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Tài liệu đào tạo về cảm biến và bộ chấp hành trên xe Ford Bộ tài liệu hay và chi tiết về hướng dẫn nguyên lý hoạt động của tất cả các cảm biến và bộ chập hành trên dòng sản phẩm xe Ford và Mazda AC Air Conditioning ABS Antilock Brake System BTCS Brake Traction Control System CJB Central Junction Box CTM Central Timer Module DTC Diagnostic Trouble Code EATC Electronic Automatic Temperature Control EBD Electronic Brake Force Distribution EGR Exhaust Gas Recirculation EPC Electronic Pressure Control EVAP Evaporative Emission FPDM Fuel Pump Driver Module GEM Generic Electronic Module IAC Idle Air Control IDS Integrated Diagnostic System IMRC Intake Manifold Runner Control LCD Liquid Crystal Display MAF Mass Air Flow MAP Manifold Absolute Pressure OSC Output State Control PCM Powertrain Control Module PTC Positive Temperature Coefficient PWM Pulse Width Modulation SRS Supplemental Restraint SS Shift Solenoid TCCS Timingcoast Clutch Solenoid TCC Torque Converter Clutch TCM Transmission Control Module WDS Worldwide Diagnostic System
Curriculum Training Sensors and Actuators Actuators Technical Service Training CG 8234/S en 12/2006 TC4012042H To the best of our knowledge, the illustrations, technical information, data and descriptions in this issue were correct at the time of going to print The right to change prices, specifications, equipment and maintenance instructions at any time without notice is reserved as part of FORD policy of continuous development and improvement for the benefit of our customers No part of this publication may be reproduced, stored in a data processing system or transmitted in any form, electronic, mechanical, photocopy, recording, translation or by any other means without prior permission of Ford-Werke GmbH No liability can be accepted for any inaccuracies in this publication, although every possible care has been taken to make it as complete and accurate as possible Copyright ©2007 Ford-Werke GmbH Service training programs D-F/GT1 (GB) Preface Present-day automotive engineering is becoming more and more complex During development activities, ever greater consideration has to be given to the environment and natural resources For this reason, closed and open-loop control systems are increasingly finding application in modern automotive engineering Actuators are used for the closed and open-loop control of a variety of electronic vehicle systems related, for example, to the engine, chassis, safety and comfort Actuators convert electrical energy into mechanical work (movement) and are used in electromechanical adjustment systems They can be used either purely as actuators, or as components in a closed or open-loop control circuit Currently, the most frequently used actuators in motor vehicles are electric motors and solenoids Based on the sensor signals they receive, the control modules calculate the variables for the control and consequently the activation of actuators In some cases, actuators are combined with sensors or integrated as complete systems which include a control module As a result the testing or replacement of individual actuators is often no longer possible Self-tests performed by control modules increasingly account for connected actuators and the related wiring Diagnosis is also performed using WDS ( Worldwide Diagnostic System)/IDS (Integrated Diagnostic System) The procedures and tests described in the Student Information relate to the electrical operation of the individual actuators Before performing the electrical tests, ensure that the malfunction is not the result of a mechanical fault The training course on sensors and actuators includes the following information for technicians: – Sensors, CG 8233/S (TC4012041H) – Actuators, CG 8234/S (TC4012042H) – Communications Network, CG 8235/S (TC4012053) Note: The supplied data and values only serve as demonstration and to facilitate understanding Current values should always be taken from current workshop literature Please remember that our training literature has been prepared for FORD TRAINING PURPOSES only Repairs and adjustments MUST always be carried out according to the instructions and specifications in the workshop literature Please make full use of the training offered by Ford Technical Training Courses to gain extensive knowledge of both theory and practice Service Training (G522585) Table of Contents PAGE Preface Lesson – General Information Open and closed-loop control Pulse width modulated signals Solenoids General Testing and measurement Electric motors General Motor versions Actuator motor 10 Testing and measurement 11 Piezoelectricity 12 The piezo-electric effect 12 Pyrotechnics 14 General 14 Design and operation 14 Testing and measurement 15 OSC mode 16 General 16 Test questions 17 Lesson – Actuators Exhaust gas recirculation (EGR) valves 18 Service Training Table of Contents Actuator motor-controlled EGR valve (DC motor) 18 Actuator motor-controlled EGR valve (stepper motor) 20 EGR valve (vacuum-controlled) 22 Intake manifold runner control (IMRC) electric motor 24 Swirl plate actuator 25 Throttle plate actuator motor 27 Fuel injector (petrol engines) 29 Fuel injector (diesel engines) 31 Electronic parking brake actuator 33 Electronic throttle plate 35 Electrical turbocharger guide vane adjustment actuator 37 Electrically heated thermostat 39 Window regulator motor 40 Roof opening panel motor 40 Parking brake actuator (TRW) 42 Blower motor 44 Glow plugs 46 Heater control valve 49 Air conditioning clutch 51 Instrument cluster 53 Fuel metering valve 55 Fuel pressure control valve 57 Engine cooling fan 59 Clutch actuator 61 Gearshift actuator 61 Idle air control (IAC) valve 63 Variable camshaft timing solenoid valves 65 Service Training Table of Contents Solenoid valves for vacuum control (engine management) 66 Solenoid valve for the shock absorber control system (active suspension) 68 Fuel pump driver module (FPDM) 69 Relay 70 Shift solenoid valve 71 Pressure control valve 71 Actuator motor-controlled intake manifold flap 73 Actuator motor-controlled intake manifold flap/charge air cooler bypass flap 74 Wiper motor 76 ABS/TCS actuator 78 Liftgate release actuator 80 Blend door actuator 81 Selector lever lock actuator 83 Ignition key removal inhibitor actuator 83 Door lock actuator 85 Pyrotechnic actuators 87 Air bag module 87 Safety Belt Pretensioners 88 Other actuators 90 Headlamp leveling motors 90 Mirror adjustment motors 90 Fuel filler door release actuator 90 Test questions 91 Answers to the test questions 92 List of Abbreviations 93 Service Training Lesson – General Information Open and closed-loop control Closed-loop control To understand the importance of sensors and actuators, we first need to examine the difference between open and closed-loop control This difference can be demonstrated using two examples provided below Open-loop control E59374 E59373 EGR (Exhaust Gas Recirculation) solenoid valve PCM (Powertrain Control Module) Vacuum line EGR valve Recirculated exhaust gas quantity A characteristic is saved in the PCM This characteristic indicates how far the EGR valve must open in order to achieve a particular recirculated exhaust gas quantity EGR solenoid valve PCM Vacuum line EGR valve Recirculated exhaust gas quantity Position sensor in EGR valve The setpoint value (50% in this example) determined for the EGR valve using the characteristic is compared with the actual value from the position sensor (measured variable, 45% in this example) in the EGRvalve For every setpoint value (desired EGR rate), there is a corresponding value for the control variable (position of the EGRvalve) E59375 Service Training (G522586) EGR solenoid valve PCM Vacuum line EGR valve Lesson – General Information Recirculated exhaust gas quantity Position sensor in EGR valve The difference between the setpoint value and actual value (50% as opposed to 45% in this example) is used to determine the actual position of theEGRvalve and perform a corresponding correction (55% in this example) to the control variable The frequency (formula symbol "f") is measured in Hertz (Hz) The pulse width is the duration of the active signal A Summary B The essential difference between open and closed-loop control lies in the comparison of setpoint values with corresponding measurement variables Whereas C closed-loop control involves this comparison, open-loop control does not E59656 Pulse width modulated signals PWM (Pulse Width Modulation) signals are square-wave signals with a constant frequency, but a variable activation time V Voltage (in volts) A 50% active (500 ms on and 500 ms off) B 25% active (250 ms on and 750 ms off) C 75% active (750 ms on and 250 ms off) The duty cycle is the ratio between the activation and deactivation times of a PWM signal The duty cycle is expressed as a percentage (%) Accordingly, a duty cycle of 25% means that the signal is active 25% of the time; over second of pulse width modulation, for example, the signal is active for 250 ms and inactive for 750 ms E59696 V Voltage (in volts) t Time The frequency is determined by the number of pulses (oscillations per second) Accordingly, the frequency increases / decreases proportionally to the number of pulses per second PWM signals can serve as output signals (e.g., boost pressure solenoid valve) as well as input signals (e.g., digital MAF (Mass Air Flow) sensor) The duty cycle can be measured with the help of an oscilloscope and the WDS/IDS datalogger (if supported) (G522586) Service Training Lesson – General Information General Solenoids Relay as an example of a solenoid In 1819, the Danish philosopher and physicist Christian Oersted (1777 – 1851) discovered that a compass needle is deflected by an electric current flowing through a conductor The discovery of the link between electricity and magnetism encouraged scientists and researchers to perform extensive experiments and investigations One of these scientists was André Marie Ampère (1775 – 1836) During these investigations, it became clear that the magnetism generated by electric current extends through space and produces a force which can be converted into motion and vice-versa If an electrical conductor (e.g copper) is wound to form a coil, the magnetic force depends on the number of windings and the strength of the energizing current If iron is located in this force field, it is attracted An iron core located within the coil bundles the field lines, amplifying the magnetic effect E60672 Yoke Armature Two-way contact Normally closed contact (break contact) Normally open contact (make contact) Relay coil Coil core Testing and measurement Electromagnetism is used in a variety of ways today, e.g in generators, transformers, relays, electric motors and last but not least in solenoids All solenoids operate by means of a coil and can only be tested to a limited extent using an ohmmeter Solenoids are used as actuators in motor vehicles, e.g as: During a continuity test only a coil open circuit or a short to ground can be detected A resistance test is only useful if the resistance value of the coil is known – coils in fuel injectors or luggage compartment release mechanisms – relays for operating circuit actuation – solenoid valves for ABS (Anti-lock Brake System) and automatic transmission – magnetic clutches for air conditioning compressors As a rule, the resistance value is low as only a relatively high current can generate a strong magnetic field A short circuit between the windings is therefore difficult to measure In many cases, correct operation can be checked using the OSC (Output State Control) mode in the WDS/IDS by activating the actuator If a test using the powerprobe is required in the test procedures, the actuator can be activated directly using external voltage via the powerprobe in order to check correct operation Service Training (G522586) Electric motors General Electric motor without housing Lesson – General Information Their power can range from a few milliwatts to several megawatts They can run at different speeds All electric motors operate according to the same principle – The armature, which is permanently attached to the axle, is brought into a rotational motion by the Lorentz force – The Lorenz force is the force acting upon conductors through which current is flowing in a magnetic force field E60666 Design and operation The South Tyrolean Johann Kravogl (1823 – 1889) is regarded as the inventor of the electric motor (in 1867) Electric motor components An electric motor is an electrical device which converts electrical energy into mechanical work with the aid of magnetic fields, by generating a force or a torque and consequently a movement Electric motors in everyday use Our contemporary technological world would be unimaginable without the use of electric motors Heavy locomotives are driven by electrical motors, as are kitchen appliances and miniature clockworks Electrical motors relieve human beings from physical work, e.g in industrial facilities and in the household Characteristics of electric motors Electric motors are: – economic, achieving efficiencies of up to 95 % (c.f petrol engines, max 45 %) – compact – relatively low-noise – easy to control and operate – inexpensive – virtually maintenance-free E60667 Housing (stator) Permanent magnets Rotor (armature) Housing cap with bearing and connections Electric motors basically consist of a rotor (moving part) and a stator (stationary part) Generally, the stator comprises a housing with magnets The brushes and electrical connections are located in the housing cap In brush motors (with armature coil), the stator usually comprises one or several permanent magnet(s) The rotor consists of the armature and an axle, which are bearing-mounted in the housing cap In electrical engineering, the term "armature" refers to a moving (G522586) Service Training Lesson – Actuators E54029 Potentiometer Two-part flexplate Drive motor This actuator is required for the return movement of the mechanical throttle plate The two actuator cables (accelerator pedal and throttle plate) and connected via a two-part flexplate During control intervention, the movement of the accelerator pedal cable is overridden by the electric motor so that the throttle plate is closed, contrary to driver input A potentiometer fitted to the traction control actuator informs the PCM about the current position of the traction control actuator Service Training (G522588) 79 Lesson – Actuators Liftgate release actuator Operating range Value Supply voltage Approx 12 V Signal type / voltage ON/OFF Resistance < Ohms (solenoid valve) Frequency – E60542 Testing options Example of a liftgate release actuator Connector DC motor Solenoid coil Diagnostic tool WDS/IDS DTC Compatibility Yes * Guided diagnostics (WDS/ – IDS) Installation position DMM + In the liftgate at the lock cylinder Datalogger ++ * OSC mode # ++ * Oscilloscope (breakout box and adapter cable required) – Powerprobe ++ Operating principle DC motor or solenoid coil Task / function ++ very suitable, + suitable The liftgate release actuator unlocks the liftgate or luggage compartment lid Depending on the system, unlocking may be performed by a DC motor or a solenoid coil - unsuitable, - - very unsuitable * In module-controlled systems (e.g GEM) via the module self-test A voltage is applied briefly to the DC motor or solenoid coil, actuating an unlocking lever via an integrated mechanism (DC motor) or directly (solenoid coil) Return is performed by a return spring in either case In contrast to vehicle doors, liftgates are not double-locked 80 (G522588) Service Training Lesson – Actuators Blend door actuator Operating range Value Supply voltage Approx 12 V Signal type / voltage E60462 Pulse signals (stepper motor) ON/OFF (all others) Resistance < 100 Ohm * Frequency – * Can only be measured in the case of motors with connections Examples of blend door actuators Actuator motor DC motor Stepper motor Testing options Diagnostic tool WDS/IDS DTC Installation position At the blower housing Compatibility Yes (stepper motors) No (all others) Guided diagnostics (WDS/ – IDS) DMM + (motors with two connections) – (all others) Datalogger ++ * Task / function OSC mode # ++ * Blend door actuators control the air flow in the air distribution housing Depending on the blend door being operated, actuators with different designations are used, e.g blend flap actuator, air distribution door actuator or temperature blend door actuator (see also "Special features") Oscilloscope (breakout box and adapter cable required) + (motors with two connections) – (all others) Powerprobe + (motors with two connections) – (all others) Operating principle Mechanical, pneumatic, DC motor, stepper motor Blend doors operated via stepper motors are adjustable virtually infinitely within their movement range ++ very suitable, + suitable - unsuitable, - - very unsuitable * Only with module-controlled air conditioning systems Service Training (G522588) 81 Lesson – Actuators Special features Possible designations / uses: – Air inlet blend door actuator As long as the vacuum is maintained in the actuator, the blend door remains in position Leaks in the actuator or in the vacuum system lead to failure of the pneumatic actuator – Defroster vent/air vent distribution door actuator – Footwell air vent flap actuator – Cold air bypass blend door actuator – Air distribution flap actuator – Temperature blend door actuator Pneumatic actuator E60461 Vacuum connection Diaphragm and return spring Blend door linkage Pneumatically actuated blend doors can only open or close In two-setting systems, an intermediate position is possible Pneumatic actuators are connected to the vacuum reservoir via hoses When a vacuum is applied to the actuator connection, the diaphragm and the linkage attached to it are fully retracted The blend door, which is attached to the extension of the linkage is opened If an actuator has two vacuum connections, it can move to three different positions When a vacuum is applied to only one connection, the linkage moves to an intermediate position When a vacuum is applied to both connections, the linkage is extended to the limit position 82 (G522588) Service Training Lesson – Actuators Selector lever lock actuator Operating range Value Ignition key removal inhibitor actuator A Supply voltage Approx 12 V Signal type / voltage ON/OFF Resistance < 16 Ohm Frequency – B Testing options Diagnostic tool E61127 A Ignition key removal inhibitor actuator B Selector lever lock actuator WDS/IDS DTC Compatibility No Guided diagnostics (WDS/ – – IDS) DMM + Installation position Datalogger – At the ignition lock or on the selector lever (vehicles with automatic transmission) OSC mode # – Oscilloscope (breakout box and adapter cable required) – Powerprobe ++ Operating principle Solenoid ++ very suitable, + suitable Task / function - unsuitable, - - very unsuitable The ignition key removal inhibitor actuator blocks the ignition lock, preventing the ignition key from being removed It is not activated, i.e not blocked, when de-energized The selector lever lock actuator prevents the selector lever from being moved from the P position It is activated, i.e not blocked, when de-energized Service Training (G522588) 83 Lesson – Actuators Special features TIE45383 Cover In the event of a fault, the selector lever lock can often be released manually A cover at the selector lever must be removed for this purpose A suitable object should then be inserted in the aperture, allowing the selector lever to be moved from the P position For further information, please refer to the relevant service literature or the Owner's Handbook 84 (G522588) Service Training Lesson – Actuators Door lock actuator During double locking, the mechanical connection of the release lever (interior of door) to the lock is interrupted The necessary DC motors are integrated in the various door locks and cannot be replaced separately At the driver-side front door, all the functions with the exception of double locking can be performed mechanically via the lock cylinder Operating range E60543 Example of a door lock actuator Release lever (exterior door handle) Cable to release lever (interior of door) Lever to release lever (exterior door handle) Connector Value Supply voltage Approx 12 V Signal type / voltage ON/OFF Resistance – Frequency – Installation position Testing options In the vehicle door Diagnostic tool Compatibility Operating principle WDS/IDS DTC DC motor(s) Guided diagnostics (WDS/ ++ IDS) Task / function DMM + Datalogger ++ OSC mode # ++ Oscilloscope (breakout box and adapter cable required) – Powerprobe ++ The door lock actuator has several functions, depending on the vehicle equipment: – Unlocking the door – Single locking the door – Double locking of the door During single locking, the mechanical connection of the release lever (exterior door handle) to the lock is interrupted Yes * ++ very suitable, + suitable - unsuitable, - - very unsuitable * In module-controlled systems (e.g GEM) via the module self-test Service Training (G522588) 85 Lesson – Actuators Special features In the central locking systems, various options with regard to the unlocking sequence are often available (e.g unlocking the driver door by pressing the remote control once) When testing a door lock actuator, currently activated option should be taken into account 86 (G522588) Service Training Lesson – Actuators Pyrotechnic actuators Air bag module Operating range Value Supply voltage – TIE41391 Example of a driver air bag Container Air bag inflator Air bag Padded cover cap Signal type / voltage DC/AC voltage, millivolts Resistance Approx – Ohms * Frequency – WARNING: * No resistance measurements must be performed in the vicinity of air bag igniters Testing options WARNING: The safety instructions contained in the relevant service literature must always be observed when working on air bags Installation position Diagnostic tool Depending on use: WDS/IDS DTC Compatibility Yes – in the steering wheel (driver air bag) – in the instrument panel (passenger air bag) Guided diagnostics (WDS/ – IDS) – in the front seat (side air bag) door-side – in the roof rail, between the A and C or D-pillar Operating principle Pyrotechnic Task / function Air bags protect vehicle occupants from injuries in the event of a crash/impact All air bag units consist of an igniter which inflates an air bag DMM –– Datalogger +* OSC mode # –– Oscilloscope (breakout box and adapter cable required) –– Powerprobe –– ++ very suitable, + suitable - unsuitable, - - very unsuitable * In some systems, the resistance of air bags can be displayed in In terms of the igniter, systems using an air bag inflator (driver air bag and passenger air bag in older systems) or with pre-filled gas cartridges (all except driver air bag) are used Service Training (G522588) the datalogger (air bag module) 87 Lesson – Actuators Safety Belt Pretensioners Operating range Value A B Supply voltage – Signal type / voltage E60541 DC voltage, millivolts Resistance – Ohm * Frequency – WARNING: * No resistance measurements must be performed in the vicinity of safety belt pretensioner igniters Examples of safety belt pretensioners A Safety belt pretensioner integrated in the safety belt retractor B Safety belt pretensioner on seat or seat track Installation position On seat or seat track or in safety belt retractor Operating principle Testing options WARNING: The safety instructions contained in the relevant service literature must always be observed when working on safety belt pretensioners Table does not apply to mechanical safety belt pretensioners Diagnostic tool Compatibility Mechanical (older systems), pyrotechnic with mechanical (Galaxy) or electrical (all others) triggering WDS/IDS DTC Task / function DMM –– Safety belt pretensioners ensure that the safety belts are held closely to the occupants' body in the event of an accident Datalogger +* OSC mode # –– Oscilloscope (breakout box and adapter cable required) –– Powerprobe –– The belt pretensioner can be triggered only once A triggered safety belt pretensioner does not affect the operation of the safety belt itself or retraction Pyrotechnic safety belt pretensioners, like air bags, operate using an igniter and a mechanical drive or a pretensioned spring (Galaxy only) Yes Guided diagnostics (WDS/ – IDS) ++ very suitable, + suitable - unsuitable, - - very unsuitable * In some systems, the resistance values for air bags can be displayed in the datalogger (air bag module) 88 (G522588) Service Training Lesson – Actuators A triggered safety belt pretensioner can be identified by means of the significantly shorter belt anchorage (exception: safety belt pretensioner integrated in safety belt retractor) In the case of a pyrotechnic belt pretensioner with electrical triggering, a DTC is always stored in the SRS module in the event of triggering Special features A safety belt pretensioner can only ever trigger once and must then always be replaced In the case of safety belt pretensioners integrated in the safety belt retractor, web grabbers/belt stoppers and belt tension limiters may also be installed In the case of replacement, the entire unit, including the safety belt must be replaced Mechanical safety belt tensioners trigger a pretensioned spring via a spring-mass sensor Service Training (G522588) 89 Other actuators Headlamp leveling motors Lesson – Actuators Operating range Value Mirror adjustment motors Supply voltage Approx 12 V Signal type / voltage ON/OFF * Pulse signals (adaptive forward lighting) PWM signals (headlamp leveling) ** Fuel filler door release actuator Installation position In the headlamps In the exterior mirrors Resistance – At the fuel filler door Frequency – * Mirror adjustment, fuel filler door Operating principle DC motor (headlamp leveling system, mirror adjustment, fuel filler door), stepper motor (adaptive front lighting) ** Cannot be measured, integrated in the motor Testing options Diagnostic tool Compatibility Task / function WDS/IDS DTC Motors for mirror adjustment alter the position of the mirror glass in the horizontal and vertical directions as well as the mirror housing (folding function) Guided diagnostics (WDS/ – IDS) Yes * No (all others) Headlamp leveling motors adjust the headlamp reflector in the horizontal direction DMM + Datalogger + In the case of adaptive forward lighting, the headlamp reflector is adjusted in the vertical direction OSC mode # ++ * Oscilloscope (breakout box and adapter cable required) – Powerprobe – The fuel filler door actuator locks and unlocks the fuel filler door ++ very suitable, + suitable - unsuitable, - - very unsuitable * With high intensity discharge lamps and adaptive front lighting Focus 2004.75 and Focus C-MAX 2003.75 90 (G522588) Service Training Lesson – Actuators Test questions Tick the correct answer or fill in the gaps Airbag resistors must not be tested using a multimeter a True b False When testing blower motors and cooling fans, it should be noted that: a these are always designed as brushless motors b a DTC is always stored in the event of a defective blower motor c depending on the version, a serial resistor is defective although the blower motor is operative d these are only used in conjunction with air conditioning systems During testing using the powerprobe a nothing needs to be noted b it should be noted that no positive voltage is applied to the module c only ground should be connected in all cases d it should be noted that only electric motors can be tested To check stepper motors a the powerprobe should always be used b it is sufficient to perform a continuity test to the coils c the OSC mode is always available d the OSC mode should be used where possible Fuel injectors can always be checked using the powerprobe as they are always solenoid valves a True b False Service Training (G522589) 91 Answers to the test questions Lesson – General Information c c rotor stator; b b b Lesson – Actuators a c b d b 92 Service Training List of Abbreviations A/C Air Conditioning SS Shift Solenoid ABS Anti-lock Brake System T/CCS Timing/coast Clutch Solenoid BTCS Brake Traction Control System TCC Torque Converter Clutch CJB Central Junction Box TCM Transmission Control Module CTM Central Timer Module WDS Worldwide Diagnostic System DTC Diagnostic Trouble Code EATC Electronic Automatic Temperature Control EBD Electronic Brake Force Distribution EGR Exhaust Gas Recirculation EPC Electronic Pressure Control EVAP Evaporative Emission FPDM Fuel Pump Driver Module GEM Generic Electronic Module IAC Idle Air Control IDS Integrated Diagnostic System IMRC Intake Manifold Runner Control LCD Liquid Crystal Display MAF Mass Air Flow MAP Manifold Absolute Pressure OSC Output State Control PCM Powertrain Control Module PTC Positive Temperature Coefficient PWM Pulse Width Modulation SRS Supplemental Restraint System Service Training 93 ... specifications, equipment and maintenance instructions at any time without notice is reserved as part of FORD policy of continuous development and improvement for the benefit of our customers No part of... mechanical, photocopy, recording, translation or by any other means without prior permission of Ford- Werke GmbH No liability can be accepted for any inaccuracies in this publication, although... every possible care has been taken to make it as complete and accurate as possible Copyright ©2007 Ford- Werke GmbH Service training programs D-F/GT1 (GB) Preface Present-day automotive engineering