Join Junko Yoshida and other EE Times editors on Wed. Nov. 6 at 1PM ET (10AM PT) for a live chat about the Toyota unintended acceleration cases and why they are important to you as consumers and engineers.
Click here to join Junko Yoshida and EE Times editors in a live chat on Wednesday, November 6 at 1:00 p.m. ET (10:00 a.m. PT), about Toyota's unintended acceleration cases. You must be registered and logged into EE Times to join chat.
Many of us, general consumers, EE Times readers, and editors included, for a long time mistakenly believed that Toyota's unintended acceleration cases were "over" when the Japanese car maker ordered massive recalls of some of their vehicles on the grounds of incorrectly placed floor mats and stick pedals.
Well, it turns out that Toyota's problem hasn't been swept entirely under the floor mat.
A case in Oklahoma (Bookout v. Toyota) could change the way the unintended acceleration issue (many are still pending) is argued and tried in the future.
What's the big deal about the Oklahoma case?
It's a big deal because the plaintiffs' attorneys, for the first time, put the fault squarely on a flaw in the vehicle's electronic throttle control system. This is also the first case in which a real jury lasted the whole trial, heard the evidence, and delivered a verdict. Finally, the Oklahoma jury verdict is the first time Toyota was found liable since the company started recalling millions of vehicles in 2009.
Michael Barr, expert witness in the Oklahoma case, described the Bookout v. Toyota case, as follows:
The accident happened while Mrs. Bookout and a passenger were exiting from a highway, in Oklahoma. The exit ramp was about 1000 feet. Initially, the 2005 Camry slowed some as she started to exit. But then the car would not slow down. Mrs. Bookout pumped the brakes and tried more braking with no effect. Her passenger suggested trying the parking brake. The parking brake is believed to be cause of 150 foot skid mark at the bottom of the exit ramp and across the intersecting road into a ditch-hill impact. The passenger died later of her injuries.
Toyota's defense was she stepped on the gas not the brake earlier on the ramp. But even their reconstruction expert said by the start of the skidmark she was on the brake pedal. Toyota disputed that the parking brake was used, but that didn't seem to fit the physical evidence of the skid mark.
Bottom line: If the throttle was closed, her 2005 Camry should've stopped in <100' no matter what was going on before that. But after the 150' skid mark she was still going ~25mph.
You have read in EE Times, in excerpts of the trial transcript, some of the details of how Toyota's software failed to control the electronic throttle system.
The following video clip by Consumer Reports could help you understand the issue further.
Toyota's power brakes are indirectly linked to the software that controls the throttle. Barr pointed out, "When the throttle is open more than about one third, so much air rushes toward the vacuum in the next cylinder to fire that the power brake vacuum does not replenish after you pump the brakes even 1-2 times." Indeed the driver in this Bookout case testified she pumped "6 or 7 times" between when the car began to accelerate and when she tried just pressing solidly on the brake pedal and then adding the parking brake.
Join Junko Yoshida on EE Times live chat at 1:00 p.m. ET (10:00 a.m. PT) on Wednesday, November 6.