Toyota’s Unintended Acceleration Problem Still There – Recalls

It’s been a few years since we had a bunch of attention of the unintended acceleration problem that Toyota had with many models in the U.S. and now being almost 2014, we see Saudi Arabia and South Korea forcing recalls on the cars for the same problem.

Back when this problem first surfaced, I did a bunch of careful talking on the subject. Why so careful…  Lawsuits !

I never actually  spelled out the cause. I spoke in generalities and spoke of the general clash of RF generating tech in our increasingly data controlled world. To speak specifically, I needed a test vehicle that had the problem so I could test my “THEORY”. No such affected models were in my area and I could not get co-operation of dealers that were 20 miles or more away. So I will now speak to the issue in “detail”  but still as a theory.

Like any science, the thing that makes the most sense, is normally correct but to understand this problem, you need to have a background in Radio Electronics, Digital Radio, Computer Data Communication and Computer Electronics.

Weird as it may be, these all have been hobbies of mine starting at the age of 11 in electronics and 20 in computer electronics and data/communication and a radio ham for 25 years and I’m over 50 at the time of writing this. OK,  I just wanted you to have a feel as to why I understood this as I have had to troubleshoot various rf interference and even digital rf interference on my many projects.

First the up-to-date:

More recalls in Saudi Arabia and South Korea years after the issue was thought to be dead.

http://www.4-traders.com/TOYOTA-MOTOR-CORP-6492484/news/Toyota-Motor-Corp–Toyota-recalling-more-than-400000-vehicles-in-Saudi-Arabia-17662939/

http://english.yonhapnews.co.kr/business/2013/12/23/0501000000AEN20131223000600320.html

http://www.japantoday.com/category/business/view/saudi-arabia-recalls-400000-toyotas-over-acceleration-concerns

Now with that let me explain in more plain English what exactly I thought was happening and how I think they fixed the problem in the United States were they did the Recall a few years ago. I am sorry if some do not understand this.

In Toyota’s case, I believe that GSM (used by AT&T and T-Mobile) cell phone data was being parasitic to the data line in between the console area of the cockpit and the vehicle computer.

This is a line that is expected to transfer binary data as the settings of the user instruments in the cockpit are digital or digitized analog data in nature and are simple low speed data to the ECM (computer).

The cell phone and vehicle computer do not speak the same language or talk at the same data rate. But occasionally a data string would be recognized as a command and act on it.

What made this still a bit baffling to me, and I did not think about it until after the original post I had made on the topic, was why user intervention was not stopping the acceleration. As I was later watching Toyota’s fix for this included a firmware update the solution came to me. What was in the update for the computer?

First let me explain something about micro-controller development as it is a bit like writing game programs on a PC (just for a example some may relate to). As the program gets to complicated for the developer to test things out without the need to go through all the steps of the program to test just one area or function, you need to create shortcuts or “backdoors”.

So  it was this “backdoor” that seemed to be getting the interfering data to do things like (for example only) set the engine rpm to 3,000 rpm OR Force the cruise control at 60 MPH (for test in the lab for MPG tests etc). And if these backdoor engineers command sets were active, user intervention would not have been something the original code would have allowed for. So once active would be active until a engineers command came through to stop what it was doing or cancel the last command.

The entire problem was 2 fold.

1 The design engineering did not close their testing “backdoor” in the final product. By itself would not have been a problem except for –

2 The data lines in the cockpit area were not resistant to the parasitic nature of near-field GSM data communications found in cell phone from carriers like AT&T and T-Mobile.

Toyota’s fix, no doubt, was just to close the engineers “backdoor” and possibly add a string of code that allowed user intervention in the case it got there anyway.

Most likely the way they did it,  as some of the options were probably used by dealerships in diagnostic testing to remedy problems reported by owners by specially designed equipment.

In any case what I have been saying is still true. We are probably going to experience more of this sort of weird stuff as this clash of Tech is just getting started.

In my original research on this issue, I had read a bunch of NTSB complaints.  One item that was reported frequently that I though I could explain is not on the NTSB’s radar and it was this.

Many folks were reporting hard to steer or not able to steer and many were reporting accidents because of it.

So I look for similarities of each incident and found that the cars involved all had electronically assisted power steering (every car maker has their own term for there car but that is what it is).

Well, electronic power steering is just a way to do away with the mechanical power steering pump and get some horse power savings that translate into fuel savings. They could have done this stuff a long time ago and it’s a good idea. After all, you don’t need a pump running all the time when traveling as you really turn very little. Using electric motors only when needed just makes sense.

To control such a system, you need a sensor in the steering wheel to know if the driver is turning the wheel and in which direction and how fast . This would give the appropriate data to know how much assistance to apply to the steering assembly and what direction to apply it.

Having read many of these, the problem/solution did not hit me until I read one for the 3rd time as it was similar to another. The cars were attempting to overtake a tractor trailer on the interstate when the steering became hard or impossible to control.

BINGO…   I understood right away.

Many truckers use CB radio which operates on a frequency of 26/27 MHz and has a wavelength of 11 meters. but more importantly, most truckers use amplifiers, actually illegally, but because of cutbacks in the FCC budget, nobody to enforce the rules so it is a common practice to use them and talk further down the highway.

The problem in this issue is that the strong RF signal is bombarding the sensors in the steering column and by falseing them, it’s telling the computer to steer hard in left and right at the same time. This makes it either difficult or impossible to steer.

I really doubt if the NTSB is not smart enough to figure this stuff out. So I think they have  answers like what I just said here but play a game with the manufactures to push them into doing something about it without alarming the public in general. Probably because it is tough to prove a case so far that it indeed caused the accident. To do that without being in a lawsuit would be a hard line to walk.  I realized that when I started writing and speaking on the issue.

Since GSM is the most popular format for cell phones in the majority of the world, it only makes sense that the other country’s would probably have more of a problem with this than we did.

So here it is that other countries having the problem have had enough problems to force a recall of the vehicles.

As Paul Harvey might say, Now you know the rest of the “untold” story.

If you would like to see my original Post on this (other site) please go here…

http://themidnightengineer.com/category/theory/unwanted-acceleration-theory/

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