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`u.s. Department
`of Transportation
`National Highway
`Traffic Safety
`Administration
`
`DOT-HS-807-367
`DOT -TSC-N HTSA-89-1
`Final Report
`
`January, 1989
`
`An Examination of Sudden Acceleration
`
`John Pollard
`E. Donald Sussman
`
`U.S. Department of Transportation
`Research and Special Programs
`Administration
`Transportation Systems Center
`Cambridge, MA 02142
`
`Prepared for
`
`National Highway Traffic Safety Administration
`Office of Defects Investigation
`400 7th Street. SW
`Washington. DC 20590
`
`This docum ent IS available to t he public fr om the National Technical Information Service , Springfield ,Virginla 22161 .
`
`Ford Motor Company et al.
`Ex. 1007-001
`
`

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`1. Report No.
`DOT-HS-807-367
`
`4. Title ond Subtitle
`
`An Examination of Sudden Acceleration
`
`2. Government Accession No.
`
`3. Recipient's Catalog No.
`
`Technical Report Documentation Page
`
`S. Report Date
`January 1989
`6. Performing Orgoni zation Code
`DTS-45
`
`~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~8. Performing Orgonization Report No.
`7. Authorf sl
`DOT-TSC-NHTSA-89-l
`John Pollard and E. Donald Sussman
`
`9. Performing Organization Name and Address
`U.S. Department of Transportation
`Research and Special Projects Administration
`Transportation Systems Center
`Cambridge, MA 02142
`
`10. Work Unit No. (TRAISl
`HS9l0/S9024
`11. Contract or Grant No.
`N.A.
`
`13. Type of Report and Period Covered
`~~~-----------------------~~--------------------------------------------~
`Final Report
`12. Sponsoring Agency Name and Address
`U.S. Department of Transportation
`1987 - 1988
`National Highway Traffic Safety Administration
`400 7th Street, S.W.
`Washington, DC
`20590
`
`14. Sponsoring Agency Code
`NEF-IO
`
`IS. Supplementary Notes
`
`I
`
`16. Abstroct
`This report describes the results of a study to identify and evaluate factors ~.;hich
`could potentially cause or contribute to the occurrence of "Sudden Acceleration
`Incidents" (SAl). SAl are defined in this report as unintended, unexpected, high(cid:173)
`power accelerations from a stationary position or a very low initial speed accompanied.
`by an apparent loss of braking effectiveness. Ten vehicles with above-average SAl
`complaint rates were selected for particular scrutiny.
`(1) convened!
`In the course of conducting this study, the Transportation Systems Center:
`a panel of independent experts in various disciplines related to SAl concerns to review
`this material with TSC; (2) collected the rel~vant literature and case documentation on
`the vehicles; (3) studied the fuel-systems, braking systems, and driving controls of
`the vehicles; (4) performed appropriate tests and experiments or arranged for their
`conduct at NHTSA's Vehicle Research and Test Center (VRTC); and (5) documented the
`findings and conclusions, as noted below.
`(1) No malfunctions were found which could cause high engine power without opening the
`throttle.
`(2) Certain malfunctions were identified which could cause throttle opening
`or sticking, but these would be readily detectable in post-SAl investigation.
`(3) Other
`malfunctions were found that could cause modest increases in engine power, some of which.
`would be difficult to detect in an investigation. These malfunctions could not directly'
`cause an SAl but might startle the driver into a pedal misapplication (depression of the
`accelerator instead of, or in addition to, the brake pedal).
`(4) Vehicle pedal design
`features were identified which might increase the probability of a pedal misapplication.
`All the vehicles with high SAl-compliant rates which were measured were found to
`possess pedal designs conducive to pedal misapplication.
`17. Key Wo,ds
`18. Distribution Stat_ent
`Sudden Acceleration, Vehicles, Pedal
`Design, Engine Controls, Cruise Control,
`Brakes, Human Factors
`
`DOCUMENT IS AVAILABLE TO THE PUBLIC
`THROUGH THE NATIONAL TECHNICAL
`INFORMATION SERVICE, SPRINGFIELO,
`VIRGINIA 2216~
`
`19. Security Classif. (of this ,eport)
`
`20. Security Classif. (of this page)
`
`21. No. of Pages
`
`22. Price
`
`Form DOT F 1700.7 (8-72)
`
`Reproduction of completed page aut~orized
`
`Ford Motor Company et al.
`Ex. 1007-002
`
`

`

`Notice
`
`This document is disseminated under the sponsorship of the Department of Transportation
`in the interest of informatiQn exchange.
`
`Notice
`
`The United States Government does not endorse products or manufacturers. Trade or
`manufacturers' names appear herein solely because they are essential to the object of this
`report.
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`Ford Motor Company et al.
`Ex. 1007-003
`
`

`

`Preface
`
`This report was prepared by the U.S. Department of Transportation, Transportation
`Systems Center (TSC) for the National Highway Traffic Safety Administration, Office of
`Defects Investigation. The work was performed by TSC's Operator Performance and Safety
`Analysis Division.
`
`The authors are also indebted to the numerous vehicle owners who consented to be
`interviewed about their experiences with sudden acceleration, some of whom also provided
`vehicles for testing. The cooperation of vehicle manufacturers and dealers who supplied
`extensive technical documentation, parts and test vehicles is gratefully acknowledged.
`Finally, the assistance of public-interest safety groups in directing drivers involved in
`sudden-acceleration incidents to contact TSC as soon as possible after an accident was most
`helpful.
`
`jj
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`Ford Motor Company et al.
`Ex. 1007-004
`
`

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`TABLE OF CONTENTS
`
`EXECUTIVE SUMMARY
`
`1.0 INTRODUCTION
`
`1.1
`
`1.2
`
`1.3
`
`BACKGROUND
`
`OBJECTIVES
`
`PANEL MEMBERSHIP
`
`2.0 DATA SOURCES
`
`3.0 TECHNICAL DISCUSSION AND CONCLUSIONS
`
`3.1
`
`VEHICLE SYSTEMS RELEVANT TO SAl
`
`3.1.1
`
`3.1.2
`
`3.1.3
`
`3.1.4
`
`3.1.5
`
`PROBABLE CAUSES AND FAILURE MODES
`
`CRUISE-CONTROL MALFUNCTIONS
`
`TRANSMISSION MALFUNCTIONS
`
`IDLE-SPEED CONTROL MALFUNCTIONS
`
`BRAKE SYSTEM MALFUNCTIONS
`
`3.2
`
`ELECTROMAGNETIC AND RADIO-FREQUENCY INTERFERENCE
`
`3.2.1
`
`3.2.2
`
`3.2.3
`
`ELECTROMAGNETIC INTERFERENCE
`
`RADIO-FREQUENCY INTERFERENCE
`
`ELECTROSTATIC DISCHARGE TESTING
`
`3.3
`
`ERGONOMIC AND BEHAVIORAL FACTORS
`
`3.3.1
`
`3.3.2
`
`3.3.3
`
`VEHICLE/DRIVER INTERACTIONS
`
`AUTOMATIC-SHIFT-LOCK EFFECTS
`
`REPORTING FACTORS
`
`3.4
`
`TECHNICAL SUMMARY
`
`iii
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`v
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`1
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`1
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`1
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`2
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`3
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`5
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`8
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`8
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`8
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`15
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`15
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`16
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`22
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`22
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`23
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`29
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`32
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`32
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`43
`
`46
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`49
`
`Ford Motor Company et al.
`Ex. 1007-005
`
`

`

`APPENDIX A: Curricula Vitae of Panel Members
`
`APPENDIX B: Office of Defects Investigation Information Request
`Dated January 29, 1988
`
`APPENDIX C: Office of Defects Investigation Information Request
`Dated February 25, 1988
`
`APPENDIX D: Technical References
`
`APPENDIX E: Cruise Control, Braking and Electrostatic Discharge
`Tests Conducted By The Vehicle Research and Test Center
`
`APPENDIX F: Bench Test Procedures For Cruise Controls and
`Sample Output
`
`APPENDIX G: "Critical Vertical Offset" Measurement Procedure
`and Data
`
`APPENDIX H: Study of Mechanical and Driver-Related Systems of
`The Audi 5000 Capable of Producing Uncontrolled Sudden
`Acceleration Incidents
`
`A-1
`
`B-1
`
`C-1
`
`D-1
`
`E-1
`
`F-1
`
`G-1
`
`H-1
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`Ford Motor Company et al.
`Ex. 1007-006
`
`

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`E;xecutive Summary
`
`Background This report describes the results of a study to identify and evaluate
`factors which could potentially cause or contribute to the occurrence of
`"Sudden Acceleration Incidents" (SAl). For the purposes of this report
`SAl are defined as unintended, unexpected, high-power accelerations
`from a stationary position or a very low initial speed accompanied by an
`apparent loss of braking effectiveness. The typical SAl scenario, as
`abstracted from National Highway Traffic Safety Administration's
`(NHTSA) complaint files, begins at the moment of shifting to "Drive" or
`"Reverse" from "Park." Most of the reported SAl terminate in some
`form of collision with another vehicle or a fixed object and include
`driver statements concerning lack of braking effectiveness. Incidents
`which are made known to NHTSA are "Reported Sudden Acceleration
`Incidents," hereinafter abbreviated as RSAl. NHTSA's files include
`thousands of these reports, including almost every make of vehicle,
`virtually all of which occurred in vehicles with automatic transmissions.
`
`The factors which cause andlor contribute to the occurrence of SAl have
`been a matter of considerable public controversy and media attention.
`To help resolve this controversy and to explore topics not fully
`investigated previously, the Administrator of NHTSA ordered an.
`independent review of the current state of understanding of the SAl
`phenomenon in October, 1987. Because of the knowledge and
`experience it gained while assisting NHTSA with the Audi 5000
`investigation, the Transportation Systems Center (TSC) was chosen to
`conduct this review. Ten make/modeVyear vehicles with above-average
`SA complaint rates were selected for particular scrutiny:
`
`Make
`
`Audl
`
`Audl
`
`Buick
`
`Cadillac
`
`Chevrolet
`
`Chrysler
`
`Mercedes
`
`Mercury
`
`Nissan
`
`Toyota
`
`Model
`
`5000
`
`5000
`
`LeSabre
`
`Coupe deVille
`
`Camara
`
`New Yorker
`
`300E
`
`Grand Marquis
`
`300ZX
`
`Cressida
`
`V
`
`Year
`
`1985
`
`1983
`
`1986
`
`1985
`
`1984
`
`1984
`
`1986
`
`1984
`
`1985
`
`1984
`
`Ford Motor Company et al.
`Ex. 1007-007
`
`

`

`Although specific make/modeVyear vehicles are cited above, these
`vehicles are representative of a much larger group. Not all of the above
`listed vehicles have unusually high RSAI rates; some were chosen so
`that the study included certain design approaches which are used
`throughout a
`large number of models produced by
`the same
`manufacturer. Accident investigations and other vehicle tests included
`. a broad range of vehicles.
`
`Procedure To accomplish this, TSC:
`
`• convened a panel of independent experts in various disciplines
`related to SAl concerns to review this material with TSC,
`
`• collected the relevant literature and case documentation on
`the vehicles,
`
`•
`
`interviewed SAl-involved drivers,
`
`• studied the fuel-systems, braking systems, and
`controls of the vehicles,
`
`driving
`
`• performed appropriate tests and experiments or arranged for
`their conduct at NHTSA's Vehicle Research and Test Center
`(VRTC), and
`
`• documented the findings and conclusions.
`
`TSC and the Panel were specifically charged with the responsibility to
`consider all of the potentially viable hypotheses as to the causal and
`contributing factors of SAl and to specify tests of each hypothesis
`through both engineering analyses and experimentation, wherever
`feasible.
`
`In the study the following logical assumptions were used:
`• SAl could be the result of a single primary causal factor or
`could result from the action of a number of factors which
`contribute to or increase the likelihood of an SAl.
`
`• Factors related to SAl occurrence can include power-train
`design, brake system design, and vehicle ergonomics
`(particularly pedal configuration).
`
`• An SAl must involve a significant increase in engine power,
`which could be caused by a failure in an engine-control system
`or a pedal misapplication (inadvertent depression of the
`accelerator instead of, or in addition to, the brake).
`
`vi
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`Ford Motor Company et al.
`Ex. 1007-008
`
`

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`• If the SAl begins with a vehicle-system malfunction, loss of
`control could occur through braking system failure or the
`driver's failure to press the brake with sufficient force and/or
`the driver inadvertently pressing the accelerator.
`
`• If the SAl is initiated by a pedal misapplication of which the
`driver is unaware, loss of control can occur.
`
`• The location, orientation, and force-deflection characteristics
`of pedals can influence the probability that the driver will
`mistake one pedal for another.
`
`• If the cause of an SAl is an electro-mechanical or mechanical
`failure, it should produce evidence of failure.
`
`• If the cause of an SAl is an intermittent electronic failure,
`physical evidence may be very difficult to find, but the failure
`mode should be reproducible either through in-vehicle or
`laboratory bench tests.
`
`• The vehicles studied mayor may not share the same causal
`and contributing factors.
`
`The study covered:
`
`• engines and their controls, as well as transmissions, to
`determine whether and how they might produce unwanted
`power;
`
`•
`
`the role of electromagnetic and radio-frequency interference
`(EMIJRFI) and other environmental variables in stimulating
`malfunctions in critical engine controls;
`
`• braking systems, which were examined with a view as to how
`. they could fail momentarily but spontaneously recover normal
`function; and
`
`•
`
`the role of human factors or ergonomic control design
`considerations which might lead to pedal misapplications.
`
`vii
`
`Ford Motor Company et al.
`Ex. 1007-009
`
`

`

`Findings
`
`Powertrain
`
`In the course of its investigations, TSC encountered a substantial
`number of incidents in which malfunctions of the vehicle caused
`unwanted and substantial power output. The vast majority of these were
`mechanical in nature. These were mainly broken or ill-fitting parts in
`the throttle assembly or accelerator linkage which caused the throttle to
`remain open even when the driver's foot was off the accelerator. In
`most cases of mechanical failure, they were easy for an investigator to
`recogruze.
`
`Electronic faults leading to increased engine power were found to occur
`in the idle stabilizer systems of some Audi 5000s. When certain failure
`modes occurred in these models, the power-output increase produced
`an acceleration of less than 0.3 g for less than 2 seconds. While this
`acceleration is significant, it is far less than the full-power conditions
`characteristic of SAl. Two experimental studies of driver behavior were
`cited which demonstrated that such deliberately induced accelerations
`could startle some drivers into making pedal misapplications. In the
`other make-models evaluated, the maximum acceleration resulting from
`an idle stabilizer fault is less than 0.3 g (producing only excessive creep),
`and thus is less likely to startle the driver. It was concluded that such a
`fault could not provide the high power characteristic of an SAl, but
`could have startled the driver and thereby contributed to a pedal
`misapplication leading to high-power acceleration.
`
`A few verified instances of cruise-control failure leading to wide open
`throttle were reported, but they occurred when the vehicle was already
`travelling at considerable speed and their causes were readily detected
`in post-incident investigations. In all of these instances, application of
`the brake caused the cruise control to disengage and usually allowed the
`vehicle to stop without crashing.
`
`Extensive laboratory testing of the operation of cruise controls under
`stress from temperature extremes, power supply variations, EMI/RFI
`and high-voltage discharges has demonstrated no failure modes of any
`relevance to SAl. Analysis of their circuitry shows that for nearly all
`controls designed in the past few years, two or more independent,
`intermittent failures would have to occur simultaneously to cause
`throttle opening in a way that would be difficult to detect after the
`incident. The occurrence of such simultaneous, undetectable failures is
`virtually impossible. Among the cruise control systems examined in this
`study, only one has been shown to be capable of causing throttle
`opening as a result of a single-point failure, namely that used on the
`1983 Audi. These could conceivably have played a role in a small
`number of incidents, but most vehicles which experienced SAl were not
`equipped with such units and no such failure has ever been documented.
`
`viii
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`Ford Motor Company et al.
`Ex. 1007-010
`
`

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`Braking
`system
`
`'Failures in other, electronic controls, notably fuel-system control
`computers, were ju~ged to be incapable of causing the engine power
`required to cause an SAlbecatise they do not actuate the throttle on any
`car. Substantial throttle opening is required to provide the airflow into
`the engine necessary for high power output.
`
`Vacuum-hose and other leaks which increase the flow of air into the
`intake manifold can produce only small increases in power because the
`resulting incremental fuel flow is quite limited. Furthermore, such leaks
`should be easily detectable in a post-SAl investigation, but such
`evidence has not been reported.
`
`In the typical SAl, the driver stated that the vehicle did not stop even
`though the brakes were fully applied, and reported brake failure. Yet
`the physical evidence which must accompany brake failure was evident
`in only a handful of the thousands of SAl involved vehicles reported to
`NHTSA. No plausible mechanisms could be identified for temporary,
`self-correcting brake failure which are relevant to SAl. Hence, actual
`brake system failure plays no significant role in SAl.
`
`Less-than-expected brake effectiveness could be interpreted by the
`driver as brake failure. Every vehicle. tested showed some increase in
`minimum stopping distance when its throttle was held wide open during
`braking. Factors such as engine power, drive-wheel configuration
`(front/rear wheel), front/rear weight bias, and direction of travel affect
`both the minimum stopping distance and the required brake-pedal
`effort. For
`three of
`the
`tested vehicles,
`in
`the extreme
`wide-open-throttle test condition, the force necessary to stop the
`vehicles in the minimum distance was beyond the capability of weaker
`drivers. This condition would be relevant in situations in which the
`throttle became stuck open after the driver pressed the accelerator
`pedal. It could also be relevant in cruise-control failures resulting in
`throttle opening at speed; (however, such failures, in which the cruise
`control could be neither overriden nor disengaged by pressing the brake
`pedal, are seen as almost impossible). This condition could also be
`relevant in situations in which the driver has pressed both the brake and
`accelerator pedals simultaneously. Weaker drivers may not press hard
`enough on the brake pedal to overcome the effect of also pushing on the
`accelerator pedal. However, for most SAl, the most plausible cause of
`an open-throttle condition while attempting to brake
`is pedal
`misapplication, which is likely to be perceived as brake failure.
`
`ix
`
`Ford Motor Company et al.
`Ex. 1007-011
`
`

`

`Human
`factors
`
`Pedal
`Human factors play a large role in the SAl problem.
`misapplications are the most probable explanation for the vast majority
`of sudden acceleration incidents in which no vehicle malfunction is
`evident. Even in cases where vehicle malfunctions exist which startle or
`otherwise distract the driver, it is often pedal misapplication which is the
`It is hypothesized that the high
`direct cause of high engine power.
`SAl-complaint rates for certain make-model vehicles are likely to be
`related to the following vehicle control characteristics:
`
`•
`
`relatively close lateral pedal placements (increasing the
`likelihood of pedal misapplication);
`
`• pedal force displacement attributes that result in similarity of
`feel (thus reducing the chances that an error will be
`recognized);
`
`• pedal travel, vertical offset, and other characteristics which
`permit engine torque to exceed brake torque when the
`driver's foot overlaps both pedals; and
`
`the
`to make
`• sufficient vehicle acceleration capability
`consequences of the error occur before the driver has time to
`take corrective action.
`
`Although all of the vehicles with the highest RSAI rates possess the
`characteristics, there are some vehicles with these characteristics which
`do not have particularly high SAl complaint rates. Other variables, such
`as the angular placement of pedals, engine noise levels, etc. may also
`influence the probabilities of occurrence and of prompt recognition of a
`pedal misapplication.
`
`Recommen(cid:173)
`dations
`
`Three potential approaches to reduce pedal misapplica.tions related to
`SAl through design changes were identified:
`
`• moving the pedals further apart laterally, thus reducing the
`possibility of stepping on both pedals with the same foot or
`stepping on the wrong pedal;
`
`•
`
`•
`
`raising the brake pedal with respect to the accelerator, making
`the pedals more distinguishable
`and
`reducing
`the
`consequences of stepping on both pedals; and
`
`installing automatic shift-locks (which require that the driver
`apply the brakes before putting the car in motion), thus
`eliminating the possibility of engaging the transmission while
`
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`Ford Motor Company et al.
`Ex. 1007-012
`
`

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`the accelerator is depressed, and also effectively training
`drivers to ·use correct foot placement consistently so that
`under conditions where the driver is startled or disoriented
`misapplications will be less likely.
`
`These design approaches could not completely eliminate SAl, but each
`could contribute, alone or in combination, to a reduction in the
`frequency of its occurrence. While the majority of automobiles in use in
`the United States already have pedal configurations consistent with the
`first two approaches, it must be recognized that such configurations may
`have other effects on driver braking performance. For example, they
`may slightly increase the time required to begin braking. Such effects
`must be quantified and evaluated before making any recommendations
`for pedal-design changes. A major study of this topic. is currently in
`progress under the sponsorship of NHTSA's Office of Research and
`Development.
`
`The automatic shift-lock has been adopted or is being considered by a
`number of manufacturers. Reported complaint rates for cars retrofitted
`with shift-locks have been lower than for comparable cars without them.
`This approach has no adverse consequences for safety and should also
`provide some ancillary benefits, such as preventing unattended small
`children from shifting a car out of "Park."
`
`xi
`
`Ford Motor Company et al.
`Ex. 1007-013
`
`

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`An Examination of Sudden Acceleration
`
`1.0 INTRODUCTION
`
`1.1 BACKGROUND
`
`In recent years as the term "sudden acceleration" has been popularized by the media, there
`has been a trend toward using it in complaints about any incident involving an unexpected
`change in vehicle speed, including throttle sticking, excess idle speed, engine surging,
`unintended acceleration occurring when the vehicle was already travelling at considerable
`speed, etc. This overuse of the term has inflated SAl statistics. To differentiate them from
`other types of problems with unwanted engine power, "sudden acceleration incidents" (SAl)
`are defined for the purposes of this report as unintended, unexpected, high-power
`accelerations from a stationary position or a very low initial speed accompanied by an
`apparent loss of braking effectiveness. In the typical scenario, the incident begins at the
`moment of shifting to "Drive" or "Reverse" from "Park." Most of the reported incidents
`terminate in some form of collision with another vehicle or fixed object and include driver
`statements concerning lack of braking effectiveness. Incidents which are made known to
`NHTSA are "Reported Sudden Acceleration Incidents," hereinafter abbreviated as RSAl.
`
`.
`.
`1.2 OBJECTIVES
`
`Over the past 15 years, the NHTSA has conducted more than 100 separate investigations of
`SAl complaints involving more than 20 manufacturers. Forty-four of them have been
`Initially they were treated as unrelated
`opened since 1980, resulting in eleven recalls.
`matters with each considered on its own merits and without any attempt at an overview
`across the many different makes and models affected.
`
`In order to secure an independent review of the current state of understanding of the
`sudden acceleration phenomenon and to explore topics not fully investigated previously,
`NHTSA requested that the Transportation Systems Center collect the relevant literature
`and case documentation, examine the braking and fuel-system controls of ten vehicles with
`above-average RSAI rates, conduct experiments as required, and engage a Panel of outside
`experts in various disciplines to review this material and report its findings and conclusions.
`
`This document reports the conclusions of this study based upon information obtained from
`incident-involved drivers, review of the literature, examination of .the components and
`technical documents provided by the manufacturers, extensive measurement of the behavior
`of the vehicles under simulated fault conditions at the Vehicle Research and Testing
`Center, laboratory simulations of the effects of interference sources on cruise controls,
`expert knowledge and panel discussions held at TSC.
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`Ford Motor Company et al.
`Ex. 1007-014
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`

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`1.3 PANEL MEMBERSHIP
`
`The panel membership was as follows:
`
`Name
`
`Affiliation
`
`Area of Expertise
`
`John Adams
`
`David Fischer
`
`John Heywood
`
`Louis Klusmeyer
`
`National Institute
`of Standards
`and Technology
`
`Arthur D. Little, Inc.
`
`Massachusetts Institute
`of Technology
`
`Southwest Research
`Institute
`
`Electromagnetic and Radio-
`Frequency Interference
`
`Analog Circuitry
`
`Engine Controls
`
`Brake Systems
`
`Raymond Magllozzi
`
`Good N~ws Garage
`
`Mechanical Diagnosis
`
`Philip Sampson
`
`Gary Stecklein
`
`Benjamin Treichel
`
`Tufts University
`
`Southwest Research
`Institute
`
`Southwest Research
`Institute
`
`Human Factors
`
`Transmissions
`
`Digital Circuitry
`
`Each panel member's curriculum vitae is contained in Appendix A.
`
`2
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`Ford Motor Company et al.
`Ex. 1007-015
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`An Examination of Sudden Acceleration
`
`2.0 DATA SOURCES
`
`In the course of the many investigations of sudden acceleration by NHTSA in recent years,
`the collection of incident reports and technical documentation has become quite
`voluminous. In order to focus this study, detailed technical analysis was concentrated on the
`following vehicles for which significant numbers of sudden-acceleration complaints have
`been received:
`
`Table 2-1: Listing of vehicles subjected to detailed analysis.
`
`Make
`
`Audi
`
`Audi
`
`Buick
`
`Cadillac
`
`Chevrolet
`
`Chrysler
`
`Mercedes
`
`Mercury
`
`Nlssan
`
`Toyota
`
`Model
`
`5000
`
`5000
`
`LeSabre
`
`Coupe deVille
`
`Camaro
`
`New Yorker
`
`300E
`
`Grand Marquis
`
`300ZX
`
`Cress ida
`
`Year
`
`1985
`
`1983
`
`1986
`
`1985
`
`1984
`
`1984
`
`1986
`
`1984
`
`1985
`
`1984
`
`For each of these vehicles the following types of data were acquired:
`
`1. Complete shop manuals with supplementary electrical wiring diagrams
`where available, purchased through commercial sources (Appendix D).
`
`2. Relevant studies performed by NHTSA, its contractors and TSC
`(Appendix D).
`
`3. Copies of test reports, studies, or analyses of the sudden acceleration
`problem performed by each manufacturer or its suppliers, contractors,
`etc., acquired by the Office of Defects Investigation from all of the firms
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`3
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`Ford Motor Company et al.
`Ex. 1007-016
`
`

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`listed above as well as BMW, Honda, Mazda, SAAB, Subaru, and Volvo.
`The letter requesting this information is reproduced in Appendix B.
`
`4. Extensive technical documentation, including proprietary material, was
`received for the electrical, braking and engine-control· systems. These
`responses included complete schematic and parts-layout diagrams for the
`engine-control computers and cruise-control system as well as the
`source-code listing for control programs. Appendix C contains a copy of
`the letters detailing these requirements.
`
`5. Samples of the engine-control computer and (if separate) cruise-control
`computer and idle-stabilizer controller were also received.
`
`In addition to the vehicle-specific material listed above, scores of articles from magazines
`and newspapers dealing with SAl were acquired and reviewed. Such articles tend to repeat
`one another, but several of the more comprehensive ones are included in the Technical
`References (Appendix D).
`
`The Society of Automotive Engineers sponsors numerous technical meetings dealing with
`technological developments and problems in various types of automotive components. A
`number of volumes of conference proceedings have dealt with topics germane to SAl.
`These were acquired and are also listed in Appendix D.
`
`The Office of Defects Investigation (ODI) provided its entire database of consumer
`complaints of sudden accelerations as well as a sample of a hundred written complaints
`including correspondence and other attachments. Arrangements were made with the ODI
`Hotline to refer complainants with SAl problems in the Boston area to TSC for more
`extensive questioning and follow-up visits where interesting problems arose. Telephone
`interviews of approximately 20 owners and occasional field inspections of vehicles were
`conducted with these as well as a few other owners identified by other means.
`
`NHTSA's Vehicle Research and Test Center (VRTC) conducted extensive testing of
`acceleration and braking performance under various simulated fault conditions for a vehicle
`representative of each of the vehicles listed in Table 2-1 or a close substitute. These data
`are described fully in Appendix E. Determination of the susceptibility of certain cruise
`controls to malfunction as a result of EMI/RFI or environmental extremes was done at TSC,
`as described in Appendix F. Measurements of pedal characteristics were also done by TSC
`staff and are reported in Appendix G.
`
`Because of the unusually high rate of reported SAl in the Audi 5000, that vehicle has been
`subjected to much more intense scrutiny than any other. As part of TSC's work for NHTSA,
`a detailed analysis of the Audi 5000 was begun early in 1987. The product of that study is
`reproduced in its entirety as Appendix H. Where appropriate, the reader is also referred to
`sections of the Audi 5000 analysis in Appendix H for detailed engineering discussions.
`
`4
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`Ford Motor Company et al.
`Ex. 1007-017
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`An Examination of Sudden Acceleration
`
`3;0 TECHNICAL DISCUSSION AND CONCLUSIONS
`
`The following logical assumptions were used as the basis for the design of experiments and
`analyses:
`
`• SAl could be the result of a single primary causal factor or could result from
`the action of a number of factors which contribute to or increase the
`likelihood of an SAl.
`
`• Factors related to SAl occurrence can include power-train design, brake
`system design, and vehicle ergonomics (particularly pedal configuration).
`
`• An SAl must involve a significant increase in engine power, which could be
`caused by a failure in an engine-control system or a pedal misapplication
`(inadvertent depression of the accelerator instead of, or in addition to, the
`brake).
`
`• If the SAl begins with a vehicle-system malfunction, loss of control could
`occur through braking system failure or the driver's failure to apply the brake
`with sufficient force and/or the driver inadvertently pressing the accelerator.
`
`•
`
`If the SAl is initiated by a pedal misapplication of which the driver is unaware,
`loss of control can occur.
`
`• The location, orientation, and force-deflection characteristics of pedals can
`influence the probability that the driver will mistake one pedal for another.
`
`• If the cause of an SAl is an electro-mechanical or mechanical failure, this
`should be evident after the fact.
`
`• If the cause of an ·SAI is an intermittent electronic failure, physical evidence
`may be very difficult to find, but the failure mode should be reproducible
`either through in-vehicle or laboratory bench tests.
`
`• The vehicles studied mayor may not share the same causal and contributing
`factors.
`
`The study covered:
`
`• engines and their controls, aswell as transmissions, to determine whether and
`how they might produce unwanted power;
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`5
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`Ford Motor Company et al.
`Ex. 1007-018
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`

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`•
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`the role of electromagnetic and radio-frequency interference (EMI/RFI) and
`other environmental variables in stimulating malfunctions in critical engine
`controls;
`
`• braking systems, which were examined with a view as to how they could fail
`momentarily but spontaneously recover normal function