check engine light AUDI A6 2015 User Guide

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Child safety lock for
the rear doors
The power child safety lock locks the rear win­
dows and prevent the rear doors from being
opened from the inside .
Fig. 30 Sectio n fr om driv er' s door : child sa fety lock
b uttons
• To activate the child safety lock for the left/
right rear door, press the left/right button
[!l
in the driver's door¢ fig. 30. The light in the
button w ill turn on.
• To deactivate the child safety lock for the
left/right rear door , press the left/right but­
ton [!] in the driver's door. The light in the
button turns off.
The following features are switched off:
- The interior door handles in the rear doors,
- The power windows in the rear doors .
In order to activate the ch ild safety lock on
the left and the right side , press the two safe­
ty buttons
[!l in succession .
Power windows
Controls
The driver can control all power windows.
Fig . 31 Sectio n of t he dr iv er 's d oor: Control s
Opening and closing 39
All power window switches are prov ided with
a two-po sition function :
Opening the windows
• Press the switch to the first stop and hold it
until the window reaches the desired posi­
tion.
• Press the switch briefly to the
second stop
to automatically open the window.
Closing the windows
• Pull the switch to the first stop and hold it
until the window reaches the desired posi­
tion.
• Pull the switch briefly to the
second stop to
automatically close the window.
Power window switches
@ Driver's door
® Passenger's door
© Left rear door
@ Right rear door
& WARNING
-When you leave your vehicle -even if on ­
ly briefly -always take the ignition key
with you . This applies particularly when
children remain in the vehicle. Otherwise
the children could start the engine or op­
erate electrical equipment (e .g . power
windows). The power windows are func­
tional until the driver's door or passeng­
er's door has been opened.
- Be careful when clos ing the w indows .
Check to see that no one is in the way, or
serious injury could result!
- When locking the vehicle from outside,
the vehicle must be unoccupied since the
windows can no longer be opened in an
emergency.
(D Tips
After the ignition has been switched off,
the windows can still be opened or closed
for about 10 minu tes. The power windows
are not switched off until the driver's door
or passenger's door has been opened.

80 On the road
lever position and take your foot off the brake
pedal.
If you select the R position during a Stop
phase, the engine will start again.
Shift from
D to P quickly to prevent the engine
from starting unintentionally when shifting
through
R.
You can determine for yourself if the engine
will stop or not by reducing or increasing the
amount of force you use to press the brake
pedal. For example, if you only lightly press
on the brake pedal in stop-and and-go traffic
or when turning, the engine will not switch off
when the vehicle is stationary. As soon as you
press the brake down harder, the engine will
switch off.
General information
App lies to vehicles: with Start-Stop-System
The standard Start-Stop-mode can be cancel­
led for different system-related reasons.
Fig . 81 Instrument cluster: engine -Stop tempo rarily
unava ilable
Engine will not switch off
Before each stop phase, the system checks if
certain conditions have been met. For exam·
ple, the engine will
not be switched off in the
following situations:
- The engine has not reached the minimum
required temperature for Start-Stop-mode.
- The interior temperature selected by the A/C
system has not been reached.
- The outside temperature is extremely high/
low .
- The windshield is being defrosted
¢ page 69, ¢ page 71.
-The parking system* is switched on.
- The battery charge level is too low.
- The steering wheel is sharply turned or
there is a steering movement.
- After engaging the reverse gear .
- On sharp inclines.
The
fjJ indicator light appears in the informa­
tion line in the instrument cluster display
¢fig . 81.
Engine automatically restarts
The stop phase is interrupted in the following
situations, for example. The engine restarts
without any action by the driver.
- The interior temperature varies from the
temperature selected in the A/C system.
- The windshield is being defrosted
c:!;> page 69, ¢ page 71.
-The brake pedal is pressed several times in a
row.
- The battery charge level becomes too low.
- High power consumption.
Switching the ignition off automatically
To prevent the battery from draining, the igni­
tion will switch off
automatically when all of
the following conditions have been met :
- The vehicle has already been driven.
- The engine has been turned off by the Start-
Stop-System*.
- The driver's door is opened.
- The driver's seat belt is removed .
- The brake pedal is not pressed down.
- The vehicle is stationary.
In this case, the activated low beam will be re­
placed by the side marker lights. The side
marker lights will switch off after approxi­
mately
30 minutes or when you lock the vehi­
cle.
If the Start-Stop System has
not turned off
the engine or if you have switched the Start­
Stop system off manually, the ignition will
not
be automatically switched off and the engine
will continue to run
c:!;> ,&. .,..

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Intelligent technology 195
Switching on and off
ESC turns on automatically when you start the engine.
Fig. 178 Center console,:, OFF button
ESC levels
Sport mode on
The following situations are exceptions where it may be useful to switch on sport mode to
allow the wheels to spin:
- Rocking the vehicle to free it when it is stuck
- Driving in deep snow or on loose ground
- Dr iv ing with snow chains
Sport mode off
Behavior
The ESC and ASR stabilization functions The fu ll stab ilizat ion function of the ESC
are limited¢ ,&.
Operation Press the I~ OFFI button .
Indicator II turns on.
lights
Driver mes- Stabilization control (ESC): Sport
sages Warning! Reduced stability
A WARNING
You should only switch sport mode on if
your dr iving abilities and road conditions
permit.
- The stabilization function is limited
when sport mode is sw itched on . The
dr iv ing wheels could spin and the vehicle
cou ld swerve, especially on slick or slip­
pery road surfaces.
@ Tips
Sport mode cannot be switched o n when
adapt ive cru ise control* is sw itched on.
Braking
General information
What affects braking efficiency?
-
Operating conditions and driving habits
The brakes on today's automobiles are st ill
subject to wear, depending largely on operat­
in g conditions and driv in g habits ¢.&,. . On and
ASR is available again.
Press the
I S'} OFF I button again.
Iii turns off.
Stabilization control (ESC): On
vehicles that are either driven mostly in stop­
and-go city traffic or are driven hard, the
brake pads should be checked by your author­
ized Audi dealer more often than specified in
t he
Warranty & Maintenance booklet . Failure
to have your brake pads inspected can result
in reduced brake performance .
On steep slopes, you should use the braking
effect of the engine. This way, you prevent un­
necessary wear on the brake system. If you
must use your brakes, do not hold the brakes
down cont inuous ly. Pump the brakes at inter­
vals.
Moisture or road salt
Under certain cond itions, for example, when
driving through water or very heavy rain, or
even after washing your veh icle, the braking
effect can be reduced due to moisture (or in
freezing conditions ice) on the brake pads. A
few careful brake applications should dry off
the brake pads or remov e any ice coatings. .,._

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@ Tips
The consumption estimates as published by ENVIRONMENTAL PROTECTION AGENCY (EPA) and Transport Canada may not corre­
spond to your actual consumption on the
road, wh ich will vary depend ing upon vehi­
cle load and speed, road and weather con­
ditions, tr ip length, etc.
Drive smoothly and keep a lookout
ahead
Vehicles use the most fuel when they are ac­
celerating.
~ Avoid unnecessary accelerating and braking.
Vehicles use the most fuel when they are ac­
celerating . If you anticipate what is go ing to
h appen next, you will need to brake less and,
thus , accelerate less . Let the vehicle coast
wheneve r poss ible -fo r example when you see
that the nex t traffic light is red.
Avoid full throttle
Driving at moderate speeds saves fuel and
improves your mileage.
~ T ry and keep well below your car's max imum
speed.
Accelerating gent ly reduces fuel consump­
tion, engine wear, and does not disturb the
environment .
Fuel consumption, exhaust emissions and en­
g ine no ise increase d ispropo rtionately at high
speeds . If you dr ive at approximately three
quarters of top speed, fue l consumption will
be red uced by one ha lf. Never dr ive faste r
than the posted speed limit and wea ther con­
d itions permit.
Reducing unnecessary idling
E ven when your car is just idling it burns up
fuel .
~ Shut the engine off when you are not dr iv ing
the vehi cle.
Dri vin g and en vironm ent 203
~ Do not warm up the vehicle by lett ing the
engine run at id le .
T he id ling phase is au toma tic ally red uced for
vehicles with the Start -Stop -System . It is eff i­
cient to switch off the engine in vehicles with­
out the Start-Stop-System when stopp ed at
railroad crossings and long red lights. Turning
the engine off for jus t 30-40 seconds saves
more fuel than is burned by start ing the en-
. . gme again .
It takes a long t ime for the engine to warm up
fully when it is run ning at id le. However, wear
and noxious emissions are especia lly high
when the engine is warm ing up . So you should
dr ive away as soon as you start the engine and
avo id running at high rpms whi le the engine is
sti ll warming up.
(L} Note
Do not leave eng ine idling unattended af­
ter start ing .
If wa rni ng lights sho uld come
on to indicate improper ope ration, t hey
wo uld go unheeded . Extended idlin g also
produces heat, wh ich could res ult in ove r­
heating or other damage to the veh icle or
other p roperty .
Regular maintenance
A badly tuned engine unnecessarily wastes a
lot of fuel.
~ Have your ve hicle servi ced at reg ular i nter-
vals .
By havi ng your ve hicle regu la rly se rviced by an
Audi dealer he lps to ensu re tha t it ru ns prop­
erly and economically . The condition of your
vehicle not on ly affects its safety and ability to
ho ld its va lue, it a lso affects
fuel consump­
tion .
Check your oil e ach time you fill your tank.
T he amou nt of oi l used is re lated to engine
load and speed.
It is normal for the oil consumption of a new
engine to reac h its lowest value after a certa in
mileage has been d riven . .,..
•
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Trailer towing Driving with a trailer
General information
Your Audi was designed primarily for passen­
ger transportation .
If you plan to tow a tra iler, p lease remember
that the addit ional load will affect durab ility,
economy and performance .
Trailer towing not on ly places more stress on
the vehicle, it also calls for more concentra­
tion from the driver.
F or this reason, a lways fo llow the operating
and driving instructions provided and use
common sense.
(D Note
If you are going to tow a trai le r, you must
ac tivate the trailer operation mode
c::> page 205, Operating instructions.
Technical requirements
Trailer hitch
Use a weig ht-carrying hitch conforming to the
gross trailer we ight. The hitch must be suita­
b le for your veh icle and trailer and must be
mounted secure ly on t he ve hicle's chassis at a
technically sound location . Use only a trail er
hi tch w ith a removab le ball moun t. A lways
check wi th t he tra ile r hi tch man ufactur er to
make sure that you are using the cor rect
h itch.
Do not us e a bumper hitch.
The hitc h m ust be installed in such a way that
i t does not interfe re with the impac t-absorb­
i ng bumper syst em. No mod ificat ions should
b e made to the vehi cle e xhaus t and br ake sys­
tems . From t ime to time, check th at a ll hitc h
mo unt ing bo lts rem ain securely fas tened.
When you are not towing a trail er, remove the
tra ile r hi tch ball moun t. T h is prevents the
hi tch from causing damage sho uld your ve hi­
cle be str uck from behind~ .& .
Trailer towin g 205
Trailer brakes
If your trailer is equippe d wi th a bra king sys­
tem, check to be s ure that i t conforms to all
regulations .
T he trailer hyd ra u lic bra ke sys tem mus t not be
d irec tly connec ted to the vehicle's hydraulic
brake system .
Safety chains
Always use safety chains be tween your ve hicle
and t he tra ile r.
Trailer lights
Trai ler lights must meet all reg ulations. Be
su re to c heck with your Audi dea ler for correct
wir ing, switches and relays .
Mirrors
If you a re unable to see the traffic behind you
u sing the regula r outside mirrors, then you
must insta ll extended mir rors. It is important
t h at you
always have clea r vis io n to the rear.
_&. WARNING
-
Afte r removi ng the t railer hitch , do no t
stor e it in yo ur v ehicl e. In case of sudden
b raki ng, the hi tch co ul d fly forwar d and in­
j ur e you o r yo ur pass enge rs.
Operating instructions
Maximum trailer weight
A tra ile r fo r you r vehi cle is l imited to a typi cal
cla ss 1 o r class 2 tr ailer.
Trailer load distribution
Be sure the load in the tra ile r is held secure ly
in place to p revent it from shift ing fo rward,
ba ckward or sideways.
Never allow a passenger to ride in a trailer
c::> .& in Driving instructions on page 207 .
Eng ine cooling sy stem
Towing a t railer ma kes the engine wor k hard­
er . It is impo rtant that the cooling system's
performance is up to the additional load.
•
•

222 Checking and filling
Checking and filling Engine hood
Releasing the engine hood
The engine hood is released from inside the
vehicle .
Fig. 186 Driver foo twell: release lever
Fig. 187 Rocker switch un der the hood
Make sure the wiper arms are not raised up
from the windshield. Otherwise the paint
could be damaged .
.,. With the driver's door open, pull the lever
under the instrument panel in the direction
of the arrow ¢
fig. 186.
... Raise the hood slightly¢.&_ .
... Pr ess the rocker switch under the hood up­
ward ~
fig. 187. This releases the catch.
.,. Open the hood.
A WARNING
Hot engine coolant can burn you.
- To reduce the risk of being burned, never
open the hood if you see or hear steam
or coolant escaping from the engine
compartment . Wait until no steam or
coolant can be seen or heard before care­
fully opening the hood .
' Working in the engine compartment
Be especially careful whenever you work in
the engine compartment.
Whenever you must perform any work in the
engine compartment, for example checking
and filling different fluids, there is a risk of injury, burns and accidents. To prevent per­
sonal injury always observe the following
WARNINGS. The engine compartment of any
vehicle is a hazardous area
¢ ,&. .
A WARNING
To help avoid injury, before you check any­
thing under the hood:
- Turn off the engine.
- Switch off the ignition .
- Apply the parking brake.
- Move selector lever to P (Park).
- Always let the engine cool down. Hot
components will burn skin on contact.
- To reduce the risk of being burned, never
open the hood if you see or hear steam
or coolant escaping from the engine
compartment. Wait until no steam or
coolant can be seen or heard before care­
fully opening the hood.
- Keep children away from the engine com­
partment.
- Never spill fluids on hot engine compo­
nents . They can cause a fire .
- Never touch the radiator fan. The auxili­
ary electric fan is temperature controlled
and can switch on suddenly .
- Never open the coolant reservoir cap
when the engine is still warm . The cool­
ant system is pressurized and hot cool­
ant could spray out.
- Protect your face, hands and arm from
steam or hot engine coolant by placing a
thick rag over the cap when you open the
coolant reservoir.
- Do not remove the engine cover under
any circumstances. This increases the
risk of burns.
- If work on the fuel system or the electri-
cal system is necessary: ..,_

224 Checking and filling
Engine compartment
Engine compartment overview
These are the most important items that you can check.
Fig. 188 Typ ical layout for contai ners and eng ine o il filler cap
(D Jump start point(-) with hex
head screw .... ............. 234, 283
@ Jump start point(+) under a cov-
er .. .. ............... .... . 234,283
@ Brake fluid reservoir ((0)) . . . . . 231
© Engine oil filler cap ( ®
® Coolant expansion tank (-L) ... 228
Windshield/headlight washer
. (' " ) container O ............ . . 235
The engine oil filler neck (item @) may be lo­
cated in a different area depending on the ver­
sion of the engine.
~ WARNING
Before you check anything in the engine
compartment, always read and heed all
WARNINGS
¢ &. in Working in the engine
compartment on page 222.
-
Engine oil
Engine oil specifications
The engine oil used must conform to exact
specifications.
The service interval display in the instrument
cluster of your vehicle will inform you when it
is time for an oil change. We recommend that
you have your oil changed by an authorized Audi Serv ice Advisor.
If you have to top
off the oil between oi l
changes, use the Audi oil quality standard
specified in the table.
Audi oil quality standard
Gasoline
VW 502 00 or
engine vw 504 00
Diesel vw 507 00
engine

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Using the proper engine oil is important for
the functionality and service life of the en­
gine. Your engine was factory -filled with a
high-quality oil which can usually be used
t h roughout the entire year.
Your Limited New Vehicle Warranty does not cover damage or malfunctions due to
failure to follow recommended mainte­
nance and use requirements as set forth in
the Audi Owner's Manual and Warranty
&
Maintenance booklet .
- Use only a high quality engine oil that ex­
pressly complies with the Audi oil quality
standard specified for your vehicle's en­
gine . Using any other oil can cause seri­
ous engine damage.
- Do not mix any lubricants or other addi­
tives into the engine oil. Doing so can
cause engine damage.
If you need to add oil and there is none
available that meets the Audi oil quality
standard your engine requires, you may
add a total of no more than 0.5 quart/liter
of a high-quality "synthetic"oil that meets
the following specifications.
- Vehicles with gasoline engine: ACEA A3
or API SM with a viscosity grade of
SAE 0W-30, SAE SW-30 or SA E SW-40.
- Vehicles with diesel engine: ACEA C3 or
API CF with a viscosity grade of
SAE 0W-30 or SAE SW-30.
- For more information about engine oil
that has been approved for your vehicle, please contact either your authori zed
Audi dealer or Audi Customer Relations
at 1 (800) 822 -2834 or visit our web site
at www.audiusa.com or
www.audicanada .ca.
Checking and filling 225
Engine oil consumption
T he engine in your vehicle depends on an ade­
quate amount of oil to lubricate and cool all
of its moving parts .
In order to provide effec tive lubrication and
cooling of internal engine components, all in ­
ternal combustion engines consume a certain
amount of oil. Oil consumption varies from engine to engine and may change significantly
over the life of the engine. Typically, engines
with a specified break-in period (see
c::> page 200) consume more oil during the
break-in period than they consume after oil
consumption has stabili zed.
Under normal conditions , the rate of oil con­
sumption depends on the quality and viscosity
of the oil, the RPM (revolutions per minute) at
which the engine is operated, the ambient
temperature and road condi tions. Further fac­
tors are the amount of oil dilution from water
condensation or fuel residue and the oxida­
tion level of the oil. As any engine is subject to
wear as mileage builds up, the oil consump­
tion may increase over time until replacement
of worn components may become necessary.
With all these variables coming into play, no
standard rate of oil consumption can be es ­
tablished or specified . There is no alternative
to regular and frequent checking of the oil lev­
el , see
Note.
If the yellow engine oil level warning symbol
in the instrument cluster
II lights up, you
should check the oil level as soon as possible
c::> page 226. Top off the oil at your earliest
convenience
c::> page 226.
A WARNING
--
Before you check anything in the engine
compartment, always read and heed all
WARNINGS
c::> & in Working in the engine
compartment on page 222.
(D Note
Driving with an insufficient oil level is like-
ly to cause severe damage to the engine. .,.
•
•

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Before you check anything in the engine com­
partment,
al ways r ead and heed all W ARN­
ING S r=;, A in Working in the engine compart­
ment on page 222.
.. Park your vehicle on a level surface.
.. Switch
off the ignition .
.. Read the eng ine coolant leve l from the cool­
ant expansion tank¢
fig. 191, ¢ page 224,
fig. 188.
With a cold engine, the coolant
level should be between the "min" and
"max" markings. When the engine is warm,
the leve l may be slightly above the "max"
mark ing .
The location of the coolant expans ion tank
can be seen in the engine compartment illus­
tration ¢
page 224.
To obta in an accurate read ing, the engine
must be switched
off.
The expansion tank in your vehicle is equipped
with an electric coolant level sensor.
When the coo lant level is too low, the warning
light in the Auto-Check System
¢ page 16 will
illum inate until yo u add coolant and the level
has been restored to normal. Even though
there is an electric coo lant level sensor, we
still recommend you check the coolant leve l
from time to time .
Coolant loss
Coolant loss may indicate a lea k in the cooling
system. In the event of coolant loss, the cool­
ing system should be inspected immediately
by your authorized Audi dealer . It is not
enough merely to add coola nt.
In a
sealed system, losses can occur only if
the boiling point of the coolant is exceeded as
a result of overheat ing .
A WARNING
The coo ling system is unde r pressure and
c an get ve ry ho t. Reduce the risk of s cald­
ing from h ot coolan t by followi ng these
steps .
- T urn
off the engine and allow it to coo l
down.
Checkin g and fillin g 229
-Protect your face, hands and arms from
escaping flu id and steam by covering the
cap with a large, th ick rag.
- Turn the cap slowly and very carefully in
a counter-clockwise d irect ion while ap­
plying lig ht, downward pressure on the
top of the cap .
- To avo id being burned, do not sp ill anti­
freeze or coolant on the exhaust system
or hot engine parts. Under certa in cond i­
tions, th e ethylene glycol in engine coo l­
ant can catch fire.
(D Note
Do not add any type of radiator leak sea l­
ant to your ve hicle's engine coolant. Add-
i ng radiator repa ir flui d may adverse ly af­
fe ct the funct ion a nd pe rfo rma nce of you r
co oling system and could re sult in damage
not covered by your New Vehicle Limi ted
War ranty.
Adding coolant
Be very careful when adding engine coolant.
Before you ch eck anyth ing in the eng ine com­
partment,
alway s re ad and heed all WARN­
INGS ¢ A in Working in the engine compar t­
ment on page 222.
.. Requirement: The re must be a residua l
amount of coolan t in the expansion ta nk
¢(D .
.. Tu rn off the engine.
.. Let the engine cool down.
.. Place a thick rag ove r th e coo lant expansion
tank
¢ page 228, fig . 191 and carefully
twist the cap counte r-clockwise ¢.&, .
.. Add coo lant m ixed in the correct ratio
¢
page 228, Coolant up to the MAX mark ­
ing .
.. Make s ure that the flu id leve l remains sta-
b le. Add more coo lant if ne cessary.
.. Twis t the cap o n again
t ightly.
Replacement engine coo lant must confo rm to
exact spec ificat ions
r=;, page 228, Coolant. ..,.
•
•

230 Check ing and filling
We recommend using on ly coo lant addi-
tive
Gl2++, Gl3 or in an emergency Gl2 +. Do
not use a different additive . In an emergency
use plain water unt il you can get the correct
additive and can restore the correct ratio. This
should be done as soon as possible .
If you have lost a cons iderable amount of
coolant, then you should add co ld antifree ze
and cold water only when the engine is co ld.
A lways use
new engine coolant when refilling.
Do not fill coolant above the "MAX" mark. Ex­
cess coolan t will be forced out through the
p ressure relie f valve in the cap when the en ­
gine becomes hot.
A WARNING
- The coo ling system is under press ure and
can get very hot. Reduce the risk of
sca lding from hot coolant by following
these steps.
- Turn off the eng ine and a llow it to cool
down.
- Protect your face, han ds and arms from
escap ing fl uid and steam by cover ing
the cap with a large, thick rag.
- Tur n the cap slowly and very c arefully
in a counter-clockwise d irect ion while
applying light, downward press ure on
the top of the cap .
- To avo id being burned, do not sp ill an ­
tifreeze or coolant on the exhaust sys ­
tem or hot engine parts. Under certain
conditions, the ethylene glyco l in en­
g ine coolant can catch fire.
- Antifreeze is poisonous. Always store an­
t ifreeze in its or iginal container and well
out of the reach of children.
- If you drain the coolant, it must be
caught and safely stored in a proper con­
tainer clear ly marked "poison".
- Do not add coolant if the expansion tank
is empty. A ir could enter the cooling sys­
tem and damage the eng ine. If this is the case, do not cont
inue driving . Seek
professiona l assistance .
- Coo lant poll utes the environmen t and
co uld cause an engine fire . Excess cool­
ant will be forced out thro ugh the pres­
sure relief valve in the cap when the en­
gine becomes hot.
- If, in an eme rgency, only wate r can be
added, the correct ratio between water
and antifreeze
c::> page 228 must be re­
stored as soon as possible .
@ For the sake of the environment
Drained coolant should not be reused . A l­
ways d ispose of used coolant while observ­
i ng all environmental regulations .
Radiator fan
The radiator fan switches on automatically by
itself.
An a uxiliary electric radiator fan switches on
and off depending on coolant temperature
and other vehicle operat ing condit ions .
After yo u switch the engine off, the auxi liary
fan can continue r unning for up to 10 minutes
- even w ith the ignition off . It can even switc h
on again later by itself
c::> .& , if
- the temperature of the engine coo la nt rises
due to the heat build- up from the engine in
the engine compartment, or
- the engine compa rtment heats up because
the vehicle is parked in intense sunlight.
A WARNING
- To reduce the risk of personal injury nev­
er touch the radiator fan.
- The a uxiliary electric fan is temperat ure
controlled and can sw itch on suddenly
even when the engine is not ru nning .
- The a uxiliary radiator fan sw itches on a u­
tomatically when the engine coo lant
reaches a certai n temperature and will
continue to run until the coolant temper­
ature drops.