The new lexus rx300: changing the way an suv should be key points
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BUILD QUALITY: ACHIEVING BEST IN CLASS NVH The construction of the new Lexus RX300 body further enhances the car’s dynamic capabilities, efficiency and durability. The body structure is manufactured from high strength sheet steel ensuring the highest levels of body rigidity and a light weight. The use of additional fastening and reinforcement in the front suspension tower, front cowl panel and around the entire back door opening all contribute to the vehicle’s rigidity and NVH performance. There is also strategic use of sound absorbing and vibration damping materials. The build quality of the new RX300 plays a major role in both NVH and perceived quality. Accurate ‘cutline management’ yields a big improvement in fit between lamp units and body panels. SAFETY: A CLEAR LEADER IN THE SUV SEGMENT One of Lexus’s highest priorities for the new RX300 is an unparalleled level of occupant safety. Not only is the new RX300 a class leader in its own right, it is expected to influence the safety provisions in all SUVs to come, setting new standards by combining a vast range of innovative technologies into an integrated approach embracing structural, active and passive safety. Uppermost are the excellent driving dynamics, further aided by Vehicle Stability Control (VSC), Traction Control (TRC) and Brake Assist (BA) technology. Additionally, the new RX300 carries more active and passive safety equipment than any other vehicle in its segment. PASSIVE SAFETY Standard equipment includes multi-stage driver and front passenger SRS airbags. These work in conjunction with impact absorbing structures in the front end of the vehicle and the pretensioner-equipped seat belts to reduce shocks to the head, chest and legs in the event of a frontal collision. The multi-stage driver and passenger airbag system is linked to a seat position sensor, crash severity sensor and the seatbelt buckle switch (which detects whether or not the belt is fastened). Using information from these sources, it judges the best inflation level for each airbag according to the immediate circumstances. These ‘intelligent’ airbags, by neither under nor over-inflating, greatly enhance the security of driver and passengers. The provision of a driver’s SRS knee airbag in the RX300 – a first for the segment – is likely to reduce significantly injuries to the legs, which are common in major frontal impacts. The knee airbag deploys from the lower part of the instrument panel at the same time as the front airbag. It is primarily designed to reduce injury from contact with steering column and lower dashboard structures, but has also been found to reduce head and chest injuries by reducing displacement of the pelvis and rotation of the torso in a major impact. Further protection is provided by an energy absorbing mechanism in the steering column. When a major impact is transmitted to the steering mechanism in a collision, a breakaway bracket separates, causing the entire column to move forward, away from the driver. Energy-absorbing plates and brackets also reduce impact forces delivered to the steering wheel. To complement this feature, the RX300 is also equipped with a collapsible pedal system. In the event of a frontal collision, pedals will disengage and move forward from their original position to minimise potential injuries to the driver’s feet. In the event of a side-impact, the impact-absorbing structure of the RX300 is reinforced by side curtain shield airbags that provide passengers with extra head protection. These inflate from the top of the door frames to help reduce the impact energy transmitted to the driver, front passenger and outer rear seat passengers in the event of a side collision, effectively creating a pneumatic ‘curtain’ over the window area. This side protection is further enhanced by the world’s first use of extra-large SRS Thorax-Abdomen-Pelvis (TAP) Side Airbags. These airbags have a capacity of 16 litres, at least six litres more than conventional side airbags. This means they can reduce the risk of chest and abdomen injuries by spreading the forces over a wider area, covering torso, abdomen and pelvis. In spite of their size, the TAP Airbags are mounted in the seats rather than on doors, so they remain in the ideal position however far back or forward the seat is positioned. In total, the new Lexus RX300 is equipped with nine airbags. Seats in the new RX300 have been designed to WIL (Whiplash Injury Lessening) principles. The design incorporates innovations in headrests and seat backs that decrease neck motion in a rear end collision. By reducing the motion between head and torso, the seats have been shown to significantly lessen the incidence of whiplash injury. To provide optimum safety, the airbags work in conjunction with three-point electronically sensing pretensioned seatbelts, fitted to both the front and rear seats. The rear seat is designed with built-in Seat Belt Comfort Guides to ensure the correct positioning of the seatbelts for children or smaller passengers. An ISOFIX bar for securing child seats has been provided behind the rear seat cushion. In addition, three CRS anchor brackets for securing child seats are provided on the rear seat backrests. The ‘intelligent’ electronic seat belt pretensioners and force limiters allow full freedom of movement under normal circumstances, but instantly restrain the body in an impact. Triggered by the ignition signal from the airbag sensor, the seatbelt pretensioner activates simultaneously with the front airbags. At the start of the collision, if the tension of the seatbelt reaches a predetermined level, the force limiter is activated to reduce the force exerted on the occupant. The overall structural strength of the new RX300 also plays a significant part in protecting its occupants. Reinforcements have been added to the inner and outer rocker panels, front pillars, and roof side rails in order to minimise cabin deformation during a frontal collision. Impact energy from a side collision directed to the cabin area is dispersed throughout the body via the central pillar, reinforcements, side impact protection beams and floor cross members. 
ACTIVE SAFETY The impact absorbing structure and passive safety equipment in the new RX300 are really designed as a final resort. Of perhaps greater importance is the maximisation of Active Safety, the use of design, technology and driving dynamics to avoid potential accident situations in the first place. Electronic traction control (TRC), a multi-channel anti-lock braking system (ABS), with Electronic Brake-force Distribution (EBD), Brake Assist (BA) and a Vehicle Stability Control (VSC) system all add to the vehicle’s dynamic handling characteristics. The purpose of the innovative VSC system is to aid stability during cornering. The system monitors the vehicle's behaviour during cornering and maintains stability by using the car’s ABS and TRC sensors to apply small amounts of asymmetric braking to correct oversteer or understeer before it occurs. The primary roles of the TRC and ABS are to provide stability under acceleration or braking. Further significant safety enhancements are the use of EBD, which uses the anti-lock braking sensors to equalise front and rear brake force distribution and Brake Assist, which interprets a quick push of the brake pedal as emergency braking and supplements the braking power applied to maximise performance in conjunction with ABS. The elevated driving position of the RX300 is itself an important active safety feature. At night or in bad weather the Intelligent AFS, Adaptive Front-lighting System, radically improves visibility when cornering by directing the front headlight low beam towards the inside of a curve. Intelligent AFS is equipped with an electronic controller which calculates the optimum degree of light swivel from information received on vehicle speed and steering angle. LHD model with Intelligent AFS LHD model without Intelligent AFS  
Unlike rival systems which are merely directly linked to a car’s steering, or use additional lights, the Intelligent AFS controls the lighting direction of each headlamp light independently. It is also combined with High Intensity Discharge (HID) headlights with an automatic levelling system and headlamp cleaners. An automatic rain sensing windscreen wiper system on the SE and SE-L versions and a spray windscreen wash system on all models ensure the best possible visibility in poor weather. This is further aided by the use of water-repellent glass, which is specially coated to maintain clear vision through the front side windows. A further aid to active safety is the use of the Lexus Parking Assist Monitor, effectively a TV camera mounted at the rear and a unique feature among luxury SUVs. When reverse gear is selected, an image appears on the navigation display screen on the dashboard. This helps accurate manoeuvring and reduces the risk of collision with low-level objects. Providing a final touch of style, technology and safety at the rear of the new RX300 are combination lamp units which use the latest LED (light emitting diode) technology rather than traditional filament bulbs. In the case of the brake lights, their more rapid response time is a significant active safety item. The LED elements light up 10 times faster than a conventional lamp, between 2 and 15 milliseconds as opposed to 150 to 200msec. This equates to an extra six metres of ‘reaction time’ at 62mph. INTERIOR: ORIGINAL, ATTRACTIVE, WITH A NEW APPROACH TO CONVENIENCE As well as the customary standards of Lexus comfort, ambience, practicality and luxury, the new RX300 combines the latest contemporary design with the highest quality materials and an even higher level of perceived quality. The interior design features ample accommodation, with plenty of storage places; a ‘segment-first’ Power Tailgate; and rear seats that are multi-adjustable, including a ‘flat-floor’ folding system. DESIGN AND PERCEIVED QUALITY Design inspiration for the interior came from not just the automotive industry, but from a wider range of craftsmanship and hand-made luxury goods. High quality musical instruments are a typical example of how different materials can be seamlessly worked to combine both practicality and aesthetic beauty. Lexus designers have spent time with musical instrument craftsmen to learn more of their special timber moulding techniques used in making pianos, violins and guitars. Perceived quality is further enhanced by specially treated interior trim and soft-touch padding that covers the dashboard all the way down to its bottom edge. The airbag aperture for the front passenger has been made invisible. The dashboard architecture matches the front-end exterior design philosophy of the new RX300, in being inspired by wing-like shapes. The main instrument cluster in front of the driver is housed in a distinctive ‘Optitron’ three pod unit with a central speedometer, flanked by tachometer and a multi-function display with fuel gauge, engine temperature and gearshift position read-outs. The dashboard features a distinctive brushed ‘cool metal’ panel in the centre, which is divided into left and right halves. Its shape is elegant and the metallic finish draws attention to the console, which houses the climate and audio controls and a seven-inch touch-sensitive screen for vehicles equipped with satellite navigation system and reverse parking monitor. The central trim is complemented by curved Walnut or Maple wood in the lower console containing the selector lever for the sequential automatic transmission. There are further light wood highlights on the steering wheel, door trims and centre console box between the front seats. The adjustable console box can either slide forwards to give the impression of a continuous sweep from the centre console, or backwards to create a ‘walkthrough’ space between the front seats. CONVENIENCE On the SE and SE-L versions, the leather-upholstered driver and front passenger seats have eight-way electric adjustment, allowing occupants to select the ideal fore/aft seat position; seatback (forward/backward); seat cushion tilt angle; seat cushion height (up/down). With fabric trim, the driver's seat has eight-way adjustment and the passenger seat four-way adjustment. The SE and SE-L also feature a memory function that will store two positions for the driver’s seat, along with settings for the steering wheel and door mirrors. All can be recalled at the touch of a switch on the driver’s side door trim. The rear seats match those in the front, being designed as separate entities to highlight an ‘independent four seat’ approach. A padded central area between the outer two seats acts as a third rear seat. Each rear seat is adjustable fore and aft by 120mm and can be reclined, allowing all passengers to travel in great comfort. The padded central seating area additionally folds down to create a combined armrest and storage box, with two ‘XL’ size cupholders. Three cupholders are provided for front-seat passengers. For more flexible, versatile load carrying, the three rear seat backs on the SE and SE-L models can be folded down in a variety of combinations: 100, 80, 60, 40 or 20 per cent. With the central (20 per cent) section lowered, long loads can extend through from the luggage compartment between the two outer rear passengers. A key feature of the new Lexus RX300 is the power operation of the tailgate, automatically opening and closing at the touch of a button (SE and SE-L versions). It can also be activated at distance using the remote key control fob. For safety, a buzzer sounds when the automatic operation starts. Touch and motor sensors stop the door if there is any obstruction to its closing action. If jamming by any object is detected, the Power Tailgate will immediately move in the up direction. To further aid convenience, the tonneau-type luggage bay cover automatically retracts as the tailgate opens. There are 12V power outlets in the centre console and luggage compartment, while hidden underfloor storage compartments are also accessible in the luggage bay, simply by clicking down their pop-up lids. A further combination of perceived quality and owner convenience is a premium illumination scheme which lights up door handles, centre console, footwells, ignition switch and scuff plates. The Intelligent Illuminated Entry System fitted to SE and SE-L versions uses an ECU to coordinate the activation of the different illumination points with certain actions, such as opening the door and inserting the key in the ignition. It is particularly helpful when getting into or out of the vehicle at night. Further convenience is offered by the Customised Body Electronics System. This allows the Lexus Centre to individually programme the various ECUs to suit the owner’s personal preferences. For example the remote door lock control system can be programmed to respond differently to either ‘one click’ or ‘two click’ pressing of the unlock button; the hazard warning lights can be programmed to respond to input from the remote; and the Theft Deterrent System can be programmed to start automatically 30 seconds after removing the key from the ignition. LOW LEVELS OF NVH In common with all Lexus models, the RX300 sets new standards in its class in terms of NVH. Intensive computer modelling has achieved the best possible application of vibration damping and noise suppressant materials to reduce engine and road noise and increase high-frequency noise absorption. Foamed urethane sponge and foamed seal material are applied to the cabin roof and pillars to reduce wind and road noise, while a large-size dash panel silencer cuts down high-frequency noise. A dash outer silencer and bonnet silencer significantly reduce the noise transmitted from the engine compartment. In place of the traditional underfloor noise damping sheets, the RX300 is the first vehicle of its type to use a new coating-type of foamed damping material that sticks to the entire floor panel, treating it as a single acoustic system. This gives enhanced road noise reduction, while at the same time achieving a 20 per cent reduction in the combined weight of the sound proofing materials. ON-BOARD INFORMATION The RX300’s advanced electronics have also made it possible to provide more features for enhanced convenience, quality and performance. The Lexus Parking Assist Monitor, effectively a TV camera mounted at the rear, is a unique feature among luxury SUVs. When reverse gear is selected, an image appears on the navigation display screen in the centre of the dashboard, helping more accurate and safer manoeuvring and reducing the risk of collision with low-level objects. The display can also show a composite view, with parking guidelines superimposed on the screen to assist the driver. These guidelines include a vehicle width extension to help the driver gauge the width of the vehicle, and a guideline indicating the likely path of the vehicle based on the current steering position. When specified, the same touch-sensitive seven-inch screen displays information from the Lexus Navigation System, trip information, air conditioning controls and a calendar display with memo registration and multi-information display. The Lexus Navigation System uses the Global Positioning System and map data from a DVD to pinpoint the position of the vehicle and display it on screen. The system also provides voice instructions to guide the driver to any pre-selected destination. Vehicles not equipped with the seven-inch touch sensitive centre screen feature a new Multi-Information Display. This LCD panel is located on the top of the centre console and provides information about ambient temperature and trip-related data, such as average speed, average fuel consumption, instantaneous fuel consumption, journey distance from start-up, journey range and elapsed time. AIR CONDITIONING SYSTEM WITH NEURAL NETWORK CONTROL The RX300’s air conditioning system is the most advanced available in any SUV today. The fully automatic system features left/right independent control allowing the driver and front seat passenger to individually select their preferred temperature. Both cold and warm air can now also be conducted directly to rear seat passengers via a new rear face level duct. The system features a Neural Network Control system. This is capable of effecting complex temperature control by simulating the way the human nervous system processes information, similar to a human brain. In previous automatic air conditioner systems, the ECU determined the required air temperature and blower air volume according to fixed calculations from its sensor information. However human sensors are more complex and influenced by the surrounding environment. For example, a given amount of solar radiation can feel comfortably warm in a cold climate, yet uncomfortable in a warm climate. The Neural Network Control system collects and stores a range of data from different environmental conditions to provide enhanced air conditioner control and comfort. The unit is also significantly more energy efficient. Although maintaining the same power consumption, the heater now has greater heating capacity and the air conditioner has additional cooling capacity. Heat exchange efficiency has also been improved. The air conditioner unit is now more compact, with a new, super-slim evaporator and longitudinally-mounted heater. AUDIO SYSTEM: THE EXCELLENCE OF MARK LEVINSON® A final luxury and convenience touch is a choice of advanced audio systems including a Lexus eight-speaker system with an in-dash six-CD player and Automatic Sound Leveliser (ASL). An 11-speaker premium audio system is also offered, developed from Lexus’s unique collaboration with the world’s most exclusive maker of home audio systems, Mark Levinson®. More information about this equipment can be found in the ‘Advanced Features’ chapter. CHASSIS: ENGAGING DRIVING DYNAMICS WITH TYPICAL LEXUS REFINEMENT Subtle enhancements and new technology have been combined in the chassis and suspension of the new RX300 to provide even more engaging driving dynamics in all driving conditions. In addition, a new, optional Air Suspension System offers a still higher level of performance and ride control, together with an auto-levelling function and the ability to alter ride height through a range of 55mm. AIR SUSPENSION: FIRST TIME IN RX300 T
he optional new Air Suspension System offers an even higher level of performance and refinement. It provides greater ride control together with an auto-levelling function, along with four operating modes by which ride height can be adjusted through a range of 55mm and five levels: High (+30mm), Normal, Auto-low (-7.5mm), Low (-15mm) and Access Mode (-25mm). T he system uses pneumatic cylinders instead of the coil springs used in a conventional suspension design. A suspension control ECU analyses information based on the switches, sensors, load and ride input signals to operate the height control compressor assembly, and uses solenoid valves to control the vehicle ride height and attitude. Three vehicle heights can be selected by operating a control switch on the dashboard: The ‘HI’ (High) mode raises vehicle height by 30mm to allow optimum ground clearance and ‘drive-through’ performance on rough roads. The ‘LO’ (low) mode lowers vehicle height by 15mm for better high speed handling, reduced body roll and improved aerodynamic performance. The ‘N’ (Normal) mode helps produce the optimum ride comfort and controllability in normal driving and at speeds above 62mph automatically lowers the vehicle by 7.5mm to provide superior high-speed stability. When the ignition is turned off, the air suspension assumes ‘Access’ mode, lowering vehicle height by 25mm, to provide easier access or exit for driver and passengers, as well as easier loading of cargo. COIL SUSPENSION: FLATTER RIDE WITH IMPROVED COMFORT An improved front MacPherson Strut suspension system includes a new coil spring rate, shock absorber and revised suspension bushes for greater lateral force control and a smoother ride. This is further aided by the exceptional rigidity of the new body structure. In addition to the new components, the front suspension uses ‘Nachlauf’ geometry. This positions the kingpin axis ahead of the axle centre, which delivers excellent straightline stability. The steering feel is also improved by using this geometry. The front suspension also adopts a small level of negative camber, effectively leaning the top of each front wheel inwards, relative to the bottom of the wheel when the vehicle is moving in a straight line. When the suspension is under cornering load, the change in vehicle posture naturally reduces the ground contact camber angle of the outside front wheel, positioning it in the optimum position to handle cornering loads. A key component of any vehicle with MacPherson strut suspension is the suspension upper support. In the RX300 this is designed to transmit the load applied by the spring through its metal structure, while the rubber portion receives only the load applied through the shock absorber. This further improves NVH suppression and suspension control, while the inclining of the centre axis of the coil spring to the outside of the vehicle compared with the shock absorber reduces the lateral force bearing on the shock absorber piston rod, allowing smoother and more accurate operation. The performance of both front and rear shock absorbers features ‘high reaction’ developments to achieve high response and high damping force at small amplitudes. They are also enhanced by the use of multi-leaf type linear control valves, which promote more linear damping. On the front suspension, a rebound spring is adopted to reduce body roll, promote a flatter cornering attitude and create extra vehicle stability during cornering. At the rear of the new RX300, a dual-link strut suspension system is used in combination with a new, more rigid rear axle design. At the same time, there is a new layout for the coil springs and shock absorbers, optimising the suspension geometry to achieve a flatter ride, greater stability and controllability. S TEERING A speed-sensitive rack and pinion steering system is used, with a responsive 3.0 turns from lock to lock. For further comfort and convenience the steering column is electrically adjustable for reach and on the SE and SE-L versions is equipped with a memory function.
The RX300 runs on 225/60 R17 tyres on 17-inch diameter six-spoke alloy wheels or 235/55 R18 high performance tyres on 18-inch diameter five-spoke alloy wheels. In addition to enhancing the vehicle’s appearance and giving optimum driver feedback and cornering performance, these wheels allow larger ventilated front brake discs to be fitted, the diameter increased from 296 to 319mm. An increase in front brake piston size and reduction of brake pedal stroke ensure more linear and powerful braking performance. BRAKE CONTROL SYSTEM Braking performance is further enhanced by a multi-channel anti-lock braking system (ABS), with Electronic Brake Distribution (EBD), Brake Assist (BA) and Vehicle Stability Control (VSC) system. Brake Assist interprets a quick push of the brake pedal as emergency braking and supplements the braking power applied to maximise braking performance in conjunction with the ABS. This overcomes the recognised problem of drivers not applying sufficient force to the brake pedal in an emergency. While the primary role of the ABS is to help prevent the wheels from locking when the brakes are applied firmly or when braking on a slippery surface, EBD utilises the ABS to deliver optimum brake force distribution between the front and rear wheels, according to driving conditions. In addition, during simultaneous braking and cornering, EBD works with the VSC to control the individual brake forces on the right and left wheels, helping to maintain vehicle stability. The VSC system also monitors the vehicle's behaviour during normal cornering. It maintains stability by using the car’s ABS and TRC sensors to apply small amounts of asymmetric braking, preventing the vehicle from slipping sideways as a result of a loss of traction from either front or rear wheels during cornering. This distribution of brake force, which in the past was performed mechanically, is now performed by a skid control ECU. This provides much more precise electronic control for optimum brake force, according to driving conditions. POWERTRAIN: MORE DRIVING PLEASURE WITH GREATER FUEL EFFICIENCY The transversely-mounted high-performance three-litre V6 engine and full-time four-wheel drive system used in the original RX300 have been significantly revised to boost performance and refinement in the new model. The new generation RX300 additionally uses an all-new five-speed, Multi-mode Automatic Transmission and electronically controlled torque distribution between front and rear wheels for even greater efficiency. ENGINE: TECHNOLOGY MAKES THE DIFFERENCE
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Engine speed (rpm) The Lexus RX300 is powered by the most sophisticated and refined petrol engine to be found in a sport-utility vehicle. The 2,995cc, four-cam, all-aluminium V6 remains a technical leader in luxury SUVs by utilising a three-stage variable induction system and an active engine mount, among other technical refinements.
A five-speed automatic transmission is used in the Lexus RX300 for the first time, combined with an improved drivetrain in which the torque distribution between the front and rear wheels is controlled electronically by the Traction Control (TRC), rather than the previous mechanical control by viscous limited-slip differential. The new TRC system provides more precise control, delivering smooth traction even when the throttle pedal is used roughly. The Multi-mode Automatic Transmission, controlled from a dashboard-mounted shift lever offers either full automatic operation or the opportunity to select S-mode and create the driving feel of a sporty five-speed manual transmission vehicle. By moving the selector from ‘D’ to ‘S’, the driver is able to sequentially shift gears with a forward and backward movement of the shift lever, with the shift range position being displayed on the dashboard. As a further convenience while in S-mode, the transmission automatically returns to first gear, whenever the vehicle comes to a standstill. In the D-mode, the transmission is optimised by the electronic throttle control system to give quick downshifts and smooth upshifts. Extra refinement is achieved by the use of a shift control programme, which minimises the shifting of gears when the driver operates the accelerator pedal on a winding road or gradients. The engine and transmission ECUs work together to calculate from the speed sensor signal and engine load, whether the vehicle is travelling up or downhill. If the electronic control module determines the vehicle is heading uphill, it will automatically delay any upshift in the gearbox until it recognises that the ascent is complete. On a downhill gradient, the transmission will shift down the ratios in accordance with the driver operating the brake pedal, minimising the need for brake application. Specifically designed to meet the needs of customers who are already used to the standards of refinement and performance set by Lexus saloons, the RX300 four-wheel drive system is well ahead of traditional ‘off-roaders’ in terms of driveability, comfort, efficiency and safety. The first generation RX300 used a viscous limited-slip centre differential to transfer torque to the wheels which have the most traction. This has been replaced in the new RX300 by a more sophisticated and efficient electronic control system which uses the car’s TRC and VSC systems to ensure seamless distribution of drive, even when alternate wheels would otherwise slip. By discontinuing the traditional limited-slip differential and concentrating on the development of more effective traction and stability control systems, a significant weight saving has been achieved. The TRC and VSC provide superior traction in every situation and are quicker to react than the limited slip differential as the wheel sensors can detect even minimal wheel slippage. The weight saving achieved by the use of electronic control is reflected in both performance and better fuel economy. Aligned to the decision not to include the seldom-used low-range transfer gearbox, with its associated cost, weight and maintenance implications, the RX300 is between 200 and 300kg lighter than many of its segment rivals. Of course, in terms of its powertrain, the new RX300 remains a true Lexus, setting new standards in refinement, beyond the class leading standards established by the original model. Detail developments include the use of a dynamic damper on driveshafts, along with the straightening of the exhaust system and the driveline routes under the car, to minimise resonance and vibration. As hard acceleration is a principle source of vibration, the front section of the driveline is canted forward by two degrees when the car is static to allow it to assume the optimum straight line under acceleration load. Combined with the rigid, low vibration and low noise body structure characteristics, this exceptionally refined driveline contributes to the lowest levels of cabin noise in the vehicle’s class.
Employees develop tools in-house that will make tasks easier and faster and will increase quality. The factory is fully air-conditioned and features coordinated interior colours to create a pleasant working environment. Noise is also carefully controlled. For example, the noise from the 4,000-ton body-stamping machine is absorbed by a giant noiseproof cover and 372mm-thick anti-vibration springs. Cleanliness is regarded as paramount. When the sheet metal rolls arrive at the plant, they are kept in a dirt-free warehouse and wrapped in protective material. Before they go to the press machine, they are carefully cleaned again to make sure there is no dust or particles that could damage the quality of the stampings.
Kyushu has its own recycling centre within the plant, something that is still quite rare in the motor industry, where many waste products are still simply incinerated. In this facility drying machines process waste paint and sludge, while crushers, condensing machines and grinding machines reprocess and recycle other waste materials. The plant also cleans and recycles more than 4,000 tonnes of waste water each day. The emission and energy consumption levels for the plant are exceptionally low for a unit of this type, helped by the use of solar power to provide energy and electricity to some buildings. These examples of environmental commitment were decisive in the attribution of the ISO14001 certification in 1998. The Kyushu plant was honoured with the J.D. Power Platinum World Award for product quality in 2001 and won the Gold Award for Asia in 2002. The quality of the end product of the plant, the new Lexus RX300, will of course speak for itself. LEXUS RX300: TECHNICAL GLOSSARY THREE-STAGE ACIS (ACOUSTIC CONTROL INDUCTION SYSTEM) The Lexus RX300’s 3.0-litre V6 powerplant of the Lexus RX300 is equipped with an innovative variable air intake system which adjusts the length of the intake manifold according to the engine’s load and speed. The purpose of ACIS is to improve torque throughout the rev range, particularly at low speeds. ACIS also promotes a smoother engine operation with three independent variation stages, compared to the two featured in most conventional systems. ACIS has been installed in the 1MZ-FE V6 engine since 1998. The stage variation is achieved through the control of two actuators (one in the throttle body, the other in the intake air chamber) by the engine ECU. These actuators selectively open and close to control the air intake route through the air cleaner hose, throttle body and intake air chamber. Stage 1 - heavy load, low-speed range To suit the longest cycle of intake pulsations (at lower engine speeds), the engine ECU closes both actuators. As a result, the air stream will take the longest route to the combustion chamber, passing through the air cleaner hose, throttle body and intake air chamber. Stage 2 - heavy load, mid-speed range To generate a suitable response in these conditions, ACIS will operate an intermediate stage, activating only the throttle body actuator. As a result, the intake air chamber will function as an intake manifold, shortening the intake air path compared to Stage 1. Stage 3 – during idling, light load and high-speed range To suit a very short cycle of intake pulsations, the two intake air control valves are opened, allowing a quicker air supply to the combustion chamber and improving volumetric efficiency. 4WD SYSTEM WITH CONTINUOUS TORQUE SPLIT The Lexus RX300’s full-time four-wheel drive system of Lexus RX300 constantly distributes torque at a 50:50 ratio between front and rear axles. Compared to that used on the first-generation RX300, the efficiency of this 4WD system has been improved to such a level that it doesn’t require a limited-slip differential mechanism for the centre differential or a viscous coupling-type LSD for the transfer mechanism. As a result, the whole system is much lighter and simpler, which also adds to overall reliability. Traction control versus limited-slip centre differential Thanks to improvements made to the TRC (traction control) system, the new RX300’s 4WD system can prove more efficient than the former LSD-based system in most driving conditions. For instance, in situations where both a front and a rear wheel are slipping, the centre differential would prove inefficient in providing a torque split that could be converted into traction. However, on a TRC-based system, the TRC would selectively brake these two wheels, forcing the differentials to transfer all the torque to the wheels with most grip. In addition, the TRC system is also quicker to react than an LSD mechanism, as the wheel sensors can detect even the slightest slippage. In practice, the RX300’s 4WD system equipped with TRC can provide continuous and instantaneous torque distribution to each wheel. ACTIVE CONTROL ENGINE MOUNT 
To achieve low levels of noise and vibration, the Lexus RX300’s front engine mount has been equipped with an active system, unique among vehicles in its segment and a world-first for Lexus when it was introduced in 1998. The Active Control Engine Mount operates during idling, at engine speeds below 900rpm. The engine ECU sends signals synchronised to the engine speed so that the engine vacuum can be utilised to vary the pressure of the intake air chamber in the Active Control Engine Mount. As a result, an internal diaphragm vibrates, and, using the liquid as a medium, the rubber mount vibrates. This vibration acts to cancel out engine vibration during idle, thus reducing overall noise and vibration levels. AIR SUSPENSION SYSTEM The Automatic Vehicle Height Control continuously adjusts the vehicle height to a predetermined level, independent of the number of passengers or load. The Air Suspension ECU receives information from four different vehicle height sensors and can command the system to fill or empty the pneumatic cylinders if any variation in ride height occurs. The Air Suspension System can also adjust the vehicle height according to several conditions:
The Vehicle Height Control can be activated using a switch in the centre console. This allows the driver to choose between three different height settings. On selecting Vehicle Speed Sensing Control, the vehicle’s height will automatically be lowered by 7.5mm from the normal mode for speeds above 62mph. However, if the vehicle height switch is set to HI and the vehicle speed is between 19 and 31mph, the Vehicle Height Control will transfer vehicle height to N (normal) mode after 10 seconds. If the speed happens to be higher than 31mph, the vehicle’s height will immediately be lowered to N mode. The Access Mode Control will lower the vehicle’s height to allow an easier access for passengers and loading or unloading of cargo. By pressing the Access Mode button, the vehicle’s height will be lowered by 25mm from N mode. A UTOMATIC LIGHT CONTROL SYSTEM The new Lexus RX300 is equipped with a system that automatically turns on headlights and taillights in poor light conditions. This system is particularly useful in daytime driving on roads with tunnel sequences.
The Customised Body Electronics System enables the settings of up to 40 electronic vehicle functions to be adjusted to suit each owner’s individual requirements. This task can be performed on request by all Lexus Centres. The range of features which can be customised include the remote locking system, theft deterrent system, electric windows, wipers, intelligent illuminated entry system, light control system, sunroof, air conditioning and power tailgate. THORAX-ABDOMEN-PELVIS (TAP) SIDE AIRBAG A
new generation of side airbags is being launched in the new Lexus RX300. They have a bigger capacity and so protect a wider area of the passenger’s body. Instead of protecting just part of the abdomen or torso, they can simultaneously protect the torso, abdomen and pelvis. To achieve this superior level of side-impact protection, these airbags have a capacity at least six litres greater than most others available on the market. The TAP side airbags are offered as standard equipment in the new RX300 and, complemented by the vehicle’s strong body construction and the curtain shield airbags, they provide top levels of injury protection in the event of side impacts. INTELLIGENT ADAPTIVE FRONT-LIGHTING SYSTEM (AFS) Introduced in the Lexus RX300 as a world-first for SUVs, Intelligent AFS can greatly improve levels of active safety during night-time driving. By swinging the projector headlight (low beam) to the inner side of the cornering direction, Intelligent AFS ensures a wider illumination area. The Intelligent AFS ECU receives information from the steering wheel angle sensor and speed sensor. This lets the system acknowledge the steering angle, steering direction and speed of the vehicle and calculate the ideal swivel angle for the projector beam.
In addition to Intelligent AFS, the Lexus RX300 also features xenon headlights with an Automatic Headlight Levelling System. INTELLIGENT ILLUMINATED ENTRY SYSTEM This system can control several different light sources in the interior in order to provide the passengers with the right type of illumination at the right time. The lighting sources are: interior light (roof), key illumination, scuff plate light, inside door handle light, footwell light and combination meter ring illumination. Each one is turned on and off in coordination with different actions, such as unlocking doors, opening and closing the driver’s door and turning the ignition on. This special illumination system and the combination of all light sources represent a step forward in convenience and add to the premium look of the RX300’s cabin. KNEE AIRBAG In a frontal collision, the 16-litre SRS knee airbag will inflate and protect the driver’s knees from hitting the lower parts of the dashboard. The knee airbag will also help keep the driver’s body in the correct position for optimum protection from the seatbelt and front airbag. The Lexus RX300 is the first SUV in the world to feature a knee airbag, fitted as standard. LED (LIGHT EMITTING DIODE) STOP LIGHTS In the new Lexus RX300, LED technology is used in the design of the stop lights. The replacement of the conventional light bulbs by LED lights achieves three distinct benefits: Safety: LED elements light up 10 times faster than lamp bulbs, 2 to 15 milliseconds as opposed to 150 to 200msec. This represents something like six metres of reaction time at 62mph – a distance that could be crucial in avoiding a collision. Fuel efficiency: LEDs use less energy than conventional filament bulbs. They account for up to a 0.8 per cent improvement in fuel consumption. Design: LEDs are more compact and give the design team more freedom when designing the rear lights. LEXUS PARKING ASSIST MONITOR The new Lexus RX300 is the first vehicle in its segment to be equipped with an optional parking auxiliary system which can make reverse parking manoeuvres simpler and safer. The system consists of a small rear-view camera discreetly installed in the handle of the tailgate. It transmits images to a seven-inch LCD centre display when reverse gear is selected. Special software can generate guiding lines on the screen to provide assistance. The television camera uses a wide-angle lens that can capture objects that are almost directly below the rear bumper. 
Display StatusThe Lexus Parking Assist Monitor can function in three different modes:
The guiding lines are generated by the camera’s ECU. It receives information from the steering wheel sensor and from a vehicle speed sensor to adapt the guiding lines to the different phases of the parking manoeuvre. Manual Assist Mode
(c) 
 
(b) 
Rear edge line of bumper 
  
(f) (d)
Serial (parallel) Parking Assist Mode (a) (b) 
 
(b)
 
(e) (d)
(f) 
(c)
(Some guiding lines are shown as in manual assist)
MARK LEVINSON® AUDIO SYSTEM The new Lexus RX300 SE-L is equipped with an audio system developed by Mark Levinson®, the world’s most exclusive audio systems specialist. The equipment designed by Mark Levinson® for Lexus is of the same exceptional quality as its world-renowned home entertainment systems. The specification of the Mark Levinson® audio system includes:
The quality of the RX300 cabin itself also contributes a great deal to the achievement of such superb sound quality. The interior of the car is well insulated, with a low level of ambient noise. Several components have a high level of rigidity and so eliminate unwelcome resonance. The audio system for models with leather interiors has been subjected to a specific tuning process in order to deliver all the desired sound qualities. MULTI-MODE AUTOMATIC TRANSMISSION For the first time, all versions of the Lexus RX300 are equipped with a five-speed automatic transmission. The system is designated as Multi-mode as it allows the driver to choose between automatic and sequential gear changes. Manual sequential shifts can be made by moving the gear lever to the “S” position. From there, gears can be selected by moving the shift lever forwards ("+" position) or backwards ("-" position). The gear selected is indicated in a display in the central instrument cluster. The five-speed automatic transaxle incorporates a number of other features:
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