cursor 1
Cursor 2
Multimeter
Help Print
PositionTime/Div.
Trigger mode
Skip
Brake not actuatedBrake actuated
Rear lights on:
5 V/Div.=2 s/Div.
0
Electrical fault finding
In certain lighting circuits, an open-circuit
voltage measurement using the Multimeter is
not possible, as the semi-conductor elements
are clocked until the circuit is again closed.
For defective bulbs which are operated via the
vehicle electrical system control unit J519, no
permanent fault storage is effected, but only
for the period of the fault.
This means that the fault memory must not
be erased after changing a defective bulb.
Measuring equipment
DSORecorder operation
Photo
Channel A
Channel B
Measuring
mode
Cursor 1
Cursor 2
Multimeter
Help Print Ve h i c l e
self-diagnosis
Position Time/Div.
Reversing lamp on:
1 - bulb illuminates
2 - bulb failure
3 - clock frequency of power output
1
2
3
SSP254_052
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55
The hazard warning flasher signal is control-
led separately by the vehicle electrical system
control unit, via the hazard warning flasher
button.
If, during hazard warning flashing, the turn
signal flasher is actuated, e.g. during towing,
the hazard warning lights lose their priority
for this period.
The turn signal clicking is generated by an
integral acoustic relay in the dash panel
insert.
Turn signal/hazard warning light control
The functions:
– Anti-theft alarm flasher
– Central locking system flasher when
opening/closing
– Key-learn flasher for key adaption
– Crash flasher
– Panic flasher (USA only)
are specified by the central convenience elec-
tronics and transmitted via the convenience
data bus to the vehicle electrical system con-
trol unit, which then executes the "com-
mands".
The signal for turn signal flashing or motor-
way flashing is output via the steering column
switch module and executed by the vehicle
electrical system control unit.
For active hazard warning flasher with
ignition OFF, the flasher bulbs are actu-
ated for a shorter period in order to mini-
mise current consumption.
Motorway flashing is detected by the vehicle
electrical system control unit when the turn
signal lever is pressed and this triggers a tri-
ple turn signal flash.
Turn signal light, right
Turn signal light, left
Turn signal light, right
Turn signal light, left
SSP254_077
SSP254_078
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Electrical system
The windscreen wash/wipe relays are inte-
grated into the vehicle electrical system
control unit J519.
The washer fluid reservoir is a two-part
design for easier removal and installation.
An additional sensor is fitted for vehicles with
headlight washer system (HWS). In the
"highline" version, this is also used for the
Check system.
The purpose of the sensor, is to switch off the
HWS pump via the vehicle electrical system
control unit.
This prevents the pump running dry.
Wash/wipe system
The wash/wipe system is equipped with the
speed-dependent 4-stage interval system.
A new feature is the re-wipe function for the
windscreen washer system.
Re-wiping occurs automatically 5 seconds
after the wash procedure is completed.
Headlight washer sys-
tem pump V11
Windscreen and
rear screen washer
pump V58
Windscreen washer fluid
level sender G33 Reservoir in engine
compartment
Reservoir in front left
wheel housing
Connected
SSP254_024