2017 AUDI A3 SEDAN relay

Trailer towing
Trailer towing
Driving with a trailer
General information
Your Audi was designed primarily for passenger
transportation.
If you plan to tow a trailer, please remember that
the additional load will affect durability, econo­
my and performance.
Trailer towing not on ly places more stress on the
ve hicle, it also ca lls for more concentration from
the dr iver.
F or this reason, always follow the operating and
driving instructions provided and use common
sense.
Technical requirements
Trailer hitch
Use a weight-carrying hitch conforming to the
gross tra iler weight. The hitch must be suitab le
for your veh icle and tra iler and must be mounted
securely on the vehicle's chassis at a technically
sound
locat ion . Use on ly a trailer hitch with a re­
movable ba ll mount . Always che ck with the t rail ­
er hitch man ufac tur er to make s ure t hat you are
using the co rrect hi tc h.
Do not use a bumper hitch.
The hitch must be installed in such a way that it
does not interfere with the impact -absorbing
bumper system. No mod ificat ions should be
made to the vehicle exhaust and b rake systems .
Fr om t ime to t ime, che ck tha t all hitch mo unti ng
bol ts rem ain securely f aste ned.
W hen you are not tow ing a tra iler, remove the
tra ile r hitc h ba ll mount . This prevents the hit ch
from caus ing damage s hou ld your veh icle be
s truck from be hind
c> ,&. .
Trailer brakes
If your trailer is equipped with a brak ing system,
check to be su re that it conforms to all regula­
tions .
120
The t rai ler hydraulic bra ke system must not be
directly connected to the vehicle's hydraulic
bra ke system.
Safety chains
A lways use s afety chains between you r vehi cle
and t he tra ile r.
Trailer lights
Traile r lights must meet all regula tions . B e s ure
to check w ith your Aud i dea le r fo r cor rect wir ing,
switches and relays .
Mirrors
If you are unable to see t he traffic behind you us­
i ng t he regular outs ide mir rors, then yo u
must in­
stall extended mirro rs . It is impo rtant that you
always have clear vision to the rear.
&, WARNING
Afte r remov ing the tr ailer hi tch, do not s to re
i t i n yo ur vehicle. In case o f su d den braking,
the hitch could fly fo rwa rd and injure you or
your passengers .
Operating instructions
Maximum trailer weight
A tra iler f or yo ur vehicle is lim ite d to a typical
class 1 or class 2 trailer.
Trailer load distribution
Be sure the load in the t rai le r i s he ld se curely in
pla ce to p revent i t from shi fting forward, bac k­
ward or si deways.
Never allow a passenger to ride in a trailer c> &.
in Driving instructions on page 121.
Engine cooling system
Towing a tra iler makes the engine work harder. It
is important that the cooling system's perform ­
ance is up to the additional load . Make sure tha t
the coo ling system has enoug h flu id.
Tire pressure
When towing a trailer, inf late the tires of your
vehicle to the tire pressure listed under "Full load" on the label
c> page 336. Inflate trailer

a, co ..... N
" N ..... 0 N > 00
Fuse assignment -interior
Fig. 301 Vehicle interior: fuse assignment
No. Equipment
Fl Ad
Blue engine components
F2 Seat adjustment
F3 Power top hyd
raulic pump
F4 Infotainment control panel, Infotainment
components
FS Gateway
F6 Selector lever (automat ic transmission)
F7 Climate/heating control, auxiliary heating,
rear window defogger relay
Electromechan ica l parking brake sw itch,
F8 light switch,
rain/light sensor, inte rior
lighting, anti-theft alarm system, diagnos -
tic connector, communication box
F9 Steering column sw itch module
Fl0 Infotainment system display
Fll Dr iver's side safety belt tens ioner
F12 Infotainment components
F13 Suspension
control control module, diag-
nostic connector
F14 Heating/air conditioning system blower
FlS Electronic steering column lock
No .
Fl6
F 17
Fl8
F 19
F20
F21
F2 3
F24
F 2S
F26
F 27
F28
F2 9
F 31
F32
F33
F34
F 3S
F36
F3 7
F38
F39
F 40
F41
F42
F43
F44
F47
F4 8
Fuses and bulbs
Equipment
Infotainment components
Instrument cluster
Rearview camera
Convenience access cont rol module
Engine components
Steering column, steering wheel heating
switch module
Right vehicle electrical system control
module
Panorama glass roof/power top control
module, power top latch
Driver's s ide front/rear power w indows
Seat heating
Sound-amplifier
Convertible top control module
Interior lights
Left vehicle electrical system control mod-
ule
Rearview camera, radar sensor control
module
A irbag
Button i llumination, interior sound, re-
versing light switch, temperature sensor,
coil for neck heating relay and socket relay
Fu nct ion lighting, headl ight range control,
a ir quality sensor, automatic dimming
rearview mirror
R ight headlight
l eft headlight
High-voltage battery
Passenger's s ide front/rear power win -
dows
Sockets Passenger's side safety belt tensioner
Cen tral locking components, windshield
washer system
Interior lights
Al l wheel drive
Rear w indow wiper
Outer sound actuator
365

Fuses and bulbs
No . Equipment
F49 Starter, clutch sensor, high-voltage bat-
tery, power electronics
FS3 Rear window defogger
The power seats* are protected via
circuit break­
ers
that automatically switch on after a few sec­
onds after the overload has been reduced.
Fuse assignment - engine compartment
F ig . 302 Engine co mpa rtment: fuse assignmen t
No. Equipment
Fl E
lectronic Stabilization Control (ESC)
F2 Electronic Stabilization Control ( ESC)
F3 Engine control module
Engine components, eng ine cooling, aux-
F4 ilia
ry heater coil relay (1+2), secondary
air injection pump relay
FS Engine components, tank system
F6 Brake light sensor
F7 Engine components, water pumps
FB Heat oxygen sensor
F9 Engine components, exhaust door, glow
time control module
FlO Fue l injectors, fuel control module
366
No . Equipment
Fll Auxiliary heater heating element 2
, en-
gine components
F l2 Auxiliary heater heating element 3
Fl3 Automatic transmission
F lS Horn
F l6 Ignition coils, CNG cut-off valve, power
and control electronics
Fl7 Elec
tronic Stabilization Control (ESC), en -
gine contro l module
Fl8 Terminal 30 (voltage
reference), battery
monitoring
F19 Windshield wipers
F20 Anti-theft alarm system
F 22 Terminal SO diagnosis, engine control
module
F2 3 Starter
F 24 Auxiliary heater heating element 1, brake
booster
F31 Vacuum pump, water pump
F33 Brake booster
F34 Brake booster
F35 A/C function relay
F37 Parking heater
Bulbs
Replacing light bulbs
For your safety, we recommend that you have
your authorized Audi dealer replace any bulbs for you.
It is becoming increasingly more and more diffi­
cu lt to replace vehicle light bulbs since in many
cases, other parts of the car must first be re­
moved before you are able to get to the bulb.
This applies especially to the light bulbs in the
front of your car which you can only reach
through the engine compartment.
Sheet meta l and bulb holders can have sharp
edges that can cause serious cuts, parts must be
correctly taken apa rt and then properly put back
together to help prevent breakage of parts and
..,.

a, a, ..... N
" N ..... 0 N > 00
(D Note
-Applying a higher voltage booster battery
will cause expensive damage to sensitive electronic components, such as control
units, relays, radio, etc.
- There must be no electrical contact between the vehicles as otherwise current could al­
ready start to flow as soon as the positive
(+) terminals are connected .
@ Tips
The discharged battery must be properly con­
nected to the vehicle's electrical system.
When jump starting or charging the battery,
never connect the negative ground cable to
the battery negative post because the battery
manager system must be able to detect the
battery's state of charge. Always connect the
negative ground cable to the negative ground
post of the battery manager control unit.
Using jump start cables
Connect the jump start cables in the exact order
described below.
Fig. 303 Engine compartment: connectors for jump start
cables and a charger
Fig . 304 Ju mp starting t he battery wit h another vehicle:
@ -dra in ed battery, @-starter batte ry
Emergency situations
Plug-in hybrid drive*: The connection points for
the jump start cables
vary ¢ page 104.
The battery is located to the left in the engine
compartment. The procedure for connecting
jump start cables that is described next is de­
signed to help jump start your vehicle.
Vehicle with drained battery:
.. Read the following carefully 9 page 368
.. Set the parking brake and place the se lector
lever in the P position .
.. Turn the ignition and electrical equipment off
in both vehicles .
Connecting positive terminal(+) to positive
terminal (+)
.. To reach the battery terminals, flip the battery
cover cap to the side¢ fig. 303 .
l. Clamp the end of the red jump start cab le to
the terminal
(D c> fig. 304 on the dead bat­
tery @¢ 0 in Starting with jumper cables
on page 369 .
2. Clamp the other end of the red jump start ca­
ble to the terminal @on the charging bat­
te ry @ .
Connecting negative terminal(-) to negative
terminal (-)
3. Clamp the black end of the jump start cab le
preferably at the ground point, or on the
negative terminal @ on the charging battery
®·
4. Clamp the other end of the black jump start
cable
only to the ground point @ on your
vehicle @c>(D.
5. Route the jump start cables so they cannot
get caught in the moving parts in the engine
compartment.
Starting the engine
6. Start the engine in the vehicle giving the
charge and let it run at idle .
7. Now start the engine in the vehicle with the
dead battery and wait two to three m inutes
until it "runs smoothly" .
8.
If the engine does not start, stop the start ing
procedure after 10 seconds and then repeat
it after approx imately 30 seconds.
Ill>
369