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The New Audi A4 Cabriolet: In Depth

An enjoyable and sporty driving experience, superior and complex technology, classic yet exciting styling and a level of luxury that even satisfies the demands made in the luxury class: Audi is presenting the new generation of a car that has become a classic – the A4 Cabriolet.

The advent of a new model generation is evident at first glance: the open-top four-seater now has the single-frame grille that typifies the brand. The newly styled rear lights add a further visual touch. The car’s taut styling, clear surfaces and tension-packed shoulder line extending along the entire body are characteristic features of the A4 Cabriolet.

The car’s technology lives up to the promise made by its new styling: the

A4 Cabriolet is being launched with four engines, three of which are new. FSI and turbo technology represent the most advanced state of the art for petrol engines, as do the ultramodern piezo injectors in the three-litre TDI, for example. The sporty yet comfortable dynamic suspension converts the power delivered by these units into sheer driving pleasure – on every bend, on every mile of the journey.

Innovative and highly sophisticated technologies are an integral part of practically all vehicle areas and components: the optional xenon plus headlights with daytime running lights and dynamic adaptive light technology are proof of this, as are the continuously variable multitronic transmission, which is still unique, and quattro permanent four-wheel drive.

The quality of materials and workmanship in the interior are of a standard that need not fear comparison with the luxury class. The architecture of the driver’s area, especially the cockpit – a perfect synthesis of design, ergonomics and function – is pioneering.

The Design

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The exterior

Unmistakeably Audi: the new generation of the Audi A4 Cabriolet once again exhibits the brand’s typical design features. Their sports character is immediately visible at first glance.

The new styling elements are especially striking. They immediately draw attention at the front of the car: the striking single-frame grille and newly styled clear-glass headlights with their curving, emotional line give the new Audi

A4 Cabriolet a completely new face.

The tubes of the main beam lights catch the eye behind the covers. They form the optical focus of the light units, framed to the side by the orange-coloured round indicator lights. Here, Audi’s design engineers have made technology visible.

The ratio of the large, clearly shaped body surfaces to the flat, equally bold strip formed by the windows is significant. The Cabriolet’s utterly sporty but elegant design captivates the onlooker at very first glance. Clear lines, large surfaces and not a join too many: these are the characteristic features of the new Cabriolet’s timeless elegance. The high, rising shoulder line, which extends along the entire side of the body, additionally enhances the vehicle’s powerful overall impression.

Lights behind clear glass catch the eye at the rear of the car, further emphasising the high-quality appearance of the A4 Cabriolet. The prominent rear diffuser is flanked by two tailpipes.

The Audi A4 Cabriolet always cuts a fine figure – with the top up or down. The electro-hydraulic hood is integrated harmoniously into the vehicle’s overall architecture, without the occupants having to accept any considerable compromises in terms of function.

The Audi A4 Cabriolet remains a genuine four-seater which, thanks to its generously dimensioned luggage compartment, can accommodate four people and their luggage on holiday.

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The interior

On a convertible with the top down, the interior is more an integral part of the exterior design than on any other type of vehicle. It is therefore important for the interior to take up the formal principles of the exterior design. The perfectly tailored suit: in the Audi A4 Cabriolet, two apparent opposites are combined to produce an amazing synthesis of extraordinary ergonomics and subjective well-being.

The lines and surfaces of the new A4 Cabriolet’s cockpit extend far into the region of the door panel and centre console, quite literally seeming to embrace the driver. This “wrap around” effect, to use the designers’ technical term, is accentuated additionally by the A4 Cabriolet’s high, gently rising waistline. This feature is something that many customers value very highly, not least because of the remarkable sense of security that it imparts.

The architecture of the dashboard and centre console also provided the designers with scope for positioning a wide range of instruments and controls high up, ideally within the driver’s field of vision, in other words. This is a basic ergonomic design that is adopted in every aircraft cockpit – and not without reason.

The lines of the driving area create a lively interplay of distinctly rounded, tangible shapes and graphically clear edges and notches. This area is thus divided up into clearly defined zones. These can be distinguished at a glance – a worthwhile ergonomic bonus that speeds up intuitive access to the individual information units and function groups. This process of locating involves both the visual and tactile senses: groups of controls and displays can also be identified by the materials used.

As far as the instruments are concerned, the most important information elements are located under a dome-shaped cover. The dial graphics of the large round instruments dispense with all fashionable gimmicks. Together with the standard central display, the white instrument lighting ensures optimum readability.

The most important controls for the occupants’ well-being are located in the centre console: deluxe automatic air conditioning, the audio system and the optional navigation system plus. The air conditioning controls on left and right are within easy reach of both driver and front passenger.

There are, however, more benefits to the interior design than sheer practicality. The design of the self-contained function zones also creates a basis for a wide range of combination options for materials and colours. From the designers’ viewpoint this opens up entirely new horizons, and for A4 Cabriolet drivers it provides scope for an unprecedented degree of customisation.

The customer’s tastes and imagination are almost unrestricted when it comes to the choice of equipment and trim. The fact that the finish and quality of all fabrics and upholstery materials are of a standard you would expect to find on a luxury car is a fitting reflection of how Audi perceives itself.

Comfort and space on all seats

The micro-engaging mechanism for adjusting the front seats adds a new dimension to finding the ideal seated position which will benefit all occupants, not just the taller ones. Their fore/aft position can be adjusted practically infinitely, in increments of three millimetres.

The seat surface, which is longer than the norm in this vehicle class, provides an outstanding thigh support. This applies in particular to the sports seats which, in addition to an adjustable lumbar support, come with a thigh support that can be adjusted horizontally to suit individual requirements.

The rear seats offer plenty of space, even for tall occupants – which is something that cannot be said of every four-seater convertible.

There is also more room than average for luggage in the Audi A4 Cabriolet: with a capacity of 315 litres with the roof closed, the smooth-floored luggage compartment is also well equipped for large quantities of luggage. The standard load-through hatch with ski bag for four pairs of skis or two snowboards can also be used to transport bulky items.

The body

The body of the new Audi A4 Cabriolet is noted for its very high torsional rigidity, reducing body twist to a minimum. This not only increases safety, but also boosts ride comfort. Additional measures increase rigidity still further: these include tube-reinforced side panels and an extremely rigid and robust windscreen frame. It goes without saying therefore that the new Audi A4 Cabriolet meets the most stringent crash test requirements without any trouble.

Audi is one of the pioneers of lightweight design. On the A4 Cabriolet, various materials such as steel and aluminium have been combined in such a way that it was possible to keep the vehicle weight down without reducing body rigidity and safety. This includes the expansive use of high-strength and very high-strength sheet panels. These special panels are used primarily in the front end of the new A4 Cabriolet, in order to absorb impact energy as effectively as possible in a frontal crash.

As a protective cage, the occupant cell must also make sure that deformations and intrusions are minimised in a crash. Part of this task is performed by three large tailored blanks incorporated into the floor area. The wall thickness of each of these blanks varies. They are joined together by laser weld seams. The advantage of this special technology is that the generally large-format tailored blanks can be structured in such a way that high wall thicknesses are only used in areas subjected to particularly high loads. The result is a highly rigid structure which weighs less.

For the passenger cell, the tailored blanks form a stable, homogeneous bond with the forward and rearward structure via a bifurcated system of support members. Audi’s development engineers optimised profiles, wall thicknesses and material grades in extensive crash simulations.

In the rearward structure, the vehicle’s longitudinal member – which has to absorb much of the impact energy in a rear-end impact – is made using tailored blanks of varying wall thicknesses and materials.

The use of tailored blanks at specific points around the doors also helps to save weight. Energy-absorbing aluminium plates are used in the doors for impact protection.

The hood

The new Audi A4 Cabriolet has a soft top which can now be opened electro-hydraulically at the press of a button in just 21 seconds – an improvement of more than five seconds on its predecessor. As well as aesthetic advantages, especially when the roof is closed, it also offers numerous practical benefits compared with other roof concepts. For example, A4 Cabriolet drivers still have ample space to stow their luggage – even when the hood is open.

The Audi A4 Cabriolet is a car for all seasons, whatever the weather: the soft top is noted for its outstanding acoustic and thermal insulation. The glass rear window is heated and therefore clears quickly in winter.

The electro-hydraulic hood opens fully automatically as a standard feature. It can be opened and closed at the press of a button. The fully automatic hood can be operated when driving up to a speed of 30 km/h. This is a particularly convenient feature, especially in the city where it is not always possible to stop suddenly, or just before parking the car, when approaching the garage, for example.

Audi is setting a new standard for soft tops with its optional acoustic hood. By using new fabrics with a higher material density as well as an additional padded layer around the C-posts, the noise level inside is reduced to a level that scarcely differs from that in the Audi A4 saloon.The new roof also improves the thermal insulation properties. This increases driving pleasure and comfort considerably when driving with the hood up. Audi offers a choice of four colours for the hood; the headlining comes in three different tones.

Engines and transmissions

The new Audi A4 Cabriolet is being launched with a choice of four engine versions, all of which are longitudinally installed. The two highly modern petrol engines with FSI petrol direct injection for the new A4 Cabriolet: the 188 kW (255 bhp) 3.2 V6 and the turbocharged two-litre four-cylinder 2.0 TFSI, which delivers 147 kW (200 bhp). These combine high performance with a spontaneous response to every movement of the accelerator pedal and a peak-torque range at a high level. The 1.8 T which develops 120 kW (163 bhp) is also available.

Diesel enthusiasts can order the immensely powerful 3.0 TDI with common rail injection and piezo injectors. Other engines will be added at a later date.

This modern TDI engine, which made its debut a few months ago in the large A8 and A6 saloons, develops an output of 171 kW (233 bhp) in the A4 Cabriolet. This potent V6 makes a torque of 450 Nm available between 1,400 and 3,150 rpm.

These engines deliver their power to the road either via the front wheels or by means of quattro permanent four-wheel drive (standard on the 3.0 TDI quattro and the 3.2 FSI quattro). A 6-speed manual gearbox is available for the various

A4 Cabriolet models, as is the continuously variable multitronic automatic transmission. This revolutionary Audi transmission technology is available for the front-wheel-drive versions of the new A4 Cabriolet. The now 6-speed tiptronic transmission with sport program is offered as an option for quattro models.

The petrol engines

3.2 V6 FSI

A new six-cylinder engine is being offered for the A4 Cabriolet for the first time. The 3.2 V6 FSI has all the features of an ultramodern petrol engine: FSI petrol direct injection with demand-controlled fuel supply, four valves per cylinder, a variable intake manifold and continuous camshaft adjustment on both the inlet and exhaust side.

This V6 engine delivers its maximum output of 188 kW (255 bhp) at 6,500 rpm; its peak torque of 330 Nm is available at just 3,250 rpm. The A4 Cabriolet 3.2 FSI quattro accelerates from 0 to 100 km/h in 6.8 seconds. Its top speed is governed to 250 km/h.

More than 90 percent of the engine’s peak torque is available in the wide range between 1,900 and 5,900 rpm – a unique characteristic for a naturally aspirated V6. As far as the driver is concerned, this means a dynamic and forceful response to every movement of the accelerator pedal plus a broad usable speed range up to 7,200 rpm, hefty torque and excellent fuel economy: an average consumption of 10.9 litres of Super grade fuel per 100 km is the best evidence of this engine’s efficiency and the special abilities of FSI technology.

The 3.2-litre V6 has been designed with maximum space efficiency in mind. Measuring just 360 millimetres in length and 430 millimetres in width, this aluminium engine weighs a mere 169.5 kilograms – which means substantial benefits in terms of driving dynamics.

As on Audi’s new V-configuration engines in general, the cylinders are arranged at an angle of 90 degrees, and the distance between cylinders is 90 millimetres. The cylinder bore of 84.5 millimetres and cylinder stroke of 92.8 mm add up to an overall engine capacity of 3,123 cc.

The term “petrol direct injection” underlines the central feature of FSI technology: unlike an engine with indirect injection, fuel is injected directly into the combustion chamber. An injection system with a newly developed single-piston high-pressure pump operating on demand ensures exactly the right supply of fuel, delivering precisely the volume required for building up operating pressure between 30 and 110 bar.

In the intake tract, also comprising the two-stage variable intake manifold, moving charge-movement flaps provide the necessary tumble effect, swirling the induced air around depending on operating point. To reach the high specific power and torque figures, a new FSI combustion process was developed – with potential for worldwide use and designed to run on 95/91 octane (RON) fuel.

The camshafts, oil pump and balancing shaft are all driven by a four-piece chain drive of the same type as in the 4.2-litre eight-cylinder unit.

Fine-tuning of the exhaust system offers the driver yet another bonus: the distinctly sporty but never intrusive sound of a genuine six-cylinder unit, making the qualities of the engine a truly sensory experience.

The 2.0 TFSI

Another premiere in the range of petrol engines for the new Audi A4 Cabriolet is the 2.0 TFSI, which was awarded the title “Engine of the Year” in its class by a high-ranking jury of specialist journalists. This is the first time that the combination of turbocharger and FSI petrol direct injection has been offered for a convertible. However, this technology has already been used in an open-top Audi: in the five-times Le Mans winner, the Audi R8, one of the most successful racing cars of all time.

The 2.0 TFSI’s maximum torque of 280 Nm is available from just 1,800 all the way up to 5,000 rpm. This exceptionally broad torque plateau on the one hand permits a fuel-efficient driving style with few gearshifts, and on the other hand means that only light accelerator action is needed to produce assertive thrust and a spontaneous unleashing of power.

This technology lends the A4 Cabriolet 2.0 TFSI flexibility values that are on a par with much larger-capacity sports cars.

It is moreover impressive how spontaneously the new turbo engine always responds to accelerator action, and how assertively it translates pedal movement into acceleration.

The Audi A4 Cabriolet 2.0 TFSI with 6-speed manual gearbox accomplishes the 0-100 km/h sprint in only 7.9 seconds; its powerful 147 kW (200 bhp) engine is capable of taking it up to an impressive top speed of 238 km/h.

The intake manifold on the 2.0 TFSI is made from a high-tech plastic. It also integrates the charge movement flaps whose position is adjusted by a continuous-action pilot motor. The optimum movement of the airflow, or tumble, can thus be controlled on the basis of the engine-speed and load conditions. The fuel is injected via a common rail system supplied by a demand-controlled high-pressure pump.

The fuel is injected directly into the combustion chamber via an injector positioned at one side between the inlet valves. The fuel-air mixture is distributed purely homogeneously within the combustion chamber. This provides a distinctive characteristic, placing the emphasis on high performance and agile responsiveness at all engine speeds.

The four-valve cylinder head with low-friction roller cam follower drive has a modified inlet duct geometry that produces even higher tumble values than the naturally-aspirated FSI engine. In addition to greater refinement, this brings about superior knock resistance, and therefore improved efficiency.

The 1.8 T

A successful engine version will also be included in the range when the new Audi A4 Cabriolet is launched: the 1.8 T four-cylinder which delivers 120 kW (163 bhp). This is an outstanding example of how a modern turbocharged four-cylinder engine can combine high power output with excellent refinement.

Instead of priming its small, very responsive exhaust turbocharger for a peak output value, Audi has placed the emphasis on achieving a substantial, ideally accessible torque curve across a wide range.

It encourages the driver to move up the gears earlier on, so that a more economical higher gear can be used more frequently and for longer periods. All this is fully compatible with ample driving enjoyment.

Peak torque of 225 Nm is reached at an engine speed of just 1,950 rpm. This torque remains constant up to 4,700 rpm. This means that maximum torque is always available in the predominantly used driving/engine-speed range.

The A4 Cabriolet 1.8 T with front-wheel drive and a manual gearbox consumes just 8.5 litres of fuel per 100 kilometres. 163 horsepower accelerate the Cabriolet to a top speed of 226 km/h, and from 0-100 km/h in a mere 9.4 seconds.

The diesel engines

The 2.0 TDI

Driving pleasure and economy, refinement and environmental compatibility: the 2.0 TDI four-cylinder unit with pump-injector technology is making its debut in the Cabriolet as a highly talented all-rounder. The particular strengths of this engine are its high out-put and powerful torque, combined with equally impressive economy.

A maximum output of 103 kW (140 bhp) and peak torque of 320 Nm, available between 1,750 and 2,500 rpm, make this the most powerful and dynamic four-cylinder diesel that Audi has ever installed in its cars. Performance on the road is correspondingly impressive: the 2.0 TDI with 6-speed manual gearbox accelerates to 100 km/h in 9.7 seconds and continues on up rapidly to its top speed of 212 km/h.

Two other fortes of the 2.0 TDI four-cylinder engine are low fuel consumption – 5.7 litres of diesel fuel per 100 km – as well as compliance with the EU4 emissions standard. A diesel particulate filter is standard.

The refinement of this four-cylinder unit in the new Audi A4 Cabriolet is outstanding. A balance shaft module with two shafts rotating in opposite directions helps to reduce engine vibrations extremely effectively.

The 3.0 TDI V6

A genuine power pack is being introduced in the Audi A4 Cabriolet in the shape of the new three-litre six-cylinder unit. Compared with the competition, this engine offers truly impressive power and torque potential: 233 bhp and 450 Nm. Maximum torque is available at a mere 1,400 rpm and giving the driver forceful acceleration at all speeds.

This means performance on the road that even many a sports car will find hard to match: the speedometer needle touches the 100 km/h mark after just 7.3 seconds, and the top speed of the A4 Cabriolet 3.0 TDI quattro is 242 km/h.

Further fortes are the engine’s highly efficient acoustics and compliance with the strict EU4 emissions standard. A diesel particulate filter is fitted as standard.

Featuring turbocharger technology and map-controlled, cooled exhaust-gas recirculation, this V6 four-valve power unit is the first six-cylinder TDI in Audi’s new family of V-engines. The camshafts, balancing shaft and oil pump are driven by chains.

This engine is remarkable for its very compact dimensions, measuring just 444 millimetres in length. This is also an important step toward achieving an overall engine weight of just 219 kilograms. This benefits not only the car’s power-to-weight ratio, but also the weight distribution – two factors crucial to the superior driving dynamics of the new A4 Cabriolet 3.0 TDI quattro.

Common rail technology with piezo inline injectors

Fuel injection is the task of a latest-generation common rail system. It features a high-pressure pump and one rail per cylinder bank. The maximum injection pressure reaches 1,600 bar. This high injection pressure results in even finer atomisation of the fuel and therefore in very good mixture preparation and more efficient combustion.

The piezo injectors are undoubtedly the most important innovation of the new common rail system. The injection process makes use of the piezo effect: a voltage is applied to ceramic which changes its crystal structures. The result is a minimal geometric change which – supported by a hydraulic element – mechanically triggers the opening of the injector needle.

The piezo injectors offer multiple advantages compared with conventional solenoid valves. The moving mass at the injector needle is for instance reduced by no less than 75 percent, from 16 to 4 grams in each case.

This enables considerably smaller and more precisely metered injection quantities. At the same time, piezo technology allows a higher injector needle speed.

The number of injection processes per combustion cycle can thus be varied almost at will. Audi’s TDI development engineers opted for up to five injection processes for the 3.0 V6: in addition to the main injection process, double pilot injection takes place at the lower end of the speed range and single pilot injection in the medium speed range.

This strategy produces both lower emissions and a smoother combustion process, the benefits of which are most immediately apparent in the engine’s acoustic behaviour.

Its average consumption over 100 kilometres is just 7.9 litres of diesel. In practice this ob-viously means a very significant cruising range, the new A4 Cabriolet 3.0 TDI quattro being able to approximately 800 kilometres on one tank of fuel.

Transmissions

The supreme fuel economy and dynamic performance offered by the new Audi A4 Cabriolet also results from the standard usage of 5-speed and 6-speed manual gearboxes and 6-speed automatic transmissions with a wide range of gear increments. The current generation of the continuously variable multitronic transmission now has seven predefined transmission ratios that can be preselected as an alternative.

Ultramodern manual gearboxes

The manual versions of the new Audi A4 Cabriolet come with the current generation of ML transmissions.

This gearbox is noted for its closely spaced, sporty ratios and extremely precise, crisp, short gearshifts. Thanks to a special mount for the selector forks, the gear lever is effectively protected against driveline vibrations; the driver does not feel the gear lever trembling at all.

Internal friction reduced by a series of measures increases the efficiency of the manual gearbox. This means that engine power can be converted even more efficiently into forward propulsion.

The 6-speed tiptronic with sport program

The 6-speed tiptronic transmission is available for the particularly high-torque 3.2 FSI and 3.0 TDI power units in conjunction with quattro permanent four-wheel drive. This transmission enables engine potential to be converted in a supreme synthesis of dynamism and operating convenience.

Weight reduction, a fast and crisp gearshift, as well as an optimised gearshift strategy help to combine the superior convenience of automatic gearshift with the sporting performance so typical of the A4.

Compared with its 5-speed predecessor, the new 6-speed gearbox is 14 kilograms lighter; its overall weight is a mere 115 kilograms.

Again compared with a 5-speed automatic transmission, the overall spread of gear ratios is up by 18 percent on average. This means a much improved accelerating performance in the low gears, and a clear reduction in engine speed and consequently a reduction in both noise level and fuel consumption at high speeds.

The shifting speed of the new 6-speed tiptronic has also been significantly optimised. The driver benefits from more spontaneous gear changes particularly when downshifting.

Both in stage D and in the S sport program, the electronics respond efficiently to parameters such as lateral and longitudinal acceleration as well as to the movement of the accelerator pedal. This helps to prevent any unwanted upshifts when cornering.

Continuously variable multitronic

After making its production debut successfully in the year 2000, Audi’s continuously variable multitronic automatic transmission is again offering its superior qualities in the new A4 Cabriolet, combining the benefits of a manual gearbox with those of a geared automatic transmission. Fortes typical of multitronic are smooth but very dynamic acceleration as well as convenient operation and the efficient transmission of power.

The high standard of operating convenience offered by multitronic exceeds that of a conventional converter-type automatic transmission, while in terms of dynamic performance and economy, multitronic can by all means be compared with a manual gearbox. If the driver wishes to actively choose the appropriate transmission ratio, he is able to do so at the gear lever or using the optional shift paddles on the steering wheel, now providing no fewer than seven predefined gear ratios.

Numerous reinforcements and adjustments, as well as optimised cooling, serve to significantly enhance the performance of Audi’s continuously variable automatic transmission. The multitronic is now even able to convey torque levels of up to 330 Nm, thus qualifying as an ideal partner even for the most powerful V6 engine in the range, the 3.2 FSI which develops an output of 255 bhp and 330 Nm of torque.

Modified for the new Audi A4 Cabriolet, the multitronic variator spans an even wider range of gear ratios: the overall ratio between the largest and the smallest gear transmission ratio is 6.25, virtually ideal for such a transmission. This on the one hand permits dynamic, sports-style acceleration using the largest possible ratio, while on the other hand the engine’s fuel-saving potential is fully exploited using the smallest ratio.

A further special feature is the ability of the electronics to emulate the functions of a manual gearbox. For the latest multitronic version, Audi has opted for no fewer than seven forward gears which the driver can activate using the one-touch function in the second shift gate or by pressing the shift paddles on the steering wheel (optional extra).

These seven gearshift stages are memorised by the system as fixed shift programs. Depending on which gear the driver selects, the controller is supplied with the ratio as a set point, which it establishes and maintains. Even these manually prompted gearshifts take place smoothly and jolt-free, satisfying the desire for sports performance.

quattro permanent four-wheel drive

25 years of quattro: with the introduction of quattro permanent four-wheel drive a quarter of a century ago, Audi revolutionised drive technology for passenger cars. The six-cylinder versions of the new A4 Cabriolet are again available with quattro drive, thus giving it a unique market position in its segment.

Its major strength lies in capabilities that have come to be regarded as a matter of course over the past 25 years: a persuasively superior dynamic performance and driving safety, and a distinctively superior form of travel.

A vehicle with permanent four-wheel drive can translate significantly more traction and consequently higher cornering forces into propulsion. This in turn means greater driving enjoyment and safety for the driver. Improved directional stability and much lower susceptibility to cross-winds also characterise the superiority of the Audi A4 Cabriolet quattro.

On the new Audi A4 Cabriolet, a Torsen differential automatically ensures the optimum distribution of power between all four wheels. This system is also used on Audi’s highest-performance vehicles – the A8 as well as the 420 bhp RS 4, for example.

The name “Torsen” is a contraction of the two terms “torque” and “sensing”. The Torsen differential is a self-locking worm gear.

The advantage of this is that the locking action is only prompted by the driveline. Yet this type of differential accommodates differences in speed when the brakes are applied and when cornering.

Normally the power is split 50:50 between the two pairs of wheels, but in extreme cases the entire propulsive power can be diverted to either pair. In the event of more than one wheel encountering considerable slip, the electronic differential lock EDL can even concentrate this power on one wheel.

Dynamic suspension

Dynamics and comfort, easy handling and active safety at the very highest level: on the basis of these strengths, Audi is demonstrating its proverbial “Vorsprung durch Technik” with the new A4 Cabriolet’s dynamic suspension. Agility and ride comfort are equally impressive.

This road behaviour is the result of extensive modifications both in the area of elastokinematics as well as to the spring and shock absorber settings.

The predecessor’s tried-and-tested basic geometry has been adopted at both front and rear: four-link front suspension and the highly complex self-tracking trapezoidal-link rear suspension. Both consist primarily of light-alloy components resulting in a low unsprung mass.

All versions of the Audi A4 Cabriolet have disc brakes at the front and rear; the front discs are ventilated. Their dimensions have been adapted to the increased performance potential of the new generation of engines. Excellent controllability, spontaneous response and above all considerably reduced braking distances are the result.

The front suspension

On the four-link front suspension layout, each wheel is located by four aluminium control arms. Large-volume rubber components are used as the damper mounts on the new suspension design. This helps to effectively isolate the shock absorbers acoustically.

Several mounts as well as the considerably stiffer track rods on the front suspension have been adopted from the high-performance S4. The mounts for the control arm originate from the new Audi A6.

Together with the new shock absorber settings, this results in a particularly sensitive response to steering movements and even more precise feedback from the road. In other words, extremely dynamic behaviour which is isolated almost completely from front-wheel-drive influences.

High-tech rear suspension

The new Audi A4 Cabriolet comes with one of the most complex, but also most efficient, rear suspension layouts around.

The trapezoidal-link rear suspension makes for top-quality ride comfort on all models, coupled with dynamic behaviour that will amaze the driver of many a competing model.

The trapezoidal link is made from hollow-section aluminium. This torsionally and flexurally rigid link absorbs a large portion of the forces acting on the wheel. Together with the track rod located behind it, it thus determines the elastokinematic behaviour of the axle.

This design is notable for its low weight as well as its outstanding space efficiency. The compact design permits a low load floor in the luggage compartment on all versions.

All wheel control elements pivot on the resiliently mounted subframe via rubber-metal mounts which isolate axle vibration very effectively from the body. Moulded rubber mountings are also used for the suspension springs between the trapezoidal link and the body’s longitudinal member. Here again, the material chosen provides excellent acoustic insulation.

The twin-tube gas-filled shock absorber is connected to the wheel carrier, so that a direct-ratio effect is obtained. Combined with the separately mounted spring, this ensures a particularly sensitive response from the shock absorber.

The trapezoidal links and wheel carriers on the Audi A4 Cabriolet now also originate from the S4, a car whose suspension has demonstrated its all-round superiority in numerous individual and comparative tests conducted by the trade press. However, several mounts and the shock absorbers, which are considerably larger than on the previous model, have been adopted again from the A6.

Thanks to the precision work that has gone into modifying the rear suspension set-up, the dynamic qualities of this basic structure are demonstrated even more effectively. This all adds up to agility and excellent directional stability, outstanding straight-line running and a high level of comfort without any disturbing movements of the body.

The steering: precision and lightness

The new Audi A4 Cabriolet has hydraulically assisted rack-and-pinion steering bolted rigidly to the suspension-strut cross member.

Audi’s developers have achieved an optimum steering layout in terms of safety for the A4 Cabriolet. Because the steering column is mounted in two universal joints, it can be telescopically disengaged in the event of a crash, to isolate it from the steering gear and protect it against bulkhead intrusion.

The dictates of lightweight design even extend as far as the design of the steering wheels for the Audi A4 Cabriolet: for reasons of weight, the single-section skeletons are die-cast in magnesium.

With the exception of the 1.8 T, all new Audi A4 Cabriolet models come as standard with hydraulic rack-and-pinion steering, featuring servotronic speed-dependent power assistance. The development goal here was to provide the highest conceivable standard of sporty steering precision and improved steering comfort.

The refined servotronic system enables the driver to manoeuvre into parking spaces with a minimum of steering effort and maximum accuracy, as well as providing a clear response from the road at higher speeds. The system also offers a high level of sensitivity around the straight-ahead position and even more comfortable initial response behaviour.

Road behaviour: a policy of neutrality

An excellent standard of comfort and superb traction when coming out of even the tightest of curves, neutral, clearly defined self-steering characteristics and, finally, maximum agility. These were the requirements to be met by those whose task it was to develop the new suspension.

Such targets can only be attained by coordinating all new and modified elements to a high standard of precision. The role of the new self-tracking trapezoidal-link rear suspension in the overall package is of course particularly significant. Its elastokinematic properties ensure above all the desired precision of response, while significantly pushing back the handling limits.

On the circular test pad, the most revealing gauge of behaviour close to these limits, the Audi A4 Cabriolet needs only a slight increase in the steering wheel angle to remain on course at moderate to high lateral acceleration.

From the driver’s standpoint, the effect is clear enough: the Audi A4 Cabriolet remains unruffled even when close to the adhesion limits, and stays on the chosen line with controllable and strictly neutral behaviour.

At the same time, body movements even in S-bends remain moderate, without any of the loss of comfort that might be expected from this dynamically firm layout. A positive effect that is preserved even in a wide variety of load conditions.

Safety as standard: new ESP generation

All new Audi A4 Cabriolet models come with the latest-generation electronic stabilisation program, ESP 8.

This system comprises the anti-lock braking system ABS with electronic brake-force distribution EBD and hydraulic brake assist, which automatically increases brake power in panic-braking situations. Together with the yawing moment controller, the traction control system ASR and the electronic differential lock EDL provide the foundation for ESP safety.

The system has been developed to an even higher standard in terms of both electronics and hydraulics. New pressure control ensures even more precise intervention of the ESP stabilising functions in accordance with the given situation, particularly when the car is understeering. In the event of excessive understeer, all four wheels are braked if necessary so that the vehicle can be returned to its original course.

Yet another new feature is the brake disc wiping function integrated into ESP. This helps to keep the brake discs largely dry on wet roads, even if the driver has not braked for a long time. To provide this effect, the brake linings are pressed against the discs under low hydraulic pressure at regular intervals, ensuring even more spontaneous brake response under wet conditions, too. This process goes unnoticed by the driver.

For the first time, the new Audi A4 Cabriolet is equipped with a two-stage ESP deactivation button. A brief press of the button deactivates the ASR traction control system only. This is sometimes necessary in order to be able to pull away in deep snow or on gravel. Even then, however, the EDL and ABS functions remain operative.

Wheels and tyres

The A4 Cabriolet is fitted as standard with 7 x 16-inch alloy wheels, shod with size 205/55 R16 or, in the case of the six-cylinder models, 215/55 R16 tyres. As an option, the new Audi A4 Cabriolet is available with a choice of a further eight wheels measuring up to 7.5 x 17 inches and running on tyres up to 235/45 R17 in size. In winter, too, the A4 Cabriolet driver has the choice of three wheels up to 7.5J x 17 inches in size and running on 235/45 R17 tyres.

All new Audi A4 Cabriolet models come as standard with Audi’s tyre mobility system, but may also be provided with a spare wheel as an option.

Audi is offering two SST tyres (self-supporting tyres) for the first time. Thanks to the tyres’ reinforced side walls, these enable the driver to continue as far as the next Audi dealer if a tyre suffers a loss of pressure. Audi offers two designs – a painted and a polished two-colour wheel. The range also includes a winter wheel.

A direct tyre pressure monitoring system is also available as an optional extra. This system monitors the tyre pressure and temperature of each individual wheel. In the event of a loss of pressure, it informs the driver optically via the display in the instrument cluster.

To provide this function, the signals from the wheel’s electronic control unit are transmitted wirelessly to the central vehicle electronics. There are two warning stages: a pressure loss of more than 0.3 bar at a wheel activates a yellow warning lamp. This tells drivers to check their tyre pressure and top up the air to the correct level at the next opportunity. If tyre pressure is more than 0.5 bar below the limit required or if the tyre is losing pressure quickly, a red lamp lights up urging drivers to stop immediately and remedy the problem.

The system is also able to take into account minor changes in temperature and pressure caused, for instance, by intense sunshine or hot air coming from the engine, thus avoiding any false alarms.

Systematic safety

The new Audi A4 Cabriolet remains faithful to the manufacturer’s best tradition of safety. A rigid body structure and meticulously calculated deformation properties, in conjunction with ultra-modern restraint systems – such as the new two-stage front airbags – and, last but not least, outstanding technical concepts such as roll-over bars projected behind the rear seats if the car turns over, create an outstanding level of occupant safety.

The floor assembly, where large-volume sills with an internal aluminium profile and sturdy cross-members direct and absorb the impact energy, provides a sound basis.

In a side impact, the occupants are protected by additional energy-absorbing side members in the doors as well as tube-reinforced side panels in combination with the side airbags.

The driver’s airbag is triggered in two stages depending on impact speed. An extensive system of crash sensors ensures that the front and side airbags are ignited at exactly the right moment. In addition to the upfront sensors, the triggering system comprises several remote satellite sensors at the sides.

The front airbag on the passenger’s side can be deactivated by key. This is an important function, particularly if a child is to travel on the passenger’s seat in a child car seat. All Audi A4 Cabriolet models have provisions for mounting Isofix child seats on the rear seats. A seat belt reminder function for the driver is also part of the standard specification on all new Audi A4 Cabriolet models.

One of the biggest safety risks for the passengers of a convertible is if the car rolls over. Audi has taken account of this with an extremely rigid windscreen frame and active roll-over bars. The bars are located in cassettes behind the rear seats, and shoot up within fractions of a second if necessary.

The seats also make a valuable contribution towards occupant protection. The front seats are integral steel structures with extremely rigid cross-bracing. They thus largely retain their shape in a side-on crash. This is of crucial benefit in keeping the survival zone intact.

Individuality and more

The new Audi A4 Cabriolet is positioned in the top segment of the midsize class. It stands out for a range of standard equipment with quality and comfort attributes that would not be out of place in the luxury class. The scope for every owner to customise his or her own car is equally important. Personal style and the desire for an unmistakable touch of individuality, specifically in the car’s interior, play an even greater role for the Cabriolet than for the Audi A4 saloon or the A4 Avant.

Even the standard version of the new Audi A4 Cabriolet leaves practically nothing wanting. And it offers the driver a broad range of possibilities for fulfilling his or her very own idea of contemporary, stylish mobility.

Appearance made to measure

Customers can choose from 13 exterior colours, five of which are being offered for the first time for the Audi A4 Cabriolet. The range also includes four hood colours and three different tones for the headlining. The wheel range comprises nine summer and three winter wheels of up to 7.5 x 17 J in size, with tyres up to 235/45 R17. These also include three SST wheels with run-flat characteristics which allow drivers to continue their journey for a limited distance if a tyre suffers a loss of pressure. Additional wheel versions up to 18 inches in size are available from quattro GmbH.

Audi A4 Cabriolet drivers can choose between a number of material and colour combinations. The equipment concept offers supreme flexibility and individuality.

All components are colour-coordinated, with the result that every configuration creates a harmonious overall appearance.

The interior consequently satisfies virtually every design requirement. The materials used are without exception of the highest quality – a characteristic that is conveyed not only visually, but also by their feel. As well as Olympic cloth upholstery, Audi also offers a leather/cloth and a leather/Alcantara combination (for the sports seats) in various colours. Pearl Nappa upholstery is also available.

Brushed aluminium inlays on the dashboard and doors, and door sill trims with aluminium inserts are all part of the standard specification. Wood inlays in Walnut brown or Fine grain birch wood grey or beige are available as options.

The standard equipment

The perfect climate can be enjoyed in the new Audi A4 Cabriolet thanks to the deluxe automatic air conditioning. The standard version of this system, which also includes a sun sensor, allows the temperature to be adjusted separately for the driver and front-passenger sides. This system, which is equally important to comfort and safety, is part of the standard equipment specification of all new

A4 Cabriolet models.

The newly designed four-spoke steering wheel with single-frame design feature can be adjusted both vertically and horizontally. A4 Cabriolet 2.0 TFSI, 3.2 FSI and 3.0 TDI models are fitted with servotronic power steering where the degree of assistance provided is dependent on vehicle speed.

The driver’s and front passenger’s seats have manual fore/aft and height adjustment.

The safety equipment featured as standard in the new-generation A4 Cabriolet is equally impressive. In the event of a collision, the car’s occupants are effectively protected by the robust structure of the body with predefined deformation and a highly stable passenger cell. And in conjunction with seat belt tensioners and belt-force limiters, the full-size front airbags and front side airbags offer the driver and passengers a high level of protection. The driver’s airbag is triggered in two stages depending on the severity of the accident.

Active safety benefits from the latest-generation electronic stabilisation program ESP 8.0 complete with hydraulic brake assist, anti-lock brake system ABS, electronic brake-force distribution EBD, the traction control system ASR and the electronic differential lock EDL.

The brake-disc cleaning function is also an integral part of ESP. In wet conditions, this removes the film of water from the discs at predefined intervals, thus helping to reduce the vehicle’s braking distance considerably.

The motorway indicator function improves safety when overtaking: if the indicator lever is pushed up or down to just before its detent position and then released, the indicators flash three times.

Electric windows at front and rear – with finger protection – and electrically adjusted door mirrors optimise operating convenience.

The central locking is equipped with radio remote control, allowing the car to be locked and unlocked from quite some distance away. The car can easily be identified for example on a large, anonymous car park by unlocking it with the remote control; its indicator lights then flash making it easy to locate.

The instrument cluster’s central display shows for instance the distance remaining on the fuel in the tank, the outside temperature and the distance remaining to the next service.

Good visibility is guaranteed by the standard clear-glass headlights with free-form technology. High-performance halogen fog lights integrated into the bumper are also part of the standard specification.

All A4 Cabriolet models are fitted as standard with sporty 16-inch alloy wheels.

The storage package can accommodate numerous personal items. It comprises drawers under both front seats and luggage nets on the back of the front seats. The standard specification also includes a load-through hatch with ski bag.

The automatic hood also provides maximum convenience. It can be opened and closed extremely quickly at the press of a button. This can be carried out at a speed of up to 30 km/h – in slow-moving city traffic, for example. The rear window is made of glass and can be heated – a further indication of the A4 Cabriolet’s suitability for all-season use.

Optional extras

Thanks to the higher material density of the hood layers and optimised padded layer, the acoustic hood reduces noise entering the interior to almost the same level as in the Audi A4 saloon. This advances the Cabriolet to the top of its class.

If only the front seats are occupied, the wind deflector offers additional protection against turbulence when the hood is down.

As many as nine alloy wheels of sizes 7 x 16 to 7.5 x 17, available from the launch date, give drivers a further means of enhancing the characteristic appearance of their new Audi A4 Cabriolet. Tyre sizes up to 235/45 R17 ensure an uncompromisingly sporty character that is manifested in ways other than just visually.

In addition, quattro GmbH offers six other alloy wheel versions of sizes from

7.5 x 17 to 8 x 18 inch.

The range also comprises wheels with winter tyres: three cast aluminium wheels of sizes 7 x 16, 7 x 17 or 7.5J x 17, shod with tyres up to 235/45 R17 in size, are available.

The new Audi A4 Cabriolet provides the perfect infotainment experience.

The Audi navigation system plus with MMI operating logic and navigation DVD not only enables almost limitless navigation throughout Western Europe, but can also be used to play audio CDs. Its operating principle follows the same clear logic as the Audi MMI, familiar from the A8 and A6. The 6.5-inch colour display shows the map and the visual route description, while the driver information system translates the corresponding directions into pictograms and adds information on distances and arrival time.

The new storage medium of the DVD for the navigation system provides more than ten times the storage capacity of a conventional CD-ROM, coupled with a noticeably faster access time.

Almost the entire road network of Western Europe can now be stored on a single data carrier, overcoming the inconvenience of having to change the CD when the driver crosses a national border. A further advantage is that the navigation system calculates the route much more swiftly than on CD-based systems. This is particularly noticeable during map loading and when using the zoom function.

The bird’s eye view on the screen, which can also be split if required, facilitates visual orientation on the map.

The audio systems offer the ideal combination of high convenience and extensive features for every customer:

- chorus with cassette player, nine loudspeakers and diversity aerial for optimum reception

- concert with CD player (instead of cassette player)

- symphony with cassette player and a 6-CD changer as well as a diversity aerial

The BOSE sound system (in conjunction with an Audi audio system or navigation system plus) additionally provides a concert hall atmosphere in the

A4 Cabriolet.

Communication in a broader sense likewise takes place while the car is being manoeuvred into a parking space: the acoustic parking system helps to estimate the exact distance to the next car – whether to the front or the rear – by means of ultrasonic signals. Sensors integrated discreetly into the bumpers measure the distance and prompt acoustic signals which let the driver know how much clearance remains.

Electric adjustment can be ordered as an option for the driver’s and front passenger’s seats. The seat positions can be stored by a memory function (optional extra). The position of the door mirrors can also be memorised.

On warm days, the optional cooling box in the glove compartment is a welcome feature: the contents are cooled by the automatic air conditioning while the car is on the move and remain at a low temperature for some time after the engine has been switched off.

The Audi range of optional extras also offers perfect solutions for when the sun goes down: the best examples are the xenon plus headlights with outstanding dipped and main xenon beams and automatic-dynamic headlight range control. They illuminate the area in front of the car evenly and intensively. A headlight washer system in addition comes to the driver’s aid if there is a risk of dirt accumulating. Daytime running lights, which can also be deactivated manually if required, are part of the xenon plus lighting package.

adaptive light including xenon plus ensures even better visibility. Featuring swivel headlight units, the dynamic cornering light illuminates twists and turns in the road far more intensively, above a speed of 12 km/h.

The standard seats in the new Audi A4 Cabriolet provide maximum comfort on long journeys. However, they too can be customised to meet your individual requirements even more perfectly, for example with a 4-way electric lumbar support for both front seats.

The front sports seats in the range of optional extras for the Audi A4 Cabriolet offer an ideal synthesis of excellent lateral support and maximum seating comfort. They can also be combined with electric adjustment and a memory function as an option.

And while on the subject of sport, even a car as dynamic as the Audi A4 Cabriolet may arouse the desire for a setup that makes even fewer compromises. This requirement, too, has already been taken into account in the S line range for the new Cabriolet.

In the S line sports package, the sports suspension by quattro GmbH, which lowers the body by 10 millimetres and includes firmer shock absorber/spring rates and 9-spoke 7.5 x 17 wheels (or even 8 x 18-inch wheels as an option), adds an attractive visual touch and ensures even better driving dynamics.

The S line sports package also includes visually identifying features such as badges in the front grille and on the rear side rubbing strips, special inlays for the driver’s area, sports seats with lumbar support for driver and front passenger plus electric adjustment and 3-spoke leather sports steering wheels.

The S line exterior package gives the body a particularly sporty look thanks to a radiator grille with S-line grid pattern, an individual design for the front bumper and a diffuser trim at the rear end.



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