Motor Crave:British Engineering Consultants Point to Electromagnetic Interference In Toyota Problems

[Omaha Steve]

http://motorcrave.com/consultants-point-to-electromagnetic-interference-in-toyota-problems/5927/

Consultants Point to Electromagnetic Interference In Toyota Problems

Thursday, March 25, 2010 10:00AM - By Chris Weiss

Toyota has been pretty insistent that the cause of unintended acceleration within its recalled vehicles is not and never will be due to electronics. A group of British engineering consultants disagrees and believes that electromagnetic interference in the electronic throttle-control system is the cause of the problem. Parts of the throttle system and pedal assemblies are not shielded from interference, according to the engineers. They also stated that Toyota’s intended fix, a brake override system, will not be effective in addressing the issue.

Providing a little slice of save-face for Toyota, the consultants also say that the interference is difficult to detect. One of the consultants said that automotive tests do not sufficiently cover EMI.

A spokesperson for Toyota presented doubt on the hypothesis stating: “Toyota has sold more than 40 million cars and trucks with our electronic throttle control system (ETCS) and we are very confident that the system is not the cause of unintended acceleration.”

If I were Toyota, I wouldn’t be talking that confidently about anything.

[Warpy]

1. Nothing as relatively rare as the acceleration problem

is going to be easy to pin down. Their best bet is a black box system in the car that documents everything that's going on with the electronics before and during such an event, a system like the black box system in planes that covers the last half hour of flight, only.

That's going to be expensive to do, but it's likely the only thing that is going to tell anyone what the problem is. Other than that, it's going to be trial and error and unless they get very lucky, a very long process.

[tech9413]

2. Agreed, I spent years trying to find the cause of failures

electronic systems, especially those with computer/software control are prone to failures that are hard to pin down. The sad part is that manufacturers are too tight lipped until they can duplicate the failure and understand why it happens. I was on the ground trying to solve the problems but they wouldn't share the information to help solve the problem.
In the meantime, customers pay for repairs that are a fault of design and support staff are left to look like fools because they can't solve the problem.
It's no wonder I'm not excited about going back to work.

[JBoy]

3. I could easily see EMI being the root cause of this.

Would explain the randomness between vehicles of the same type, as well as within the same vehicle.

Probably time to start applying some MIL-STDs to auto design.