Toyota to recall Lexus GX over rollover issues

By Daniel Chubb - Apr 19, 2010

After our recent reported “Don’t buy” warning regarding the Lexus GX 460, Toyota is finally about to announce a recall which according to a report from AutoBlog will involve around 5,000 vehicles currently in use.

The recall will affect 2010 Model-Year Lexus GX 460’s in a bid to rectify potentially dangerous handling characteristics during hard downhill braking. During this situation the traction control is said to allow the rear of the vehicle to step out further than is safe, which in turn could lead to the vehicle rolling over. Lexus dealers will be instructed to install new updated traction control software to combat this issue.

This latest recall joins the long line of Toyota problems over the last few months. This time however it would seem that the Japanese car manufacturer has acted quickly enough for the department of transportation regulations, as we doubt even Toyota could take another hit like the $16.4 million fine they recently agreed to pay for failing to act swiftly enough from the last recall. When will Toyota’s luck change? follow the link to read the full press release.

Source: The Detroit News

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Also See: Lexus GX460 sales continued: New software available


    The problems with the GX460 Stability Control System recently reported by Consumer Reports and actually acknowledged by Toyota simply have to be in the software, operating through various hardware components already on board. More and more responsibilities have been placed on these basic hardware items, mediated through computers, or as Toyota is careful to say, “electronics” and Toyota simply has not handled the integration of all these items very well and now many Toyota products, particularly the Prius, are beginning to look more and more like SOUTHERN ENGINEERING, beneath whatever slick veneer Toyota has managed to place around them. So Toyota is now going around the country with a certain laptop computer, which they claim is the only computer in this country with the software program capable of downloading and reading all the data in the Toyota electronic systems and that it is not offered more broadly or publicly since they claim the programs are experimental and unreliable and still under development etc, and lots of verbiage about how only several seconds of data are captured anyway and only if the airbags are deployed etc. Yet they show up all proud and pompous to study the Sipes Prius in San Diego and the Prius in Harrison NY and pull miraculously all sorts of data in both cases including the whole 20 minutes from the Sipes Prius and in the Harrison NY case they seem all anxious about how much data will be retrieved and then seem tremendously gratified in the second case about how much data was retrieved, indicating to skeptical observers that they were prepared to gloss over any data in either case that did not fit their agenda.

    Toyota in its defense of the Prius has always maintained that there is no defect in the electronics, and by extension in other vehicles in their lineup including the Lexus, since their testing has shown no defects. But this is clearly bogus and hardly anybody with any knowledge of computers has bought into it. If Toyota itself believes any of it, it would indicate MAGICAL THINKING on their part, that merely thinking something is perfect makes it perfect, or that thinking some problem has been solved makes it go away.

    “Safety Features” as used below indicates (1) ABS or anti-lock braking to shorten stopping distances and maintain steering control on slick surfaces. (2) Traction Control to reduce drive wheel spin on slick surface and improve steering control. (3) Stability Control to prevent dangerous situations related to “under-steer” or “over-steer” and skidding or tendency to over-turn during turns and other maneuvers.

    The hardware items involved in the “safety features” include (4) valves in the ABS brake control unit to increase or decrease or hold braking forces in each wheel mediated by computer commands (5) speed sensors on each wheel (6) yaw sensors in two planes at right angles to each other detecting G-forces (accelerations/decelerations) in multiple planes (7) steering angle sensors to indicating steering wheel position to help judge driver intent. (8) ECU Engine Control Unit to increase or decrease engine speed. Note that the ECU is often called on by the system to reduce engine power but this necessarily requires that it be able to restore or increase engine power. (9) special radar unit in the Prius acting through hardware and computer programs to maintain proper distance behind other vehicles, based on traffic speed by increasing/decreasing distance as seems appropriate to the system. (10) Computers to integrate all of this, implying that these computers must be spot on to avoid dangerous mistakes. (11) Clearly missing in all this are ways to collect data in sufficient detail to allow careful study of the system over long periods of time, to study each component in relation to all the others whether a fault is suspected or not. This implies good graphics programs allowing easy study of the data.

    So a lot of SAFETY FEATURES have developed from modest beginnings, based on a few basic features in hardware, and enabled by increasing computer power. There is nothing wrong with the basic concepts behind these “safety features” if they actually work and if they actually increase safety. It is my view that we should continue to evaluate all these “safety features” in real time to evaluate their continuing usefulness. For example some studies indicate that overall ABS anti-lock brake systems do not improve overall collision and fatality experiences, with improved safety confined to multi-vehicle accidents with less safety in single vehicle accidents and this leads to the suggestion that perhaps ABS systems lead to more aggressive driving. But suppose that we subject that to critical analysis. ABS units are commonly installed along with Traction Control Units and Stability Control Units, all operating through the same basic hardware and software. Random faults in any one of three systems could be causing accidents without calling specific attention to themselves. Suppose that we had sophisticated Data Recorders capable of recording perhaps 100 channels of data, each at twice per second with increased capture rates in burst mode occurring with sudden changes in any parameter. These would be comparable to the units in jet transports capable of capturing over 700 channels of data at comparable rates but the ones in automobiles would be much cheaper due to less requirements for crash survivability and due to economy of large scale production etc. These Data Recorders could hold large amounts of data in internal memory and plugging a laptop computer into them via a USB cable would have them show up as just another external device from which data could be downloaded, just like digital cameras are handled. Or they could in addition store data on data cards such as the CF Compact Flash cards. These CF cards now cost about $3 per GB (up to 32 GB) and are quickly becoming cheaper and larger. There would be universal programs which would allow various displays of the data, such as graphics displays of all driver inputs along with responses of the brakes, throttle etc. These sets of data could be accessed at random moments for routine study or after suspicious events. Completely unsuspected inappropriate responses of brakes and throttle etc, causing no symptoms, might be detected just on casual observation of the video. Plus allow careful study of any suspicious events. This would be enhanced by good graphics programs, simplified by the vastly increased power of modern computers with high speed graphics cards. Data could be easily shared with other enthusiasts. There is no evidence that Toyota is engaged in any of this and their constant claims that there is not possibly any defects in their electronics comes across as decidedly anti-intellectual.

    For example consider that both the Traction and Stability Control Units in the normal course of events go around casually applying brakes to one front wheel or the other as deemed appropriate, but if this somehow occurs unexpectedly with nothing suggesting that it is about to happen, it can lead to an uncontrollable turning motion, a force irresistible even if the driver knew it was coming, leading to swerving into another lane of traffic or completely off the road for example, especially dangerous if occurring out of the blue or during some other maneuver. The driver might not even recognize that such an event had occurred and police investigators would not even believe him even if he claimed it had occurred. Note that numerous Prius drivers have claimed this swerving motion happened to them and they all seem quite mystified by it, and seem not to have considered the basic feature of their electronic systems that would have made it possible. This may have happened to drivers of other brands of automobiles as well, but the Prius groups spend more time going into all sorts of mystifying things that have occurred to them, yet they seem to resist inputs from non-Prius drivers and people casting doubts about the Prius seem to have their rights to log on and comment quietly cancelled.

    Many of the faults of which Prius owners complain online seem to be software related, but reading through lots of these posts reveal little if any attempt to define what the mechanism of the fault is. One would like to develop the simplest theory which explains all the known facts and to make predictions which could be tested by experimentation.

    The Federal government requires that the newest jet transports monitor a minimum of 88 definite parameters in their “black boxes” but actually the manufactures have gone far beyond this, monitoring over 700 channels of data in the latest models, including lots of data from the engines, positions of controls in the cockpit, position of control surfaces, lots of data at intermediate points etc. In general these systems are designed to sort out intended from unintended (un-commanded) events (among other things.)

    Data recorders are not mandated in automobiles for two more years but the Big 3 are generally installing them anyway and making readouts easily available to all interested parties whereas Toyota is holding on until the bitter end and will not have them until 2012. Flight data recorders in airplanes monitor over 700 channels of data typically several times per second, with much higher rates in burst mode if sudden changes are detected and typically record 17-25 hours of data. The requirements for automobiles are much less rigorous and not well described online. NHSTA has mostly been standing quietly by, waiting to see what the car manufacturers would do on their own. Good luck NHSTA, we are proud of you.

    If Toyota really wanted to prove all its assertions about its electronics it would install data recorders capable of storing data for many hours from all significant sensors already on board as well as all commands issued to the hardware items. This would include all the signals (commands) to the brakes (pressure increase, decrease and hold) signals to the throttle and how these commands correlated with driver inputs from the gas pedal and the brake pedal etc. One should keep in mind that all commands to the throttle and brakes are merely “requests” since all systems are “fly-by-wire.” To repeat, there is no mechanical connection of the gas pedal or the brake pedal to the respective modules in the engine compartment.

    Good data collection is increasingly feasible since digital memory is dirt cheap and getting cheaper, as well as coming in larger and larger capacities. Various “safety features” such as stability control will be mandatory in 2013, so it seems reasonable to establish ways to ensure that it is actually doing something for us. Perhaps supposed increased safety on the roads is due to over-zealous police action rather than any safety improvements in vehicles. This means that lots of problems caused by electronic “safety systems” can easily go undetected amid all the noise. Meaningful analysis requires breaking out the actual numbers, to place blame or credit where it belongs.

    The ABS has yaw sensors to detect skidding sideways & speed sensors on all four wheels to prevent brake lockup, improving both stopping and steering . The ABS operates on slippery surfaces by using valves in the ABS brake control unit to increase and decrease braking forces at each wheel up to 20 times per second, yielding its familiar pulsation. The ECU simultaneously operates to reduce engine power as needed and this requires the ability to restore or INCREASE engine power when appropriate.

    So next consider TRACTION CONTOL, which acts by detecting the drive wheel that is spinning the most and applying a braking force to that wheel, sending more power to the other wheel with less spin due to better traction and reducing engine power as part of the total effort. Note again that the system must be able to INCREASE (restore) as easily as it reduces engine power,

    STABILITY CONTROL operates through the
    Further, Toyota in its Prius model has this cute little feature that uses radar to help control the distance from the vehicle in front. Again one can see that the system must have the capability of either decreasing or INCREASING engine power and thus vehicle speed to get this done.

    So we have all these neat safety features which depend on many different things operating perfectly in concert, controlled by computers, which must be operating without error. Notice that all of these features have the requirement of both decreasing and increasing engine power and vehicle speed. This provides the perfect mechanism to explain all the episodes of unintended acceleration UA that Toyota continues to deny, except to invoke bogus explanations like gas pedal entrapment under the floor mats and issues of stuck gas pedal which can be cured by inserting a magic little shim. These two explanations for UA meet with little acceptance outside of Toyota itself and those who seem to be their fan boys.

    So my point is that all these software issues now interact with all the basic hardware features already on board to produce the PERFECT STORM for Toyota. So there was the well-publicized San Diego case of James Sipes, with the wild 20 minute 30 mile chase down the freeway, followed shortly by the case in Harrison NY where a Prius underwent UA from a standing stop and struck a stone wall. These two cases, the first at high speed and the second from a standing stop simply indicate to me that the PRIUS IS UNSAFE AT ANY SPEED.