Ford Fiesta (2011 year). Manual — part 90

degree of torsional stiffness. This is achieved by
using high, super-high and maximum-strength
sheet steel and body reinforcements in
specifically-targeted areas.

These reinforcements can be installed in the area
of the doors (diagonal braces etc.) or on the
underfloor. In contrast to the saloon (or other
non-convertibles) with square-section side
members (closed profile), these reinforcements
have a profile which is open on the underside
(U-section).

Special constructional changes within the bodywork
structure:

• Reinforcing or increase in the thickness of the

sheet steel in the pillar area.

• Reinforcing or increase in the thickness of the

sheet steel in the floor pan structure (rocker
panel area).

• Use of heavily structured reinforcing panels in

the rocker panel and pillar area.

• In the area of the windshield frame and A-pillars,

thick-walled reinforcing tubes are used (roll-over
protection).

• Because there is no roof, the bridge construction

principle cannot be used as it is on the saloon
for example. Flexural and torsional rigidity must
be ensured by other components.

Non-monocoque bodywork

Non-monocoque bodywork is built onto a frame or
a chassis. Frames used for this have various
construction forms, e.g. the ladder frame or tube
frame. Non-monocoque bodywork is the original
way of constructing vehicles.

Description

Des

cript

ion

Vehicle body.

1

Frame Assembly

2

Bolted connection

3

The ladder frame is still commonly used today for
truck and off-road vehicles. The bodywork is placed
on the frame or chassis. The total load which
occurs while driving is transferred to the chassis.

More sporting vehicles can be built with
non-monocoque bodywork, mostly using a lattice
tube frame. Limitations in the design are accepted
for the benefit of low weight. The outer skin here

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is usually made of plastic or alloy. This type of
construction is also common in touring car racing
for instance.

Special features of non-monocoque bodywork
construction:

• Partly large surface panels and high volume

shaped parts.

• Thicker materials and greater reinforcements

in the frame area.

• Floor pan as frame structure with high torsional

rigidity and flexural strength.

• Side panels only make a small contribution to

the overall stability of the body.

Instructions for repair:

A different repair technique is necessary during
repairs. A deformed frame structure requires high

suction power during straightening repairs.
Frequently, the body also has to be detached from
the frame structure in order to carry out separate
repair.

Due to the very stable frame structure, please note
that the straightening behavior is completely
different to that of a passenger vehicle. The frame
and the attached body must be repaired
independently of each other.

Further information can be found in the respective
body repair manual.

Special points:

Tailored blanks

Blue: Tailored blank

Arrows: Laser weld seam

The term "tailored blanks" describes the connection
of two different panel thicknesses and/or strengths
in the bodywork carcass. This connection is done
using laser weld seams. Cut locations exactly on
the laser weld seams are not permitted, as at
present no joining techniques are approved for use

in repair procedures that would re-create joins of
the same quality.

NOTE: No cutting, no welding and therefore no
sectional repairs are permitted in the immediate
area of the laser weld seams. The model specific
requirements are documented in the respective
Body Repair Manuals.

Typical application areas are:

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• Side member

• Door inner reinforcement/door frames

• Wheelhouses

• Rocker panel inner reinforcement

• Roof rail inner reinforcement

Deformation behavior

Description

Des

cript

ion

Bolted crash element

1

Front side member

2

Rear side member

3

Different materials and design features lead to
staged deformation of the front and rear of the
vehicle in an accident.

Crash element:

At the front of the vehicle there is a crash element
which is connected to the side member by threaded
connections. This crash element can absorb light
impacts of up to about 15 km/hr. Because of the
threaded connections, the crash element can be
changed very quickly.

NOTE: Deformed crash elements must not be
straightened or repaired.

Heavier impacts which can no longer be absorbed
by the crash element must be absorbed by the side
members or the floor pan structure. Depending on
the extent of the damage, a part or complete
replacement can be performed on the side
member.

The rear of the vehicle, like the front of the vehicle,
has structures which protect the passenger cell
through staged deformation in the event of an
accident. The design layouts, however, are adapted
to the requirements of the rear area.

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Diagnosis and Damage Evaluation

Assessment of the extent of the damage includes
visual inspection and dimensional inspection of the
vehicle. In order to correctly determine the extent
of the damage caused by an accident, in-depth
technical knowledge, practical experience with the
technical equipment and the testing and measuring
devices is required.

Noticeable damage to the bodywork
structure

Positive accidental damage assessment can only
be achieved if the service technician is able to
reconstruct the effect of an impact on the body
structure.

For example:

If the impact occurs on the front left-hand side
member, the right-hand side member will usually
also have been damaged. Often the length of this
side member will not have changed, but because
of the rigid body design, it may have become
deformed. This damage can be detected through
the size of the gap between the door and fender
or by measuring the vehicle.

In the case of more severe impacts, in which the
front part of the vehicle cannot absorb all of the
impact energy, the passenger cell is also used to
absorb the energy. Here, the energy is transferred
via the A pillar and distributed there. This results
in deformations in the roof and the door sill.

NOTE: Because of existing damage to the
bodywork structure, damage diagnosis on a vehicle
lift may give extra incorrect diagnosis results.

NOTE: Training courses are offered on this subject.
For an overview, please refer to the Ford Service
Organisation's training course brochure.

If for instance the Ford Focus Coupé/Cabriolet is
raised on a vehicle lift, the dead weight of the
vehicle will cause the front end to drop by approx.
2 to 3 mm.

The altered door position is clearly recognizable
by stiffness of the lock; the door moves upwards.
This causes the lock pin to contact the guide
element of the door lock.

It is possible to draw conclusions about the extent
of the damage through a visual inspection of the
external damage. In general, the following areas
are to be checked during the visual inspection:

• Outer panel including seam seals for cracks or

flakes in the paint caused by the accident.

• Size of the gap on doors and hoods for

evenness.

• Freedom of movement of door and hood/tailgate

locks.

• The vehicle roof for folds (gap measurement on

vehicles with sunroof)

• Dotted flange in door section for deformation

and cracked weld spots.

• The side members and crash components for

crumpling and folding.

• Trunk floor and floor pan from above and below

for crumpling.

No noticeable damage to the bodywork
structure

In addition to external indicators such as flaking
paintwork or cracks in the underbody protection, it
is vital to check for damage to the body structure
that is not visible from the outside (hidden body
damage) during a damage assessment. Unless
ancillary components are removed, it is often
impossible to achieve accurate diagnosis of the
underlying body parts.

NOTE: In order to determine the damage as
accurately as possible, it may be necessary to
remove ancillary components in the area of the
damage.

Particular attention must be paid to the following
components:

• The A, B and C pillars in the roof area.

• Floor pan.

• Rear ancillary components, such as bumper,

lights, etc.

• Trunk floor, spare wheel cavity.

• Rear coverings, such as interior trim, carpet,

etc.

• Lower rubber seals, e.g. in door area (welded

flange).

• Area under the rear seat.

• Attachment points of transmission system,

steering, engine, drive shafts, front and rear
axles.

• Electrical components, e.g. the radio (damage

through shaking or through voltage peaks).

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