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 16,979.13 59.54 0.35%
Nasdaq 4,526.48 -1.03 -0.02%
S&P 500 1,986.51 4.91 0.25%
Treasuries 2.43 0.02 0.87%
Data as of 10:29pm ET
Company Price Change % Change
Bank of America Corp... 15.52 0.07 0.45%
Apple Inc 100.57 0.04 0.04%
General Electric Co 26.36 0.31 1.19%
Intel Corp 34.50 0.16 0.47%
Staples Inc 11.32 -0.30 -2.58%
Data as of 4:01pm ET

Sections

This month, Delaware became the first state to pass a law giving heirs the right to access the online accounts and assets of someone who has passed away. More

Median income is up 3.8% since 2011, though it's still down since the economic recovery began in 2009. More

Small business owners say the economy is still their biggest challenge, which keeps them from expanding and hiring, according to a CNNMoney-Manta survey. More

This month, Delaware became the first state to pass a law giving heirs the right to access the online accounts and assets of someone who has passed away. 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.