282 282 Service. AUDI A8 ´03 - Technical Features Self Study Programme 282 All rights reserved. Subject to technical modification. Copyright* 2002 AUDI AG, Ingolstadt Department I/VK-35 D-85045 Ingolstadt Fax 0841/89-36367 000.2811.02.
Complete vehicle information The design and operation of the Audi A8 ´03 are described in the following Self Study Programmes: SSP 283 – 6-speed automatic gearbox 09E in the Audi A8 '03 - Part 1 SSP 284 – 6-speed automatic gearbox 09E in the Audi A8 '03 - Part 2 SSP 285 – Running gear in the Audi A8 '03 SSP 286 – New data bus systems - LIN, MOST, BluetoothTM SSP 287 – Audi A8 '03 - Electrical components SSP 288 – Audi A8 '03 - Distributed functions SSP 289 – Adaptive cruise control in the Audi A8 '03 SSP 2
Contents Page Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Passenger Protection System layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Safety systems . . . . . . . . . . . . . . . . .
Introduction Introduction The new Audi A8 is designed to replace its predecessor of the same name which achieved a total production figure of 105,092 since its introduction in June 1994. This was the first standard saloon with aluminium body and epitomised a new philosophy in the luxury vehicle sector. This body concept was further perfected in the Audi A2 and the design of the Audi A8 ´03 reflects the experience gained from both projects.
As the Audi flagship, the new Audi A8 is intended to symbolise the product identity of the next Audi generation. An uncompromising sporty character, clearcut design, innovative technological systems and the highest possible quality level combine to provide an unforgettable driving experience. In other words: Automatic boot lid opening and closing function (optional) Audi at its proverbial best.
Body 1444 Brief outline 976 1615 1894 2028 125 714 1629 971 2944 1136 5051 SSP282_026 Kerb weight 6 1,780 kg Turning circle 12 m Tank capacity approx. 90 litres Gross weight Luggage compartment volume Drag coefficient 2,380 kg approx. 500 l 0.
Body The Audi A8 ´03 sets new standards in its class by combining lightweight construction with outstanding stability. This is achieved through the use of innovative Audi Space Frame technology for the body design of the Audi A8. The technical progress reflected by the unique body concept stems from the consistent implementation of experience gained from the aluminium Audi A8 and A2 models.
Body A-pillar The A-pillar is made of two cast shells connected by rivets and welds. The shells enclose the sill panel at the bottom and the continuous roof frame at the top. SSP282_029 Sill panel Use is made for the sill panel of a 3-piece extruded section. The extruded section must be replaced in the event of sill panel damage. Depending on the nature of the damage, either the entire section has to be replaced or parts of it by way of three separating sleeves.
Rear end The rear end has been completely redeveloped. The two large central castings are the one connecting the sill panel/ longitudinal member and the C/D-pillar connecting element. The sill panel/longitudinal member connecting element is the largest casting. It supports the entire rear sub-frame and links the rear longitudinal member to the sill panel. Its great rigidity is designed to protect the tank in between in the event of a rear-end collision.
Body Boot lid Foam encasing Electronic boot lid lock with microswitch SSP282_035 Motor for automatic closing aid Bowden cable A standard feature is an automatic closing aid, which is actuated by a Bowden cable separately from the catch. After the latch has closed, a mechanism pulls the catch downwards, overcoming the build-up of pressure occurring. On locking, a microswitch in the boot lid lock transmits a signal to the control unit to activate the automatic closing aid.
Automatic boot lid Hinge mechanism (open) Boot lid control unit J605 Button in driver's door Button on boot lid Vehicle key SSP282_036 Pressing the button in the driver's door or on the boot lid, or remote control actuation, effects release and motor-driven opening of the boot lid. Automatic boot lid closing can only be implemented by way of the boot lid button.
Body Front doors The doors are made up of a combination of aluminium panels, aluminium sections and aluminium castings. Optimised rib geometry and wall thickness in the hinge and lock mounting castings formed the basis for ideal implementation of the lightweight construction concept. Door shell and door frame are connected at the door pre-assembly stage by means of fitted bolts to ensure the accurate assignment of both components.
Seats Backrest adjustment – The angle of the top 1/3 of the backrest can be adjusted by 15° for enhanced shoulder comfort. Lumbar support with massage function over a length of 60 mm Crash-active, electronic head restraint with 70 mm height adjustment Thorax/pelvis side airbag Backrest fan SSP282_116 Electric seat depth adjustment – As the structure moves forwards it pulls the padding with it and so extends the seat area by 50 mm. Seat cushion fan A new seat concept was developed for the Audi A8 ´03.
Passenger Protection System layout G 284 G 283 K145 AIRBAG J623 OFF J285/K75 AIRBAG E224 AUS EIN T16 J533 N95/G85 N131 J234 E24 E25 J526 N199 G179 N200 N154 N153 N201 N251 G180 N202 N196 N198 N252 N197 G 256 G 257 J393 J655 14 SSP282_068
Use is made in the Audi A8 ´03 of the 8.4E+ The wide range of sensors permits detection airbag system with the aim of attaining greater not only of head-on collision and side impact, occupant safety whilst reducing the impact. but also of rear-end collisions. This was achieved, for example, by way of twostage front airbag triggering, active front head restraints and a battery cut-off element.
Passenger Protection Block diagram 15 3 1 G283 G284 G179 J655 E224 2 J234 F138 N95 N131 N199 N200 N201 N202 Key E24 Driver side belt switch E25 Front passenger side belt switch E224 Airbag disabling key switch, front passenger side F138 Airbag coil connector/return spring with slip ring 16 G179 Side airbag crash sensor, driver side G180 Side airbag crash sensor, front passenger side G256 Rear side airbag crash sensor, driver side G257 Rear side airbag crash sensor, front passenger side G28
G180 G256 G257 E24 E25 4 N251 N252 N153 N154 N196 N198 5 6 7 N197 SSP282_069 Additional signals N251 Curtain airbag igniter, driver side N252 Curtain airbag igniter, front passenger side 1 Battery A (positive) 2 Positive connection to starter B and alternator C 3 Terminal 58s 4 Drive system CAN (High) 5 Drive system CAN (Low) 6 Crash signal 7 Airbag disabled warning lamp, front passenger side K145 Colour code = Input signal = Output signal = Positive supply = Earth 17
Passenger Protection Safety systems 2-stage front airbags The 2-stage triggering of the front airbags provides optimum restraint in crash situations at around 30 km/h. There is a separate firing pellet for each stage in the driver's and front passenger's airbag. These ignite successively at specified time intervals. Ring airbag SSP282_070 A so-called "ring airbag", which inflates like a life belt, is used on the driver's side.
Front passenger's airbag deactivation An optional feature of the Audi A8 ´03 is a new airbag disabling key switch for the front passenger's side E224. Two resistance paths are integrated into this switch to permit detection of individual faults. A fault in the key switch is indicated by flashing of the front passenger's side airbag disabled warning lamp K145 located in the centre console next to the hazard warning switch.
Passenger Protection Detection of rear-end collision Rear-end collisions are detected by way of a sensor in the airbag control unit J234 and a plausibility function involving the driver's and front passenger's front airbag crash sensors G283 and G284. Up-front sensors For the first time, use is made in the Audi A8 ´03 of so-called up-front sensors. These take the form of two additional frontend acceleration sensors on the right and left beneath the corresponding headlight.
Active head restraints The front seats of the Audi A8 ´03 are provided with active head restraints. With this system, the head restraints move forwards in the event of a rear-end collision to shorten the distance between head and restraint. The danger of cervical vertebrae injury is greatly diminished by reducing the relative acceleration between shoulder and head. In head-on collision situations, the mechanics of centrifugal weight are neutralised.
Passenger Protection Battery cut-off relay J655 The battery cut-off relay is a battery isolating element designed to disconnect starter and alternator power from the electrical system in the event of a crash. Terminal Pin Input/output Description 30, battery A Input (screw connection) Ubat. term.
Fitting location The battery cut-off relay is located in front of the battery. Triggering SSP282_083 The airbag control unit J234 provides the battery cut-off element with the triggering command via a discrete wire. Triggering of this element by the airbag control unit causes a white panel to appear in the element window instead of a copper coil. Following isolation, the battery cut-off element can be manually reset by way of the yellow knob.
Engine, Mechanics Technical data V8 4.2 l 5V engine 4,172 Bore: 84.5 mm Compression ratio: Power: Torque: 93.0 mm 11 : 1 246 kW (335 hp) at 6,500 rpm 430 Nm at 3,500 rpm Camshaft adjustment range: 22° CS advance Valves: 5 per cylinder Engine management: ME7.1.1 Emission standard: EU 4 Firing order: 1-5-4-8-6-3-7-2 Capacities: 7.5 l engine oil (incl. filter) Consumption: Urban: 17.5 - 17.6 l/100 km Non-urban: 8.7 - 8.8 l/100 km Average: 11.9 - 12.
BFL Capacity: 3,697 cm3 Bore: 84.5 mm Stroke: Compression ratio: Power: Torque: 82.4 mm 11 : 1 206 kW (280 hp) at 6,000 rpm 360 Nm at 3,750 rpm Camshaft adjustment range: 13° CS advance Valves: 5 per cylinder Engine management: ME7.1.1 Emission standard: EU 4 Firing order: 1-5-4-8-6-3-7-2 Capacities: 7.5 l engine oil (incl. filter) Consumption: Urban: 17.1 - 17.3 l/100 km Non-urban: 8.6 - 8.8 l/100 km Average: 11.7 - 11.
Engine, Mechanics V8 5V 3.7 l/4.2 l engine The 3.7 l and 4.2 l V8 engines were adopted from the predecessor model with certain modifications. Design and operation are described in SSP 217. These modifications relate to the intake and exhaust systems and are described in the following. Variable-intake manifold in 4.2 l engine This takes the form of a 2-stage variable-intake manifold made of a die-cast magnesium alloy, bonded and bolted together in four sections.
– Long intake path, 705 mm – Changeover flap closed for high torque SSP282_014 Each of the two splined shafts is fitted with four flaps per cylinder bank. The shape of the rubber-encased flaps ensures unimpeded air flow in the torque position and reliable power position sealing of the duct. This is a prerequisite for utilisation of the gas-dynamic resonance effects.
Engine, Mechanics Variable-intake manifold in 3.7 l engine Changeover flap, stage 3 Intake air (inlet) t nic o ctr e ele valv m e Fro rottl Th Vacuum unit Changeover flap, stage 3 o hr ttl e Injector mounts Changeover flap, stage 2 (open) Vacuum unit Changeover flap, stage 2 Resonance tube, cyl. 5 (inlet end) This is the same 3-stage variable-intake manifold as previously fitted in the V8 engine. Due to the piston stroke of only 82.
Air cleaner A round filter is employed instead of a flat filter to achieve a larger filter surface area for more air throughput in view of the different amount of space available. SSP282_018 Furthermore, an additional intake air flap in the air cleaner is opened as a function of load at engine speeds as of 3,000 rpm to attain the large volume of air required at full throttle. This flap enables additional air to be drawn in from the engine compartment and reduces the air velocity in the air cleaner.
Engine, Mechanics Fuel pump relay J17 Fuel pump G6 System layout Fuel pump II relay J49 Fuel pump G23 Actuators/sensors Engine control unit J623 Hot-film air-mass meter G70 Engine speed sender G28 Injectors N30, N31, N32, N33 (bank 1) Hall sender G40 (bank 2) and Hall sender 2 G163 (bank 1) Lambda probe G39 (bank 1) Lambda probe II G108 (bank 2) Lambda probe after catalyst G130 (bank 1) Lambda probe II after catalyst G131 (bank 2) Pedal position sender/accelerator pedal module with accelerator pedal
Engine, Mechanics Fuel pump relay J17 Fuel pump G6 System layout Fuel pump II relay J49 Fuel pump G23 Actuators/sensors Engine control unit J623 Hot-film air-mass meter G70 Engine speed sender G28 Injectors N30, N31, N32, N33 (bank 1) Hall sender G40 (bank 2) and Hall sender 2 G163 (bank 1) Lambda probe G39 (bank 1) Lambda probe II G108 (bank 2) Lambda probe after catalyst G130 (bank 1) Lambda probe II after catalyst G131 (bank 2) Pedal position sender/accelerator pedal module with accelerator pedal
Engine, Mechanics Electrohydraulic torque reaction support Stress-free alignment of the torque reaction support is implemented by way of the lock nut. Lock nut Isolation diaphragm Shell Upper section of nozzle plate Top section Plastic ring with sheet metal ring Connecting pipe Solenoid Bellows cap SSP282_020 Bottom section The purpose of torque reaction support is to cushion the drive shaft and propshaft torque.
Exhaust system Exhaust manifold Lambda probe G39, cylinder bank 1 Two-stage catalytic converter Lambda probe after catalyst G130 Connecting pipe Lambda probe II G108, cylinder bank 2 Lambda probe II after catalyst G131 SSP282_028 With the 4.2 l and 3.7 l engines, the exhaust system is of the dual-flow type.
Engine, Mechanics Fuel tank The fuel tank capacity is approximately 90 litres. The basic unit consists of two plasma-welded stainless steel shells. There are no differences between petrol and diesel engine versions. The tubing system for the tank breather at the filler pipe has been considerably simplified as compared to the predecessor model. With the exception of diesel vehicles, the pipe connections have been converted to quickrelease couplings.
Interior of fuel tank (filling) Float-type shutoff valve Filler pipe Breather pipe to filler pipe Reservoir with pump unit, right Reservoir with pump unit, left Baffle housing of expansion tank SSP282_006 Overflow channel The fuel is conveyed via the filler pipe into the right tank chamber (as viewed in direction of travel). The fuel passes via an additional overflow channel at the end of the filler pipe predominantly into the right pump reservoir.
Engine, Mechanics Expansion tank Inlet pipe from tank filler neck Float-type rollover valve Breather pipe Suction jet pump intake connection Float-type shutoff valve SSP282_009 The expansion tank (capacity approx. 2 litres) consists of a plastic housing clipped to the upper shell of the tank. The internal expansion tank houses a floattype rollover valve and a small suction jet pump which constantly pumps the tank empty whilst driving.
Two-stage fuel pumps Main stage delivery end Main stage suction end Return Overflow Reservoir Main stage pump unit Pre-stage pump unit Pre-stage suction end Pre-stage delivery end Fuel tank Main stage suction end SSP282_003 The two fuel pumps (petrol engine) are of the two-stage flow type. The first stage (pre-stage) pump unit draws in fuel from the bottom of the tank and conveys it into the reservoir. This ensures that even small residual quantities can be transported.
Engine, Mechanics Fuel system (hydraulics) Pressure regulator (4 bar) Fuel pump G23 Fuel pump G6 Suction jet pump When the ignition is switched on (terminal 15), the fuel pump G23 conveys a maximum volume to the pressure regulator at the fuel rail to achieve short starting times. The pump G6 also conveys fuel to the pressure regulator and additionally into the pipes for the two suction jet pumps in the side tank compartments.
Tank senders Magnetically soft foil The fuel level is sensed by two immersion tube senders and two angle senders. A new feature is the design of the angle sender, which is equipped with a magnetically passive position sensor. The ceramic substrate is provided with 51 series-connected film resistors with individual pick-off. Fitted with a small clearance on top of this is a magnetically soft foil with the same number of spring contacts.
Engine, Mechanics Determining fuel level b c a SSP282_004 The fuel level is determined by way of a logical system of immersion tube and angle sender signals. The sender signals are evaluated by the dash panel insert. All senders are connected in parallel. a - Low levels are determined exclusively by way of the angle sender measured values The wires are bunched beneath the fuel tank, thus enabling resistance measurements to be taken without the need for further dismantling.
Automatically controlled starting The automatic start control is integrated into the engine control unit. A new feature is that starter control is no longer implemented by way of the ignition/ starter switch D (switching of terminal 50), but rather it is performed automatically by the engine control unit. Release for starter actuation is always transmitted by the entry and start authorisation control unit J518 to the engine control unit J623.
Engine, Mechanics Sequence of operations 1 Entry and start authorisation switch E415/ entry and start authorisation button E408 The driver triggers a brief start signal (min. 20 ms) by turning the ignition key to start position or by pressing the entry and start authorisation button E408.
Block diagram E415 N376 D1 E408 2 1 0 STOP 1 6x 2 1 0 START 2 58s J518 50R 15 1 2 75x 30 50R 3 J623 J329 D1 E408 E415 J53 J329 J518 J694 J53 Inhibitor reading unit Entry and start authorisation button Entry and start authorisation switch Starter motor relay Terminal 15 voltage supply relay Entry and start authorisation control unit J695 J623 J694 J695 N376 SSP282_024 Engine control unit Terminal 75x voltage supply relay Starter relay 2 Ignition key withdrawal lock magnet Additional si
Engine, Mechanics Explanatory notes on internal control unit sequence chart Request for starting (terminal 50 ON from entry and start authorisation control unit J518) energises the two relays. Locking-in takes place during the initialisation phase of engine control unit J623. After initialisation, the engine control unit assumes further starter control tasks as described under item 3. Term.
Gearbox To satisfy high comfort requirements, the Audi A8 ´03 features a new 6-speed automatic gearbox capable of handling a high engine torque of max. 600 Nm. Two different versions are available: – 420 Nm for the V8 5V 4.2 l or 3.7 l engine and – 600 Nm for the V8 TDI 4.0 l or 6.0 l W12 engine Design and operation of the 09E gearbox are described in SSP 283 (Part 1) and SSP 284 (Part 2). SSP282_043 Technical data Designation: Factory designation: ZF designation: Type: Control: 09E Max.
Gearbox Highlights of automatic gearbox 09E (AL 600-6Q) The 6-speed planetary gearbox is based on the Lepelletier principle. This concept is characterised by harmonic gear ratio steps and the implementation of six forward gears and one reverse gear with only five selector elements. SSP282_044 Use is made in this gearbox of a new internal gear oil pump featuring a lower delivery volume and reduced leakage.
The mechatronic system integrated into the gearbox housing is a new development, combining the hydraulic control unit, sensors, actuators and electronic gearbox control unit in a coordinated assembly. All data exchange with the vehicle periphery takes place via the drive system CAN, thus reducing the number of vehicle periphery interfaces to a minimum (11 pins) and at the same time enhancing operational reliability.
Gearbox In terms of the following functions, there are interesting new aspects to the shift mechanism in the new Audi A8 '03: – – – – – Shift mechanism kinematics Ignition key removal lock Selector lever lock Selector lever lock emergency release Selector lever/lock button kinematics Ignition key removal lock Selector lever/button kinematics Major modifications have been made to operation of the ignition key removal lock and selector lever lock (shiftlock).
Running Gear Front axle The familiar four-link front axle was retained for the Audi A8 '03. A significant new feature is the air suspension in combination with electronically controlled dampers (refer to Section on air suspension). All axle components are new on account of the geometric and kinematic modifications as compared to the predecessor model, the air suspension and the weight reductions achieved.
Running Gear Rear axle The rear axle is a more advanced version of the familiar Audi A8 trapezium-link axle. All axle components are new on account of the geometric and kinematic modifications as compared to the predecessor model, the air suspension and the weight reductions achieved.
4-level air suspension The introduction of the Audi A8 ´03 is accompanied by a system featuring new technical details and functions. The major differences with respect to the familiar Audi allroad quattro® system are as follows: EDC instead of PDC damping The control system makes allowance for the currently applicable driving status. Wheel movement (unsprung masses) and body movement (sprung masses) are detected.
Running Gear System layout Rear axle acceleration sensors Control unit with display in dash panel insert J285 Front information and display and operating unit control unit J685 Rear axle air suspension struts Pressure accumulator Adaptive suspension control unit Front axle air suspension struts SSP282_054 Rear axle level sensors Front axle level sensors Solenoid valve block Compressor Front axle acceleration sensors Design and operation of 4-level air suspension are described in SSP 292.
Electric parking brake The brake pads are applied by way of a spindle mechanism. The following functions are provided by the electric parking brake: Gear unit and motor are flanged to the brake caliper. – – – – Implementation of the parking brake function involves translating the rotation of the drive motor into a very short brake piston stroke. This is achieved through the use of a swash plate mechanism in combination with the spindle mechanism.
Running Gear ACC (Adaptive Cruise Control) Adaptive Cruise Control is a new system designed to assist drivers and offers a much wider range of functions than the conventional Tempomat. Driver convenience is further enhanced, as fewer accelerator and brake pedal operations are required. Speed restrictions and safety factors are reliably observed and the flow of traffic thus better regulated.
ACC system limits Radar sensor – ACC is designed to assist the driver and is not a safety system. – ACC is not a fully autonomous driving system. – ACC provides control in a speed range of 30 - 200 km/h. – ACC does not react to stationary objects. – Radar operation is impaired by rain, spray and slush. – Tight bends may restrict operation on account of the limited radar detection range. An adapter plate permits fitting and adjustment at a holder bolted to the centre of the bumper bracket.
Running Gear Setting desired speed The desired speed is the maximum speed to be controlled by the ACC on an open road (corresponds to cruise control system function). Pressing the SET button stores the current speed as desired speed. SSP282_061 The set speed is displayed by a bright red LED in the speedometer rim and the "ACC active" symbol appears in the speedometer. The "ACC active" status is indicated by faint red illumination of all LEDs in the range between 30 and 200 km/h.
Setting desired distance The desired distance from the vehicle in front can be set by the driver in four stages. The distance set by the ACC is governed by the respective vehicle speed. The distance increases with increasing vehicle speed. The minimum setting ensures compliance with the permissible safety distance when travelling at a constant speed in traffic. The desired distance from the vehicle in front is set by means of the sliding switch on the stalk.
Electrical System Bus topology Distance regulation control unit J428 Dash panel insert CAN Adaptive cruise control CAN The increasing demand for additional functions and convenience in the vehicle calls for the use of ever more wide ranging electronics. The increased use of electronics also requires a new approach to data transfer between the individual control units. This also applies to the Audi A8 ´03, in which more than 70 control units have to communicate.
Rear DVD changer R162 Telephone/ telematics control unit J526 Control unit for rear right information display and operating unit J649 BluetoothTM Telephone handset R37 Control unit for rear left information display and operating unit J648 Front information display and operating unit control unit J523 DSP control unit J525 Data bus diagnostic interface J533 Navigation system control unit J401 MOST bus CD ROM drive R92 TV tuner R78 CD changer R41 Digital radio R147 Chip card reader control unit
Electrical System The familiar CAN bus (two-wire bus) is supplemented by the following bus systems: – LIN bus (single-wire data bus) – MOST bus (optical data bus) – BluetoothTM (wireless data bus) LIN bus LIN stands for Local Interconnect Network. Local Interconnect means that all control units are located within a limited structural space (e.g. roof). This is also referred to as "local sub-system".
MOST bus The term "Media Oriented Systems Transport" signifies a network featuring media-oriented data transport. This means that, in contrast to the CAN data bus, address-oriented messages are transmitted to a specific receiver. R Media Oriented Systems Transport This technique is used in Audi vehicles for the transfer of infotainment system data. The infotainment system offers a wide range of modern information and entertainment media.
Electrical System BluetoothTM BluetoothTM is an internationally standardised remote control data interface. It permits control or monitoring of even minute units using radio waves. The primary aim when developing this new type of interface was to create a wireless alternative to cable links, which used to be susceptible to interference and inconvenient and frequently featured incompatible connectors.
Vehicle electrical system A major factor in terms of vehicle reliability is one which is never even seen: the electrical system. Use is made for the Audi A8 ´03 of a customerspecific one-piece modular wiring harness. "One-piece" means that power is supplied for all essential electrical functions from a single continuous wiring harness. The only isolating points are at the doors, roof module and engine.
Electrical System Convenience and security electronics "Advanced Key" entry and start authorisation system "Advanced Key" can be taken to mean an "advanced locking and security system". It takes the form of a non-contacting key recognition system. With the "Advanced Key" package, the "Vehicle unlocking" and "Vehicle locking" functions by way of a mechanical or remote control key are supplemented by the noncontacting functions "Vehicle unlocking" and "Vehicle locking".
Multifunction steering wheel A new multifunction steering wheel has been introduced as standard. This is equipped with special paddles (as used in formula 1 and for the Le Mans R8) for manual shifting of the 6-speed Tiptronic®. The voice control option for radio, CD changer, telephone, navigation system and MMI address book can also be operated by way of the multifunction steering wheel.
Electrical System Infotainment DVD - Video DAB - Digital radio Telephone Telematics Central display and control TV reception CD/DVD navigation Internet Email Minidisc/CD audio Both in the modern business world and in the private domain, mobile information and entertainment are becoming ever more important. 66 SSP282_090 In other words, vehicle occupants are becoming increasingly interested in enjoying the benefits of modern media.
With this in mind, the Audi A8 ´03 is fitted with an infotainment system offering a wide range of modern media. Memory CD 1 Source Dire Straits - Brothers in … Forward Tr. 12 10:56 Manual TP TMC D2 Private Sound SSP282_096 Design and operation are described in SSP 293 - Audi A8 ´03 Infotainment.
Electrical System Lighting system Front lights Parking light (W5W/5 W bulb) Adaptive light (H8/35 W bulb) Turn signal indicator (2 x 16 W HPV bulb - yellow) SSP282_056 Additional main beam Headlight flasher (H7/55 W bulb) Reflector for adaptive light The headlight in the Audi A8 ´03 combines both design elements and innovative technology.
The optional headlights with adaptive light function are a clearly visible innovative feature in the Audi A8 ´03. To implement this function, the headlights are provided with an additional reflector between dipped beam and main beam. SSP282_092 Light functions Adaptive light SSP282_087 Adaptive light The additional reflector with a 35 W H8 halogen bulb is actuated as the situation requires to ensure earlier perception of other road users or obstacles.
Electrical System Assistant lighting system This system adapts the vehicle lighting to the prevailing light conditions. For this purpose the light switch must be set to AUTO. The rain and light detector sensor G397 establishes the prevailing light conditions and activates the vehicle lighting system if appropriate.
Rear lights Brake/tail light on boot lid – Red LEDs Brake/tail light on side panel – Red LEDs Rear fog light – 16 W HPV bulb Turn signal indicator – Yellow LEDs Reversing light – 16 W HPV bulb SSP282_089 Reflector The newly designed rear lights are an ideal combination of design, function and ultramodern technology. Light-emitting diodes are used for the tail light, brake light and turn signal indicator functions.
Heating/Air Conditioner Design and operation The air conditioning system represents a more advanced version of the concept employed in the Audi A8 predecessor model with 2-zone climate control and features fully automatic regulation. An optional feature for the Audi A8 ´03 is 4-zone climate control, enabling both driver and all passengers to make individual settings independently of the climate control level selected for the other occupants.
Heating/Air Conditioner Operating principle When the ignition is switched on, the Climatronic control unit J255 starts up with the same temperature, air distribution and fresh-air blower speed settings etc. as were applicable the last time the ignition was switched off by way of the appropriate key or using fingerprint recognition. If fingerprint recognition has been implemented, this has priority over key recognition (refer also to SSP 287 – Audi A8 ´03 Electrical Components).
Climatronic control unit J255 Air conditioner defrost and electrically heated windscreen Reset to basic setting/ automatic mode Seat heating control Blower control Driver's side control panel Temperature sensor with blower Passenger's side control panel Left rotary control/pushbutton Rotary control +/- for – Temperature – Blower speed – Air distribution up/down – Seat heating – Seat ventilation – Menu control via MMI Pushbutton – Synchronisation of driver's side, passenger's side and rear settings Ai
Air conditioning system control via MMI All air conditioning system set values and basic settings (setup) can be displayed by way of the MMI. This applies both to the Climatronic control unit button functions and to setup. Distribution AC - driver Seat ventilation 3 21,5° C If the air conditioning system is activated with the MMI switched on, the air conditioner function settings can be called up and altered by way of the multimedia control panel.
Heating/Air Conditioner Blower unit/air routing As opposed to the predecessor model, the air conditioner features an additional evaporator outflow temperature sender G263. This is installed in the air duct downstream of the evaporator and constantly transmits the air temperature downstream of the evaporator to the Climatronic control unit J255. When replacing control motors, attention must be paid to the assignment of the flaps in the cam plate guides.
Recirculated-air flap Fresh-air/air-flow flap G263 Defrost flap V71 Right vent G151 V113 Indirect ventilation/left V107 V199 Left vent Indirect ventilation/ right G150 Right footwell flap V200 V68 Rear right footwell flap V219 Left footwell flap V108 Cold-air flap/ centre vent V102 V218 Rear left footwell flap Centre chest vent temperature/ warm-air flap Rear right warm-air flap (4-zone system only) Rear left cold-air flap (4-zone system only) Rear left warm-air flap (4-zone system only) Rea
Heating/Air Conditioner Electric rear additional heater An electric rear additional heater is fitted under each front seat in the rear climate control footwell air ducts. Operation Following a cold start or at low ambient temperatures, there is insufficient waste heat in the coolant to warm the rear of the vehicle by means of a conventional fluid-filled heater. In addition, the drop in temperature in the rear air duct is extremely high in the initial phase.
Notes 79
Heating/Air Conditioner System layout Control unit with display in dash panel insert J285 Front information display and operating unit control unit J523 Front information and display and operating unit control unit J685 MOST bus Fresh-air intake duct temperature sensor G89 Diagnosis CAN Radiator fan control unit J293 Data bus diagnostic interface J533 Flap control motor potentiometers G92, G113, G135, G136, G137, G138, G139, G140, G143, G317, G318, G349, G350, G351, G352 Engine control unit J623 Driv
Heating/Air Conditioner System layout Control unit with display in dash panel insert J285 Front information display and operating unit control unit J523 Front information and display and operating unit control unit J685 MOST bus Fresh-air intake duct temperature sensor G89 Diagnosis CAN Radiator fan control unit J293 Data bus diagnostic interface J533 Flap control motor potentiometers G92, G113, G135, G136, G137, G138, G139, G140, G143, G317, G318, G349, G350, G351, G352 Engine control unit J623 Driv
Heating/Air Conditioner Humidity sender G355 SSP282_104 At low ambient temperatures, when the windscreen is extremely cold, the top third is particularly susceptible to fogging. To cover this area, the humidity sender G355 is fitted in front of the base of the rear view mirror.
Operation Measurement is performed by way of a special capacitor which can absorb water vapour. The water absorbed produces a change in the electrical properties and thus the capacitance of the capacitor. The capacitance measurement thus provides information on the humidity level. The sender electronics convert the measured capacitance into a voltage signal.
Heating/Air Conditioner Climate-controlled seats with heating and ventilation function The Audi A8 ´03 can be fitted with front and rear climate-controlled seats as optional equipment. These seats offer a combination of seat heating and seat ventilation and can be regulated individually for each occupant. The buttons for the seat heating and ventilation options are integrated into the front and rear control and display units (refer to Page 74).
Comfort seat Backrest carbon heating mats Fan in backrest Side bolster carbon heating mat SSP282_108 Air ducts in seat padding Fan in seat cushion Seat cushion carbon heating mats Seat climate control is achieved by way of integrated fans in the seat cushion and backrest. Air ducts in the seat padding convey the air warmed by the seat heating to the occupant through the fine perforations in the leather.
Heating/Air Conditioner Block diagram for front air conditioner Key C20 Solar cells G56 G65 G89 Dash panel temperature sensor High-pressure sender Fresh-air intake duct temperature sensor Temperature flap control motor potentiometer Sunlight penetration photosensor Air-flow flap control motor potentiometer Defrost flap control motor potentiometer Left central vent control motor potentiometer Right central vent control motor potentiometer Central vent control motor potentiometer Left footwell flap control
15 30 75 3 C20 S S S 1 75 S S 2 5A 15A 20A 25A 25A Z45 V50 N175 N176 G238 G65 G107 G348 Z43 G347 Z42 J126 G191 M G344 Z46 N340 G345 G355 T16 V2 M J533 J528 58S V42 58S G56 J255 M 4 S 10A M V113 G143 V71 M M M M M M G113 V107 G135 V200 G318 V199 G317 V108 G139 V109 G140 V68 M M M M M M G92 V102 G138 V220 G351 V110 G136 V111 G137 V221 G352 G263 G151 G150 G89 N280 31 30 SSP282_109 in Colour code = Input signal = Output signal = Positive supply = E
Heating/Air Conditioner Block diagram for rear air conditioner 75 G177 Z10 G94 Z11 30 75 V273 V271 M G178 M S 20A 5A J674 J675 E265 S S M 5A G427 G426 15 30 88 S M V218 G349 V219 G350 in G95 S S 5A 20A Z12 out J533 15A 30 31 T16
Key Z13 E265 Rear Climatronic control and display unit G94 G95 G177 G178 Rear left seat temperature sensor Rear right seat temperature sensor Driver side rear seat occupied sensor Front passenger side rear seat occupied sensor Positioning motor potentiometer for rear left vent Positioning motor potentiometer for rear right vent Driver side rear seat temperature sensor Passenger side rear seat temperature sensor V272 V270 M M G349 G350 G426 G427 SSP282_115 J533 J674 J675 T16 16-pin connector (dia
Heating/Air Conditioner Auxiliary heater/coolant additional heater An auxiliary heater is available as an option for all vehicle and engine versions. The auxiliary heater with petrol engines and additional heater with diesel engines are integrated into the engine coolant circuit. Vehicles with diesel engine are fitted with an additional heater as standard. On diesel engines with auxiliary heater, the activated auxiliary heater is also used as engine additional heater depending on temperature.
4.2 Auxiliary heating sequence The level of fuel in the tank is interrogated. If the fuel tank is "empty", the auxiliary heating function is not permitted and the auxiliary heater symbol in the dash panel insert goes out. "Empty" roughly corresponds to the red display zone. The energy management control unit J644 checks whether there is sufficient energy to accept auxiliary heating.
Heating/Air Conditioner Small coolant circuit with auxiliary heater The small coolant circuit employed with auxiliary heating is designed to ensure rapid warming of the passenger compartment. Design and operation are described in SSP 267 – The 6.0 l W12 engine in the Audi A8 - Part 1. With the engine stopped, the coolant shutoff valve N279 switches to the small heating circuit until a defined temperature value has been attained.
Notes 93
Notes 94
282 282 Service. AUDI A8 ´03 - Technical Features Self Study Programme 282 All rights reserved. Subject to technical modification. Copyright* 2002 AUDI AG, Ingolstadt Department I/VK-35 D-85045 Ingolstadt Fax 0841/89-36367 000.2811.02.
