Ford Focus RS (2011 year). Manual - part 116

• Seals must be correctly installed. Special

attention must be paid at corners -arrow- that
the installation follows the contours.

• The seal must not show any kinks or folds or

any other damage.

• Seals must seal all around their circumference.

Gaps in seals result in openings which lead to
an increased incidence of noise. In this respect,
it is especially important to pay attention to the
seals in the area of the windows.

Remedial Action

Renew older seals which no longer have adequate
preload. Deformed or widened retaining flanges
must be reworked and provided with a new seal.

The corner areas -arrow- of a seal must be
properly seated. In some circumstances, a butyl
sealing strip must be affixed to support the sealing
at a corner.

Bonded joints

Glass is usually installed today using a bonded
joint. Gaps in the bonded joint can lead to noises
in the vehicle interior. If there are noises which are
believed to be associated with window glass, the
following points should be checked:

Gap in window bonding

• The window must be bonded without any gaps

-arrow-. Leaks can be found using the ultrasonic
tester or compressed air carefully blown from
inside onto the window glass bonding.

• The installed position of the window glass must

be correct. It must not have been bonded into
a position which is too low or offset to one side.

• The sealing or trim strips must fit tightly and the

glass must be mounted so that it is fully
enclosed. If a sealing or trim strip has not been
applied with enough pressure, high air speeds
can cause it to lift up. This can lead to wind
noises at higher speeds. Apply masking tape to
these areas for test purposes.

Corrective measures

Leaking areas of the window glass bonding
material can be sealed using PU sealing
compound. Pay special attention at the front
windshield, that any breaks in the bonding are not
too large. Otherwise the glass must be removed
and bonded in place again.

The installed location of a window glass cannot be
corrected. It must be removed and bonded into
place again.

Replace the trim strips or secure the lip seal using
PU adhesive.

Gaps, edges

Door gaps and edges are places where air
turbulence can form. This causes noises which can
be perceived as troublesome.

Gaps and edges - problem areas

Doors, hood and tailgate can cause wind noises
because of gaps -arrow- which are too large. If the
components are not installed flush to the bodywork
or the neighboring component, air break edges can
arise, which in turn can create a wind noise.

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The sun roof may be the cause of whistling noises
in the roof area. The sun roof may be incorrectly
adjusted or the seal on the sun roof may be
damaged.

Noises from the door area could come from a
window which does not fully close. Side guides
(seals) can also be the cause of wind noises.

The covers of window frames can be incorrectly
mounted or aligned. The quarter-lights in doors
must also be checked for correct installation.

Corrective measures

Check the gaps and adjust them according to the
specifications. If there are problems at the sun roof,
correct the adjustment and if necessary replace
the seals.

Problem area at side windows

Side windows which do not fully shut -arrows- must
be adjusted. If the vehicle is equipped with electric
window regulators, the remedy may be to perform
the window regulator learning process again. In all
cases, make certain that the glass enters far
enough into the seal.

Ancillary Components

Components installed on the bodywork may cause
noises when they are not correctly mounted.

When troubleshooting it may be helpful to remove
the suspected component or, when this is not
possible, to mask it off with suitable covering tape.

Roof moldings, roof rail, roof antennas

Moldings and roof moldings must touch the
bodywork along their whole length without any gap.
Check the end sections in particular. These must
neither have any splits nor stand away from the
bodywork.

Noises may come from the roof rail if the seal
between it and the roof is not correctly installed or
is cracked. Gaps at the mounting grooves of the
carrier can also create wind noises.

The roof antenna and antenna foot seal must be
correctly secured. The seal must lie completely on
the roof and must not be damaged.

Roof moldings mounting

If the original mounting points of the roof moldings
are in good condition, the fixing can be improved
using silicone sealant -arrow- if necessary. Align
or renew the seals of the roof rail. Reduce the
clearances of the mounting grooves.

Corrective measures

If the original mounting points of the roof moldings
are in good condition, the fixing can be improved
if necessary using silicone sealant -arrow-.

Exterior mirrors

Exterior mirrors or covers of exterior mirrors which
are not correctly mounted cause noises. The cover
must lie evenly on the component and must not lift
during driving. There are ducts present on the
doors for the electrical or mechanical adjusters for
the exterior mirrors. If there are leaks, wind noises
will be caused. Holes can also be present at the
transition to other components.

Exterior mirror seals

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There are ducts present on the doors for the
electrical or mechanical adjusters for the exterior
mirrors. If there are leaks, wind noises will be
caused. Holes can also be present at the transition
to other components.

Remedial Action

If there is inadequate sealing of the foam seals -2-
they must be replaced or supplemented with
suitable material. Transitions to other components
can be sealed with butyl sealing compound -1-.

Moldings, covers, door handles, windshield
wiper arms

Moldings and covers especially tend to cause wind
noises because of their location. These
components interrupt smooth bodywork surfaces
and air turbulence therefore arises at the edges.
If there are noise concerns in the area of the doors,
check especially for gaps and projections. Moldings
must not stand away from the bodywork or the
door. There must not be any gaps or discontinuities
at the location of joints.

Incorrectly adjusted windshield wiper arms can
cause wind noises. Especially if they are too far
over the glass surface when in the rest position.

Wind noises in the transition area between the air
cowl cover and the wing or the windshield can be
caused by an incorrectly installed air cowl cover.
At high air speeds the air cowl cover may lift and
noises will then occur.

Because of their necessary mechanical features,
door handles have a range of openings and edges
which allow noise to be generated. The door handle
can be masked off for testing purposes. If a
reduction in wind noises is noticed, inadequate
sealing may be the reason for the noises.

Remedial Action

Openings which are used to secure trim panels
must be checked for leaks. Any leaks found can
be rectified using butyl strips.

Loose or damaged outer trim on the pillars -arrow-
must be secured or replaced.

A butyl sealing strip -1- can be laid underneath the
cover in the transition area between the air cowl
cover and the wing or windshield.

The sealing of the door handles must be renewed
when required. In addition, noise absorbing
material can be applied to the back of the door
handles.

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Noise, Vibration and Harshness

Noise, coming from the vehicle and which can be
heard inside and outside the vehicle.

Vibrations, oscillations that are felt and noticeable
inside the vehicle.

Harshness, noises which come from the vehicle
and which can be heard, felt and noticed inside
and outside the vehicle.

These terms are grouped together under the title
Noise, Vibration, Harshness, or NVH for short.

The task of vehicle development and production
is to ensure that noises caused by the vehicle do
not disturb the driver and passengers. Moreover,
the the external noises emitted by the vehicle must
not exceed the thresholds set by law.

NOTE: Basic and advanced training courses are
offered for the following contents. For an overview
of all courses offered, please

refer to the Ford

Service Organisation's training

course brochure.

Noise types and causes

Noises in and around the vehicle are assigned
specific descriptions:

• Humming and droning are perceived as low

tones.

• Buzzing and whirring are middle tones.

• Howling, whistling, squeaking are assigned to

the high tones.

Low to middle tones are considered to be
unpleasant. They are palpable and noticeable as
oscillations and vibrations throughout the body.
Loud howling and whistling is painful to the ears.

A noise usually consists of a superimposition of
different tones which spread as oscillations.

Each of these oscillations has a specific oscillating
time and can be measured in frequencies. The
frequency describes the number of oscillations per
second. The frequency unit is specified in Hertz
(Hz).

The human ear can perceive frequencies between
20 and 20000 Hz.

Where the different notes come from in a
vehicle:

• Low notes are mostly produced by the engine.

• Low tones can also be produced by the

roadbed, particularly on rough surfaces. This is
a form of droning which can be felt by the
vehicle occupants as vibration or roughness.

• High tones however, which are experienced as

howling or whistling noises, are often air
currents (wind noises) or come from ancillary
components such as the generator, power
steering pump or drivebelt.

• There are also clattering noises which can occur

when driving over an uneven road. These
jerking noises are produced by, for example,
the shock absorbers, chassis components or
loose articles inside the vehicle.

Noises can already be contained where they occur
or, if this is not possible, can be confined with
suitable measures.

The basic procedures here are the damping of
oscillating parts, the insulation of components or
the absorption of the noises through appropriate
materials.

Damping

If a damper is installed next to an oscillating mass,
the characteristic of the damper will reduce the
movement of this mass accordingly (e.g. bumper
on chassis).

Damping affects the resonance of an object or
system.

Isolation

In oscillation technology, the term isolation means
decoupling (separation) of components and
systems. An engine is mounted in sprung elements,
so that as little oscillation as possible is passed to
the vehicle.

In automotive technology, the isolation technique
used is nearly always rubber mounting. Rubber
has a large internal damping capacity. The
elasticity of the rubber acts like a spring.

Absorption

Sound waves are reflected from hard surfaces
Through the use of absorption material, sound
waves hit soft surfaces and are absorbed by them.

The composition and thickness of the material used
plays an important role here. A soft surface,
depending on its composition, absorbs the sound
waves and reduces their energy.

NVH elements

NVH elements are installed to prevent airborne
sound transfers to the passenger compartment in
different body cavities.

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Description

Item

C-pillar area

B-pillar area

A-pillar area

On the Focus 2004.75 (07/2004-) these elements
are located in the cavities of the A, B and C pillars.
On the estate version, they are also located in the
D pillars.

The NVH material consists of a carrier plate which
has compressed isolation material at the edges.
In the drying system of the painting equipment used
in production, the body is heated to approx. 170°

C. At this temperature the isolation material
expands to seal the gap between the carrier plate
and the bodywork.

NOTE: NVH elements must not be damaged during
work on the vehicle body. NVH elements deformed
through impact must always be replaced. PU
adhesive must always be applied to the edges of
new and reused NVH elements during repair work.

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Description

Item

NVH element

PU adhesive

For the exact installation position of an NVH
element, please

refer to the vehicle-specific repair

instructions.

If an NVH element is to be reused, the bonding on
the body panel must be detached. To do this, the
body panel must be heated in the area around the
NVH element. The bonding can be detached at
approx. 170° C. The damaged panel part can now
be carefully dismantled.

Before installing the new panel part, a PU adhesive
must be applied to the contact areas between the
panel and the NVH element.

Test techniques, measuring devices

The shortest route to an accurate diagnosis results
from:

• general information on the problem vehicle and

a comparison test with a vehicle of the same
construction, without NVH problems.

• vehicle history, including repair history and

usage patterns.

• condition history, especially any relationship to

repairs or sudden change.

• knowledge of probable causes.

• application of diagnosis procedures in which the

vehicle is split into corresponding areas.

The diagnosis and correction of noise, vibration
and harshness concerns requires:

• general information on the problem vehicle and

a comparison test with a vehicle of the same
construction, without NVH problems.

• vehicle history, including repair history and

usage patterns.

• condition history, especially any relationship to

repairs or sudden change.

• knowledge of probable causes.

• application of diagnosis procedures in which the

vehicle is split into corresponding areas.

NOTE: The diagnosis of droning problems is one
of the most difficult tasks in the NVH area. With
the exception of installed components under stress,
a certain diagnosis of droning problems (or boom)
on customer vehicles makes great demands on
the automotive technician. The performance of
measuring equipment and their practice-orientated
application can only be obtained through suitable
instruction (NVH training). The successful use of
these devices requires a great deal of experience
on the part of the user.

The diagnosis and correction of noise, vibration
and harshness concerns requires:

• a road or system test to determine the exact

nature of the concern.

Analysis of possible causes:

• checking of the cause and elimination of the

faults found.

• a road test or system test to make sure the

concern has been corrected or brought back to
within an acceptable range.

• It is often very difficult to locate noises that are

audible in the passenger compartment based
on the problem description provided by the
customer and the road tests performed. The
direction of the noise can be detected
subjectively, but the source of the noise cannot
be found.

NOTE: For a selection of simple test tools, see the
wind noises section.

Electronic NVH tester

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NOTE: Before using the NVH tester in the service,
the service technician should take part in an NVH
training course to ensure effective use of this
device during the road test. A description of the
function and application of the NVH tester is
enclosed with the device.

The measuring device described below is used for
diagnosis of the solid-borne sound and solid-borne
sound transmission paths. The device is particularly
suitable for medium and high frequency noise
analyses. It principally enables noise diagnosis in
the area of solid-borne sound and helps to identify
solid-borne sound transmission routes.

In order to obtain a positive diagnosis of droning
problems (low frequency noises) and their sources,
you must have sufficient experience of how to use
this measuring device.

The device works according to the following
operating principle: Accelerometers (transmitters)
are fitted on various vehicle components or body
areas. The signals recorded here can be listened
to one after the other on headphones or speakers
via the different channels. Simultaneous illustration
of several or all measuring channels (for
comparison) is only possible visually on the display
of the measuring device.

Layout and operation:

• The test device has six different channels for

noise diagnosis.

• Each channel is marked in color on the terminal,

cable and test device.

• The solid-borne sound recorded is transmitted

to the test device or the headphones by the
magnetic accelerometers (transmitters).

• There is an amplifier on the test device with

which the signal strength and the corresponding
channel can be set.

• Only the noises from a transmitter are

transferred to the headphones.

• All connected cables can be visually illustrated

individually or simultaneously on the display.

• The test device saves the recorded data.

• The recorded data can be imported to a PC and

evaluated.

The NVH tester is equipped in addition with mobile
magnetic sensors which are particularly suitable
for the following noise tests:

• Internal noises at the dashboard

• Engine noise

• Electrical noises (sparking/voltage

transmissions)

• Wind noises

• Vacuum - leaks

Chassis noise tester (chassis ear)

Used to diagnose solid-borne sound and its
transmission routes. The device is particularly
suitable for medium and high frequency noise
analysis and principally enables noise diagnosis
in the area of solid-borne sound and helps to
identify solid-borne sound transmission routes.

In order to obtain a positive diagnosis of droning
problems (low frequency noises) and their sources,
you must have sufficient experience of how to use
this measuring device.

Layout and operation:

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The test device has six different channels for noise
diagnosis. This means that six microphones
equipped with clamps can be attached to different
components on the vehicle. The emitted or
transmitted solid-borne sound will be transferred
from microphone to the headphones. There is an
amplifier between the microphone and the
headphones at which the signal strengths and the
corresponding channel can be set.

Only the noises from one microphone are
transferred to the headphones. Each channel is
color-coded on the clamp, cable and amplifier.

NOTE: In order to be able to relate the positions
of the different microphones during the test
process, they are entered in a special test sheet
according to their colors. Microphones, clamps and
cables must be carefully routed and attached.

Test process (example for transmission noise):

• Attach microphones to various positions on the

transmission or mountings. This first allows the
source of the noise to be determined, and then
the possible transfer routes.

• A road test can be performed after all the

clamps have been attached to the vehicle and
all the cables connected to the amplifier.

• Firstly, all the channels are switched through

one after the other in neutral, to check the
operation of the different channels as well as
the noise level in neutral.

• During the road test, all channels are listened

to in the different gears, engine speeds, vehicle
speeds and loads. This procedural method
permits unambiguous diagnosis of the cause of
the noise and the route of the noise until it
enters the bodywork structure.

• The characteristics of the noise which is the

cause of the concern should match those of the
noise which is heard. This means compare the
sound.

• Depending on the input signal level, there may

be a great deal of difference in the noise level
in the individual channels.

• Always set the amplifier volume to zero before

switching to another channel.

• In order to be able to make any comparisons,

the volume settings of the different channels
must be recorded on the test sheet.

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