Toyota: Sudden acceleration test unrealistic

by Peter Valdes-Dapena, senior writer


NEW YORK (CNNMoney.com) -- Toyota is rejecting a university professor's test that claims to show that electronic throttle systems on Toyota cars could cause unintended acceleration saying the test was simply not realistic.

Dr. David Gilbert of Southern Illinois University performed a demonstration of how the problem could occur in an ABC News broadcast in late February. Later, Gilbert testified before a Congressional hearing looking into unintended acceleration in Toyota cars.

10 best cars: Consumer Reports
The influential magazine names the cars, trucks and SUVs it rates highest in popular categories.

"Dr. Gilbert's demonstration, as shown on the ABC News web site, amounts to little more than connecting three of the six pedal sensor wires to an engineered circuit to achieve engine revving," said Exponent, a research firm hired by Toyota, in a report obtained by CNN that was prepared for Toyota attorneys.

Some safety consultants have alleged that electronic throttle control, or ETC, systems used on Toyota cars are a likely cause of unintended acceleration problems. Toyota has said it is studying the issue but has not found any fault in the electronic systems that would lead to unintended acceleration in real world conditions.

Still, Toyota (TM) has recalled more than 8 million cars for mechanical problems including issues related to the gas pedals.

Gilbert said he had uncovered a potential for a short circuit that could undermine the electronic throttle control system's built in safety checks.

The system used on Toyota cars relies on two separate sensors connected to the gas pedal and another pair connected to the throttle valve itself. In order for the system to work, each sensor in a pair has to match. If they don't match in the proper way, an on-board computer immediately senses a problem and the engine power is reduced to idle or it's shut off altogether.

Gilbert said that he overrode that safety feature, allowing faulty pedal signals to go to the engine with no problem being detected by the car's on-board computer.

Exponent, the research firm hired by Toyota, was able to replicate Gilbert's results but says that the test presents an unrealistic situation that has virtually no chance of happening in the real world.

"For such an event to happen in the real world requires a sequence of faults that is extraordinarily unlikely," the report continues.

Exponent was also able to replicate the same sequence of short circuits, with the same result, in other automakers' cars, which would undercut the allegation that the problem would be somehow unique to Toyotas.

"Every vehicle from other manufacturers tested by Exponent could be induced to respond with a sudden increase in engine speed and power output," Exponent said in a fact sheet. "These demonstrations in no way indicate a defect with any of the vehicles tested (including the Toyota Avalon and Camry)."

A representative for Southern Illinois University said that Dr. Gilbert has already met with Toyota representatives and that more meetings are planned. To top of page

Frontline troops push for solar energy
The U.S. Marines are testing renewable energy technologies like solar to reduce costs and casualties associated with fossil fuels. Play
25 Best Places to find rich singles
Looking for Mr. or Ms. Moneybags? Hunt down the perfect mate in these wealthy cities, which are brimming with unattached professionals. More
Fun festivals: Twins to mustard to pirates!
You'll see double in Twinsburg, Ohio, and Ketchup lovers should beware in Middleton, WI. Here's some of the best and strangest town festivals. Play
Find Your Next Car
Index Last Change % Change
Dow 16,804.71 -238.19 -1.40%
Nasdaq 4,422.09 -71.31 -1.59%
S&P 500 1,946.16 -26.13 -1.32%
Treasuries 2.40 -0.10 -4.19%
Data as of 7:14am ET
Company Price Change % Change
Bank of America Corp... 16.82 -0.23 -1.35%
Ford Motor Co 14.59 -0.18 -1.22%
Facebook Inc 76.55 -2.49 -3.15%
Apple Inc 99.18 -1.57 -1.56%
Cisco Systems Inc 25.03 -0.08 -0.34%
Data as of Oct 1

Sections

In the last five years, pumpkin sales have risen 34% as people demand pumpkin in everything from beer to beef jerky. More

Facebook's chief product officer issued an apology to Sister Roma and the drag community on Wednesday for its flawed 'real name' policy. More

New York City launches a comprehensive site for all things related to its digital tech scene, Digital.NYC. More

For these seniors, the best retirement is not to retire. From a 102-year-old Wal-Mart worker to an activist park ranger, these workers have stayed on the job well into their golden years. More

Market indexes are shown in real time, except for the DJIA, which is delayed by two minutes. All times are ET. Disclaimer Morningstar: © 2014 Morningstar, Inc. All Rights Reserved. Disclaimer The Dow Jones IndexesSM are proprietary to and distributed by Dow Jones & Company, Inc. and have been licensed for use. All content of the Dow Jones IndexesSM © 2014 is proprietary to Dow Jones & Company, Inc. Chicago Mercantile Association. The market data is the property of Chicago Mercantile Exchange Inc. and its licensors. All rights reserved. FactSet Research Systems Inc. 2014. All rights reserved. Most stock quote data provided by BATS.