[Quietcars] Could electronics be what's causing runaway cars?
Chip Hailey
chiphailey at cableone.net
Wed Feb 24 14:04:19 UTC 2010
Could electronics be what's causing runaway cars?
By Jayne O'Donnell, USA TODAY
Allegations of unintended acceleration by
Toyota
models that are not part of the recall and by cars from other automakers
have revived
debate over whether electromagnetic interference is the cause of such
incidents.
The theory is that electrical signals - from sources as diverse as
cellphones, airport
radar and even a car's own systems - briefly and unpredictably wreak havoc
with sensitive
electronic controls in vehicles. It's an argument trial lawyers and consumer
advocates
have made for years.
How electromagnetic interference may affect cars
Cellphones can cause car trouble
Automakers contend that vehicle systems are designed with sufficient
shielding and
redundancy to prevent such malfunctions. They have tested for
electromagnetic interference
(EMI) and found no evidence of it for as long as plaintiff lawyers have
blamed it
for crashes. Several acceleration suits filed against Toyota claim an EMI
link.
It's virtually impossible to prove EMI caused a crash. Plaintiffs have won
just one
case arguing that issue alone. But there are enough unexplainable crashes
and acceleration
incidents to keep the door open to allegations.
The National Highway Traffic Safety Administration now is investigating
whether EMI
could be a factor in Toyota's sudden-acceleration problems. It is NHTSA's
first serious
look at EMI in decades, and members of Congress will explore it in Toyota
hearings
beginning today.
"If these congressional hearings probe deeply enough, they'll discover that
the car
industry has known from the beginning that the most likely cause of sudden
acceleration
is internal electromagnetic interference,
" charges Tom Murray, a Sandusky, Ohio,
attorney who has brought dozens of acceleration lawsuits and is writing a
book on
sudden acceleration.
Toyota, however, says floor mat interference and sticky gas pedals are the
causes
of unintended acceleration in the more than 8 million vehicles it has
recalled in
the USA for either problem. It commissioned an outside company, Exponent, in
December
to look at the electronic throttle controls, which have replaced mechanical
gas pedal
and throttle systems in most vehicles of all makes since the 1990s.
According to a draft report obtained by USA TODAY, Exponent says it could
not induce
unintended acceleration through "electrical disturbances."
But Keith Armstrong, a United Kingdom-based EMI expert, argues that the
tests weren't
comprehensive enough to find whether EMI could be to blame. Two experts
consulted
by the House Energy & Commerce Committee, which is holding today's hearing,
were
similarly critical. The panel's leadership called it a flawed report, but
Toyota
says it is far from final and will be peer-reviewed.
NHTSA says it "has no reason at this point to believe" EMI is causing
unintended
acceleration in Toyotas. Still, looking at it anew is a turnabout. In 1975,
a NHTSA
report warned that EMI was a potential problem as electronics, just then
being used
in cars, became more common. Since then, however, its acceleration studies
concluded
that driver behavior was to blame and didn't address EMI.
Murray, who says he was contacted by NHTSA defect investigators last month,
believes
that is a mistake. He blames EMI for all but "1% to 2% of all Toyota
sudden-acceleration
cases" and most of those in other vehicles, too. At least 14
sudden-acceleration
lawsuits alleging EMI are pending, including ones against Toyota.
Onboard EMI sources
While EMI from external sources, such as traffic lights or radar, is
possible, it
is unlikely because it would require an unusually strong signal, says Brian
Kirk,
a U.K.-based consultant in software safety systems who advises in auto
lawsuits.
More likely sources are onboard components, he says, because even very
low-power
electromagnetic radiation from the car's electronics could cause a problem.
He says,
for example, that EMI from poorly designed ignition wiring could disrupt
signals
in the electronic throttle or engine controls.
Internal EMI has been linked, Armstrong says, to high-voltage spikes when
current
in a wire or coil is switched, such as when the headlights or brake lights
go off.
Automakers' move to electronic engine controls, including throttles, has
been driven
by the need to meet tighter federal fuel and emissions regulations. They
allow far
more precise control of the engine operation and fuel use. Recent years have
seen
so-called drive-by-wire systems replacing mechanical control of other
critical functions,
such as steering assist.
Automakers' quiet concerns
Testing for potential EMI is a closely guarded subject within automakers.
But lawsuits
over the years have uncovered documents citing internal concern.
Walter Gelon, then an employee at General Motors-owned
Hughes Aircraft
, warned in early 1987 that he thought EMI was behind reported unintended
acceleration
in GM vehicles, according to an internal memo obtained by Murray's law firm,
Murray
& Murray.
"It seems very clear to me that (GM) vehicles have serious EMI problems
which are
triggering ... unwanted acceleration,
" Gelon wrote to Hughes colleagues.
But a late 1988 report provided by GM showed Hughes largely ruled out EMI as
a cause
of sudden acceleration after a lengthy GM investigation.
GM still holds that position. "GM has a robust testing and validation
process for
electromagnetic compatibility (among systems), and there is nothing past or
current
that suggests any unwanted acceleration issues related to EMI in our
vehicles," says
spokesman Alan Adler.
Also in the 1980s, as use of electronics in cars expanded fast, EMI was on
the minds
of Ford engineers. The minutes of an October 1986 Ford Technical Affairs
Committee
meeting, provided by Murray & Murray, show Ford looked into whether
"electromagnetic
influences" were behind an increase in unexplainable electronic component
failures.
Spokesman Said Deep said Ford later ruled out "electrical interference
problems"
and gave dealers better diagnostic equipment and training, which reduced the
number
of such warranty claims.
Armstrong, who was interviewed this month by NHTSA defect investigators,
says "automakers
almost never publicly acknowledge EMI problems," but he remains sure they
exist.
"Why would (automakers) spend millions of dollars on sophisticated EMC
(electromagnetic
compatibility) test facilities, and place EMC test requirements on all their
electronic
suppliers, if it wasn't necessary?" asks Armstrong, who is president of the
U.K.-based
EMC Industry Association. He was an expert witness in a Ford
sudden-acceleration
case this month and is advising lawyers suing Toyota.
Armstrong reviewed the Exponent draft report on Toyota's electronic
throttles and
called it "complete baloney." He asserts that the "redundant" backup sensors
the
report suggests protect against EMI are ineffective because they are based
on the
same technology. He believes two different technologies must be used to keep
multiple
sensors from being affected in the same way at the same time.
Dozens of EMI testing centers
Automakers say they try to test for all possible electronic signals that
could affect
cars. There are dozens of EMI auto testing facilities in the U.S. and
Mexico, including
centers owned by GM and Ford.
Lee Hill, founding partner of Silent Solutions, which does EMI testing and
consulting
on autos says, "Anything with electronics has some vulnerability, but every
important
system on an automobile is tested very carefully."
Hill says automakers have been testing for EMI since the 1960s, even before
electronics
controlled vital systems. He says that in addition to testing of onboard
systems,
vehicles are bombarded in a lab with external radio waves and driven through
areas
where there is known radio-wave interference.
Ford's Deep says: "We have not seen issues from EMI or any other signal
disturbances
from external sources. We do also test extensively and rigorously for
internal sources.
Ford vehicles are designed to prevent unwanted acceleration by protecting
against,
detecting and evaluating electrical interferences."
Toyota is building an EMI test facility in Ann Arbor, Mich., and already has
one
in Japan.
"We have never found ... any issue of acceleration from the electronics,
" Kristen
Tabar, general manager of electronic systems for Toyota Motor Engineering
and Manufacturing,
North America, said Monday during a briefing for journalists on Toyota
electronics
testing. "If interference did occur beyond what our testing would have
found, (the
system) would detect it and act appropriately."
Toyota President Akio Toyoda said last week that its cars have "fail-safe"
systems
that shut the cars down when electrical interferences occur, a feature
auto-engineering
experts say is now standard in the industry.
Proving anything is tough
Certainty may remain elusive.
Mukul Verma, formerly one of GM's top safety experts, points out that
electronic
throttle controls may be affected by other electrical and electronic
systems, including
those in the car, and that unintended acceleration may result from car
sensor malfunctions,
software glitches or from "electromagnetic interferences, which are random
and still
not fully understood."
Verma, an adjunct professor of mechatronics (the relationship between
mechanical
and electronic components) at Lawrence Technological University in
Southfield, Mich.,
points up the difficulty in being able to "rule in or rule out" EMI as a
factor in
sudden acceleration. "It's just too hard to prove either way. The thing with
electrical
currents is, once they are done and gone, there's no trace level. You can't
reconstruct
any phenomenon caused by electrical current going into a computer."
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