backtop


Print 54 comment(s) - last by lyeoh.. on Mar 31 at 12:50 PM

The tail of a comet is not suspected to be the cause of unintended acceleration

Toyota has been hit hard with widespread issues with its Prius and other cars that have suffered from glitches with brakes or unintended acceleration. Toyota was forced to recall a large number of its vehicles to install new parts to prevent wear of the throttle pedal that was the cause of some of the issues.

The last headline-making bout of unintended acceleration happened in early March when police in California had to help a motorist who was reportedly unable to stop his Prius from accelerating. 
Detnews.com reports that the U.S. Transportation Department has announced that it intends to launch a pair of major investigations that will seek to determine if vehicle electronics or electromagnetic interference are to blame for unintended vehicle acceleration incidents that have been rampant recently.

The investigations will be headed by the National Academy of Sciences and the other will be run by NASA. According to U.S. Transportation Secretary Ray LaHood, the investigations will not focus on Toyota alone and will focus on all manufacturers. So far, Toyota is the most affected of the automakers and the recall to fix issues with floor mats and throttle pedals has covered 8.5 million of the automakers vehicles so far.

Since 2000, a total of 3,000 complaints including 51 deaths have been linked to Toyota vehicles that failed to stop accelerating. Toyota maintains that EMI and electronics are not the cause of the issue and that trapped or malfunctioning pedals are the cause.

"Many members of Congress think it's electronics and I heard enough of that -- not only from members but from Toyota drivers ... and so we felt we really needed to get outside experts," LaHood said. "We are tapping the best minds around." 

Toyota added, "We expect they will bring a thorough and scientific approach to their examination of the issues. Separating fact from fiction can only be good for the motoring public and the industry as a whole. We are confident in our vehicles and in our electronics. We will lend our full support and cooperation to DOT and NHTSA as they moved forward."

The investigations will reportedly last 15 months and will seek to find and address any safety issues with any vehicle on the road today in America. All possible causes for unintended vehicle acceleration will reportedly be investigated including electronics, human error, mechanical failure, and interference with accelerator systems.

According to LaHood, the department will spend $3 million on the two studies including the cost of buying cars that have allegedly suffered from unintended acceleration. The NHTSA has brought in engineers and other experts for the investigations on topics such as electromagnetic compatibility among others in an attempt to determine if flaws in vehicles on the road warrant a defect investigation. The review of the Toyota electronic throttle control system is expected to be completed by late summer reports the NHTSA.



Comments     Threshold


This article is over a month old, voting and posting comments is disabled

By Chillin1248 on 3/30/2010 6:43:17 PM , Rating: 4
And to finish up his point, here are Toyota's findings regarding the runaway prius:

quote:
• The accelerator pedal was tested and found to be working normally with no mechanical binding or friction. It should be noted that the Prius is not subject to a recall for sticking accelerator pedals and the Prius component is made by a different supplier than the one recalled.

The front brakes showed severe wear and damage from overheating. The rear brakes and parking brake were in good condition and functional.

• A Toyota carpeted floor mat of the correct type for the vehicle was installed but not secured to the retention hooks. It was not found to be interfering or even touching the accelerator pedal.

The pushbutton power switch worked normally and shut the vehicle off when depressed for 3 seconds as the 911 operator advised Mr. Sikes to do.

The shift lever also worked normally and neutral could be selected. The neutral position is clearly marked and can be easily engaged by moving the lever left to the “N” marking.

• There were no diagnostic trouble codes found in the power management computer, nor was the dashboard malfunction indicator light activated. The hybrid self-diagnostic system did show evidence of numerous, rapidly repeated on-and- off applications of both the accelerator and the brake pedals.

• After examination of individual components, the front brakes were replaced and the vehicle was test driven, during which the vehicle was observed to be functioning normally.

During testing, the brakes were purposely abused by continuous light application in order to overheat them. The vehicle could be safely stopped by means of the brake pedal, even when overheated.


And finally:
quote:
The Prius braking system uses both conventional hydraulic friction brakes and a regenerative braking system which switches the electric drive motors into brakes to generate electricity.

The system features a sophisticated self- protection function which cuts engine power if moderate brake pedal pressure is applied and the accelerator pedal is depressed more than approximately 50 percent, in effect providing a form of “brake override.”

This function, which is intended to protect the system from overload and possible damage, was found to be functioning normally during the preliminary field examination.

Toyota engineers believe that it would be extremely difficult for the Prius to be driven at a continuous high speed with more than light brake-pedal pressure, and that the assertion that the vehicle could not be stopped with the brakes is fundamentally inconsistent with basic vehicle design and the investigation observations.


-------
Chillin


By lyeoh on 3/31/2010 12:50:35 PM , Rating: 2
If it's that Sikes guy you are talking about , unless there's lots of bad reporting, apparently he claimed to have reached down with his hand to pull up the accelerator...

He was repeatedly told to shift to neutral but refused because he claimed he thought it was unsafe, and yet he still dared reach down and try to pull up the accelerator while his car is speeding along?

Toyota cars _might_ have "unintended acceleration" problems, but that guy is unbelievable.

On the other hand the case of Juanita Grossman prevents me from confidently blaming the drivers and saying it's not Toyota's fault. Perhaps Grossman did screw up at first, but who knows, the evidence has gone cold or has been destroyed.


"Vista runs on Atom ... It's just no one uses it". -- Intel CEO Paul Otellini














botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki