210 - E-GAS - Electronic Throttle - VolksPage.Net

Service.Self-Study Programme 210Electronic Power ControlDesign and Function

With the Electronic Power Control system, thethrottle valve is actuated only by an electricmotor.This eliminates the need for a Bowden cablebetween the accelerator pedal and the throttlevalve.By positioning the throttle valve, the engine controlunit can regulate engine torque even if thedriver has not depressed the accelerator pedal.The result is better co-ordination between andwithin the engine management systems.It means that the driver input is relayed to theengine control unit via the accelerator pedal.The engine control unit then sends a correspondingcommand to the throttle valve positioner.We will now demonstrate that the Electronic Power Control is more than just a substitute for the Bowdenaccelerator cable.NewImportantNote2The Self-Study Programmeis not a Workshop Manual.Please always refer to the relevant Service Literaturefor all inspection, adjustment and repair instructions.Service literature.

Table of contentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Throttle valve positioning . . . . . . . . . . . . . . . . . . . . . . . . 4System description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Control process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6System design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7What happens and when? . . . . . . . . . . . . . . . . . . . . . . 8System components . . . . . . . . . . . . . . . . . . . . . . . . . . 10System overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10The engine control unit . . . . . . . . . . . . . . . . . . . . . . . . . 11The accelerator pedal module . . . . . . . . . . . . . . . . . . 14The throttle valve control unit . . . . . . . . . . . . . . . . . . . 16The fault indicator lamp . . . . . . . . . . . . . . . . . . . . . . . . 22Auxiliary signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Function diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Self-diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Test your knowledge . . . . . . . . . . . . . . . . . . . . . . . . . 303

IntroductionThrottle valve positioning210_008Mechanical throttle valve positioning systemWith this system, the driver depresses the acceleratorpedal and thus positions the throttle valvemechanically by means of a Bowden cable.When the driver depresses the acceleratorpedal, the engine management system cannotcontrol the position of the throttle valve.To regulate engine torque, the engine managementsystem must refer to other controlledvariables such as ignition timing and injectiontiming.Throttle valve positioning by an electric motordrive is only possible in the idling speed rangeand in combination with the Volkswagen cruisecontrol system.Electric throttle valve positioning system210_007With this system, the throttle valve is positionedby an electric motor across the full adjustmentrange.The driver depresses the accelerator pedalaccording to the engine power required. Sendersregister the accelerator pedal position and relaythis information to the engine control unit. Theengine control unit now sends a signal correspondingto the driver input to the throttle valvepositioner which in turn sets the throttle valve tothe appropriate angle.If the engine torque has to be adjusted for reasonsof safety or fuel consumption, however, theengine control unit can adjust the position of thethrottle valve independent of the acceleratorpedal position.The advantage of this is that the control unitdefines the position of the throttle valveaccording to the various individual requirements(driver input, exhaust emissions, fuel consumptionand safety).4

System descriptionInternalrequirementsExternalrequirementsEnginecontrol unitOptimalefficiency210_009The "tools“ which the engine management system uses to influence the engine torque are:throttle valve, charge pressure, injection timing, cylinder suppression and ignition advance angle.Engine torque control withmechanical throttle valve positioningThe various torque requirements are signalledindividually to the engine control unit and thenprocessed.The torque demands cannot be matched optimallybecause the engine control unit cannotaccess the mechanically adjustable throttle valvedirectly.Engine torque control withelectric throttle valve positioningThis system permits torque-orientedengine management.Internal torque demands include:- Start- Catalytic converter heating- Idle speed control- Power limitation- Speed limiting device- Lambda controlExternal torque demands originate from:- the automatic gearbox (shift point)- the brake system (Traction Control System,engine braking control)- the air conditioning system(air conditioner compressor ON/OFF) and- the cruise control systemWhat does this mean?First, the engine control unit gathers all theinternal and external torque demands. Then itcalculates the necessary control actions.This system is more precise and efficient than theprevious system.5

IntroductionControl processThe engine management system generates aspecific torque according to the external andinternal torque demands.Actual torque is calculated from the followingfactors: engine speed, load signal and ignitionadvance angle.The engine control unit initially compares theactual torque and the specified torque. If thesetwo values differ from one another, the systemdetermines the corrective action necessary tomake these values match.The system pursues two lines of approach simultaneously.Engine control unit1st line of approach2nd line of approachSpecifictorque210_010Air flow rateActualtorqueIgnition,fuel injectionWith the first line of approach, the system activatesthe controlled variables that affect charge.These variables are also known as controlledvariables for long-term torque demand.They are:- throttle valve angle and- charge pressure (turbocharged engines).With the second line of approach, the systemchanges the controlled variables that affectshort-term torque independent of charge.They are:- ignition point,- injection time and- cylinder suppression.On the following pages, we will show you how the electric throttle valve positioning functionworks.6

System designElectronic Power Control comprises:- the accelerator pedal module together with the accelerator position senders,- the engine control unit,- the throttle valve control unit, and- the fault indicator lamp for Electronic Power Control.The accelerator pedal moduleAccelerator pedal moduledetermines the current accelerator pedal positionwith its senders and sends a correspondingsignal to the engine control unit.The engine control unitAuxiliary signalscalculates from this signal how much enginepower is required by the driver and converts thisinformation into an engine torque value. For thispurpose, the engine control unit activates thethrottle valve drive in order to open or close thethrottle valve further. When activating the throttlevalve drive, the engine control unit makes allowancefor additional engine torque demandfactors such as air-conditioning.In addition, it monitors the"Electronic Power Control” function.The throttle valve control unitis responsible for providing the required air massflow.The throttle valve drive actuates the throttle valvein accordance with the instructions issued by theengine control unit.The throttle valve angle senders supply theengine control unit with feedback on the positionof the throttle valve.Throttle valve control unitThe fault indicator lamp for Electronic PowerControl210_011Fault indicator lampindicates to the driver that there is a fault in theElectronic Power Control system.7

IntroductionWhat happens and when?In idling modeThe engine control unit can recognise from thesignal voltages of the accelerator position senderthat the accelerator pedal is not depressed.The idle speed control process now commences.Enginecontrol unitThrottle valvecontrol unitAccelerator pedal moduleAccelerator positionsender210_019The engine control unit activates the throttlevalve drive and positions the throttle valve bymeans of an electric motor.The throttle valve is opened or closed furtherdepending on the extent to which the actualidling speed deviates from the specified idlingspeed.Throttle valvedrive210_060The two angle senders for throttle valve drive signalthe current position of the throttle valve to theengine control unit.They are located in the throttle valve control unit.Angle sender forthrottle valve drive210_061The digital idling stabilisation function also supports the idle speed control process.8

Pressing the accelerator pedalThe engine control unit can recognise from thesignal voltages of the accelerator position senderthe extent to which the accelerator pedal isdepressed. Using this information, the enginecontrol unit calculates the driver input and positionsthe throttle valve by actuating the throttlevalve drive by means of an electric motor.The engine control unit also controls the ignitiontiming, the injection timing and, if necessary, thecharge pressure.210_021The two angle senders for throttle valve drivedetermine the throttle valve position and send acorresponding signal to the engine control unit210_062TC Air EBCThe engine control unit makes allowance foradditional engine torque demand factors whencalculating the necessary throttle valve position.These include:- the speed limiting device- the cruise control system- the Traction Control System (TCS) and- the engine braking control (EBC)210_063When engine torque is required, the throttlevalve can be adjusted even if the driver has notchanged the accelerator pedal position.9

System componentsSystem overviewSensorsEngine control unit J...ActuatorsAccelerator pedal module withaccelerator pedal positionsender -1- G79 andaccelerator pedal positionsender -2- G185Throttle valve control unitJ338Throttle valve drive G186Throttle valve control unit J338withangle sender 1for throttle valve drive G187andangle sender 2for throttle valve drive G188Fault indicator lamp forelectric throttle controlK132(Electronic Power Control)Clutch pedal switch F36Brake light switch Fandbrake pedal switch F47The system componentsmay be different to thoseshown in this overviewdepending on vehicleequipment specification.Auxiliary signals from:- automatic gearbox,- brake system,- air conditioning system,- cruise control system,and others210_037Diagnostic connection10

Engine control unit J...Its tasks in the Electronic Power Control:210_031The EPC calculates from the input signal suppliedby the accelerator position sender how muchengine power the driver requires and convertsthis information into an engine torque by meansof the actuators.The engine control unit makes allowance foradditional functions of the engine managementsystem (e.g. engine speed limitation, road speedlimitation and power limitation) and other vehiclesystems (e.g. the brake system or the automaticgearbox).The engine control unit also monitors the"Electronic Power Control“ system in order toprevent malfunctions occurring.DesignPut in simple terms, the engine control unit comprisestwo processing units:the function processor andthe watchdog processor.- The function processorFunction processorWatchdog processor210_012receives the signals from the sensors,processes them and then activates theactuators.The function processor also checks thewatchdog processor.- The watchdog processorserves only to check the function processor.11

System componentsMonitoring functionThe watchdog processor continuously monitorsthe functions of the function processor.At the same time, it checks the output signals ofthe function processor against its own calculations.The function processor and the watchdogprocessor check each other by means of a query& answer function.If faults are found, both processors can influencethe throttle valve control unit, the ignition and theinjection independently from one another inorder to shut down the engine.SensorsOutputsignalFunction processorcalculatescorrectiveactionsWatchdog processorchecksoutput signalsOutputsignalActuators210_013Engineis shut downif necessaryThe watchdog processor checks the function processor with thequery & answer function.The watchdog processor queries the functionprocessor with regard to, say, engine speed orignition advance angle. Then it checks whetherthe answer is correct. If a wrong answer is given,the error counter of the watchdog processor isincremented.The engine is shut down after five wronganswers.Five wrong answers can be detected in less thana half second.SensorsFunction processorqueriesanswersWatchdog processorActuators210_014Error counter12

The function processor checks the watchdog processorSensorsFunction processorqueriesgiveswrong answerWatchdog processorsendscountActuatorsTo monitor the watchdog processor, the functionprocessor deliberately gives a wrong answer.If the watchdog processor recognises the wronganswer, this error is registered in the error counterand returned to the function processor. If thewatchdog processor does not recognise thewrong answer, the error counter of the functionprocessor is incremented.The engine is shut down after the watchdogcounter fails to recognise five wrong answers.210_015The function processor gives no answer or gives an answer at the wrong point in timeFunction processornoanswerIn this case, the engine is shut down immediately.SensorsqueriesActuatorsWatchdog processor210_01613

System componentsThe accelerator pedal modulecomprises- the accelerator pedal,- accelerator pedal position sender -1- G79 and- accelerator pedal position sender -2- G185Two senders are used to ensure maximum safety.This system configuration is also known as a"redundant system".Redundant literally means "superfluous". In technicalterms, there is redundancy when, forinstance, an item of information occurs moreoften than is required for system operation.210_002AOpen housing on acceleratorpedal module showing sendersG79 and G185.Signal utilisationThe engine control unit is able to recognise thecurrent position of the accelerator pedal from thesignals supplied by the two accelerator positionsenders.Sliding contactpathSenderThe two senders are sliding contact potentiometersand are mounted on a common shaft.The resistances of the sliding contact potentiometersand the voltages transmitted to the enginecontrol unit vary with each change in theaccelerator pedal position.210_039The signal voltages are indicative ofkick-down and idling speed.The idling speed switch F60 in thethrottle valve control unit is no longerrequired.Accelerator pedal positionsender -1-Accelerator pedal positionsender -2-210_06414

Effects of signal failureThe following happens when one sender fails:- An entry is made in the fault memory and thefault indicator lamp for electrical throttlecontrol is activated.- The system initially activates the idling mode.If the second sender is found to be in theidling speed position within a defined testperiod, vehicle operation is resumed.- If full throttle is desired, the engine speed isincreased slowly.- The idling speed is also registered via thebrake light switch F orbrake pedal switch F47.- The convenience functions,e.g. cruise control system orengine braking moment control, aredeactivated.The following happens when both senders fail:An entry is made in the fault memory and thefault indicator lamp for Electronic Power Controlis activated.- The engine runs at a higher idling speed(max. 1500 rpm) only and no longer respondsto the accelerator.Simultaneous failure of both sendersmay not be identified properly dependingon the engine management system.- The fault indicator lamp is notactivated.- The engine runs at a higheridling speed and no longer respondsto the accelerator.Electrical circuitA voltage of 5 volts is present at both sliding contactpotentiometers.G79G185210_046For safety reasons, each sensor has its ownvoltage supply (red), its own earth connection(brown) and its own signal wire (green).R[Ω]G79G185A series-type resistor is fitted in sender G185.As a result, two different characteristics areobtained for the two senders. This is a prerequisitefor the safety and test functions.s[m]210_052The signal from the sender is read out in percent on the associated measured value block.Hence, 100% = 5 volts.15

System componentsThe throttle valve control unit J338is located on the intake manifold. It ensures that the engine is provided with the required air flow.DesignIt comprises- the throttle body,- the throttle valve,- throttle valve drive G186,- angle sender 1 forthrottle valve drive G187 and- angle sender 2 forthrottle valve drive G188.Throttle bodyThrottle valve driveHousing cover with integrated electronicsThrottle valveAngle senders 1+2 forthrottle valve driveGear wheel with spring returnsystem210_006Do not open or repair the throttle valve control unit.The basic setting procedure must be performed after replacing the throttle valve control unit.16

FunctionEnginecontrol unitAngle senders 1+2 forthrottle valve driveTo open or close the throttle valve, the enginecontrol unit activates the electric motor for throttlevalve drive.The two angle senders provide the engine controlunit with feedback on the current position of thethrottle valve.For safety reasons, two senders are used.DriveThrottle valve210_041Electrical circuitBoth angle senders have a commonvoltage supply (red) and earth wire (brown).Each of the two senders has its ownsignal wire (green).The throttle valve drive (blue) is activateddepending on the direction of movement.J338G187G188G186210_05117

System componentsThrottle valve drive G186The throttle valve drive is an electric motor and isactivated by the engine control unit.The throttle valve drive operates the throttle valveby means of a small gear.The throttle valve can be positioned in infinitelyvariable steps between the idling position andthe full-throttle position.210_028Throttle valve drive as shown at the housing cover of thethrottle valve control unit.Throttle valve position- The lower mechanical stopIn this position, the throttle valve is closed. It isrequired for the basic adjustment of thethrottle valve control unit.Throttle valvecontrol unit housingGearThrottle valve210_065Throttle valve driveReturn spring- The lower electrical stopis defined in the engine control unit and islocated just above the lower mechanical stop.During operation, the throttle valve is closedno further than the lower electrical stop. Thisprevents the throttle valve from intruding intothe housing.210_023Engine control unit18

- The emergency running positionWhen the throttle valve drive is deenergised,the throttle valve is set to the emergency runningposition by a spring return system. In this position,only limited vehicle operation is possible at ahigher idling speed.210_022Emergency running gap- The upper electrical stopis defined in the engine control unit. It is themaximum opening angle of the throttle valveduring vehicle operation.Shadow of throttle valveshaft210_025- The upper mechanical stopis positioned above the upper electrical stop.It does not affect engine power, however,because it is located in the "shadow" of thethrottle valve shaft.Throttle valveThrottle valve shaft210_026Effects of failureIf the throttle valve drive fails, the throttle valve isset to the emergency running positionautomatically.- An entry is made in the fault memory,and the fault indicator lamp for electricthrottle control is activated.- The convenience functions are deactivated(e.g. cruise control system).- Only emergency running functions areavailable to the driver.19

System componentsAngle sender 1 for throttle valve drive G187andangle sender 2 for throttle valve drive G188DesignThe two senders are sliding contactpotentiometers.The sliding contacts are located on the gearwhich is mounted on the throttle valve shaft.They scan the potentiometer strips in the housingcover.210_027Throttle valve shaftAngle senders 1 + 2FunctionThe resistances of the potentiometer strips - andtherefore also the signal voltages transmitted tothe engine control unit - vary with every changein the accelerator pedal position.The curves of both potentiometers areinverse. This allows the engine control unit todifferentiate between the two potentiometers andto execute test functions.Sliding contactG187CurveUThrottle valve anglePrinted circuit board withpotentiometer stripsUG188GearThrottle valve angle210_036Schematic diagram of sliding contact potentiometerThe angle of the throttle valve specified in percent in the measured value block.Hence, 0% corresponds to the lower electrical stop and 100% corresponds to the upperelectrical stop.20

Effects of signal failureThe engine control unit receives either an implausiblesignal, or no signal at all from an anglesender:- An entry is made in the fault memory, and thefault warning lamp for electrical throttle controlis activated.- Subsystems which influence torque(e.g. cruise control system or engine brakingmoment control) are deactivated.- The load signal is utilised to monitor theresidual angle sender.The engine control unit receives either an implausiblesignal, or no signal at all from the anglesenders:- An entry is made for both senders in the faultmemory, and the fault indicator lamp forelectric throttle control is activated.- The throttle valve drive is deactivated.- The engine runs at a higher idling speed of1500 rpm only and no longer responds to theaccelerator.- The accelerator pedal gives a normalresponse.21

System componentsThe fault indicator lampfor Electronic Power Control K132 is located inthe dash panel insert. It is a yellow lamp andbears the symbol "EPC“.EPC stands for Electronic Power Control.210_040When does the lamp come on?After turning on the ignition, the lamp comes on for 3 seconds. If there is no fault in the fault memory orif no fault is detected within this time period, the lamp goes off again.If there is a fault in the system, the engine control unit activates the fault indicator lamp, and an entry ismade in the fault memory.Electrical circuitThe fault indicator lamp is activated directly bythe engine control unit with an earth potential(brown).Effects of failureA defective fault indicator lamp has no effect onthe function of the throttle control, however, itleads to an entry in the fault memory.Visual indication of additional faults in the systemis no longer possible.J285K132210_04922

Auxiliary signalsBrake light switch F andbrake pedal switch F47210_042Signal utilisationBoth sensors are integrated in a componentlocated on the brake pedal.The "brake pressed“ signal is utilisedtwice for the purpose of Electronic Power Control.Brake pedal switch F47 serves as a backupinformation sender of the engine control unit.The "brake pressed“ signal- causes the cruise control system to beshut down- is utilised as a idling speed default if anaccelerator position sender fails.Effects of signal failureIf one of the two sensors fails or if the inputsignals are found to be implausible, the enginecontrol unit initiates the following actions:- Convenience functions such as the cruisecontrol system are deactivated.- If an accelerator position sender is defective,too, then the engine speed is limited to anincreased idling speed.Electrical circuitBrake light switch F is open in the normal positionand receives its voltage supply fromterminal 30.Brake pedal switch F47 is closed in the normalposition and receives its voltage supply fromterminal 15.+30 +15F F47210_04723

System componentsClutch pedal switch F36Signal utilisationThrough the signal from the clutch pedal switch,the engine control unit can recognise when theclutch pedal is pressed. The cruise control systemand the load change functions will then bedeactivated.210_043Electrical circuitThe switch is closed in the normal position andreceives its voltage supply from terminal 15.Effects of signal failureThe clutch pedal switch is not checked by the selfdiagnosisfunction. There is no substitute function.F36210_04824

Function diagramSSG79G185AABCDF F47 F36EJ ...J338G187 G188 G186K132J285FF36F47Brake light switchClutch pedal switchBrake pedal switchG79 Accelerator pedal position sender -1-G185 Accelerator pedal position sender -2-G186 Throttle valve driveG187 Angle sender -1-for throttle valve driveG188 Angle sender -2-for throttle valve driveK132SABCDEFault indicator lamp for Electronic PowerControlFusesCAN databusRoad speed signalCruise control systemAir conditioner compressor "ON/OFF“Diagnostic connection210_044J...J285J338Engine control unitControl unit with display unitin dash panel insertThrottle valve control unit25

Self-diagnosisThe following functions can be executed with theVehicle Diagnostic, Testing and InformationSystem VAS 5051 in connection with ElectronicPower Control:- 02 – Interrogate fault memory- 03 – Actuator diagnosis- 04 – Basic setting- 05 – Erase fault memory- 06 – End of output- 08 – Read data block210_102Function 04 – Basic settingThrottle valve control unitThe basic setting procedure must performedafter the engine control unit, the throttle valvecontrol unit or the complete engine has beenreplaced.At the same time, various positions of the throttlevalve are activated and stored in the engine controlunit.Please refer to the Workshop Manual!Accelerator pedal moduleFor several vehicles equipped with an automaticgearbox, it is necessary to perform the basic settingprocedure after replacing the acceleratorpedal module or the engine control unit, due theshort travel of the accelerator pedal. At the sametime, the kick-down position of the acceleratorposition sender is learned and stored in theengine control unit.Please refer to the Workshop Manual!26

Function 08 – Read data blockIn the "Read data block“ function, there are currently five display groups which refer to the ElectronicPower Control.- Display group 060 – Adaption of throttle valve control unitIn "Basic setting 04“, adaption of the throttle valve control unit is started byselecting "Display group 060“.060 Throttle valve angle(potentiometer 1 - G187)Throttle valve angle(potentiometer 2 - G188)Learn step counterAdaption condition[0...100%] [100...0%] [0...9] Text:ADP running / ADP OK /ADP ERROR- Display group 061 – Electronic Power ControlBox three in "Display group 061“ shows how far the throttle valve drive has opened thethrottle valve.061 Engine speed Supply voltageESB / EPCActivation of throttlevalve positioner[rpm] [V] [%] 0xxxOperating stateAir conditionercompressor ONDrive positionselectedA/C ready/rear windowheating ONalways 027

Self-diagnosis- Display group 062 – Electronic Power ControlIn "Display group 062“, the values of the two angle senders for throttle valve drive andthe two accelerator position senders are displayed.These values are given as a percentage and refer to a voltage of 5 volts.062 Throttle valve angle(potentiometer 1 - G187)Throttle valve angle(potentiometer 2 - G188)Accelerator pedalposition sender -1-(-G79)[0...100%] [100...0%] [0...98%] [0...49%]Accelerator pedalposition sender -2-(-G185)- Display group 063 – Kick-down adaptionIn "Basic setting 04“, adaption of the kick-down shift point is started by selecting "Display group 063“.063 Throttle valve angle(potentiometer 1 - G187)Throttle valve angle(potentiometer 2 - G188)Accelerator pedalpositionOperating states[0...100%] [100...0%] Kick-down Text:ERROR / press /ADP running / ADP OK28

- Display group 066 – Cruise control systemIn "Display group 066“, you can find information regarding the cruise control system.066 Road speed (actual) Switch position of brake,clutch and CCS[kph]xxxxBrake lightswitchBrake pedalswitchClutchswitchCruise controlsystem enabledSpecified road speed[kph]Switch position from CCScontrol panel switchxxxxCCS slide switch(latched)in OFF pos. yes/noCCS slide switch(latched/not latched) in OFFpositionyes/noSET button pressedyes/noCCSslide switch in RESposition yes/no29

Test your knowledge1. Name five torque demands which the engine control unit takes into account for the purposeof torque-oriented engine management.2. What "tools“ does the engine management system have to influence engine torque?3. Describe in note form the functions of the following components.3421210_0661. Accelerator pedal module:2. Engine control unit:3. Throttle valve drive:4. Angle sender for throttle valve drive:30

4. What points have to be observed when the throttle valve control unit is defective?a) After replacing the throttle valve control unit, vehicle operation can be resumed immediately.b) The throttle valve control unit can be repaired using a repair kit, and the accelerator positionsender must be replaced after all repair work on the throttle valve control unit.c) The throttle valve control unit must be replaced and the basic setting procedure must beperformed.31

Test your knowledgeSolutions:1.) Start, catalytic converter heating,Traction Control System, engine brakingcontrol, speed limiting device,power limitation, cruise control system,air conditioning system, automatic gearbox(shift point)2.) Throttle valve, charge pressure, injection time,cylinder suppression, ignition advance angle3.) Accelerator pedal module:- determines - with its senders - themomentary accelerator pedal position andtransmits a corresponding signal tothe engine control unit.4.) cEngine control unit:- receives the signals from the sensors,processes them and then controls theactuators.- checks the electrical throttle controlfunctionThrottle valve drive:- positions the throttle valveby means of an electric motorAngle senders for throttle valve drive:- signal the position of the throttle valve tothe engine control unit32

Notes33

34Notes

210For internal use only © VOLKSWAGEN AG, WolfsburgAll rights reserved. Technical specifications subject to change without notice.840.2810.29.20 Technical status: 05/99❀ This paper is produced fromnon-chlorine-bleached pulp.