SANTA MONICA, California — Toyota's most recent throttle-related recall has to do with the throttle pedal assembly. This assembly consists of the actual pedal itself, a hinge, an electronic pickup that measures how far the pedal has been pressed, a strong "return spring" that pushes the pedal back to zero when you relax your foot and, finally, a damping mechanism intended to give the pedal a "natural" feel by taking the edge off the spring's tendency to snap the throttle pedal up alarmingly. This mechanism is similar in intent to those that prevent doors or kitchen cabinets from slamming shut and making a nuisance of themselves, but on a far more subtle level.
It is this damping mechanism that is at the root of the problem. Over time, the friction of the mechanism may get too high and cause the pedal to hang up or return too slowly. Time, temperature and humidity conditions are thought to affect whether the problem develops or not, but the exact worst-case combination of these factors has not yet been pinpointed.
But not all pedals are susceptible because the internal details of how the damper is laid out differ slightly between the two parts suppliers that supply throttle pedals to Toyota, Scion and Lexus assembly lines. In general, Denso of Japan supplies throttle pedal assemblies for Japan-built vehicles, and CTS supplies the parts to vehicles built in the U.S. and Canada. It's a simple matter of logistics and shipping costs.
Scion and Lexus vehicles are not on the recall list simply because these cars are imported from Japanese plants where Denso pedals are exclusively used. The one exception is the Lexus RX: It is built in Canada, but the pedals used there reportedly come from Denso.
The Toyota Avalon, Matrix, Sequoia, Tundra and the Pontiac Vibe are/were built exclusively in North American Toyota plants. If the model year matches the range specified in the recall notice, these cars and trucks absolutely will have the CTS pedal assembly in question.
Camrys, Corollas, the RAV4 and the Highlander can either be built in North America or imported from Japan. Those built in Japan use the Denso pedal assembly and are not subject to the recall; those built in North America use the CTS pedal and are included in the recall. Japan-built models will have a VIN starting with "JT" while North American-built cars will start with a numeral instead of the letter "J."
But the Camry case is a bit more complicated. So many Camrys are built in the U.S. plant that both Denso and CTS pedal assemblies are used to maintain the supply. The Camry Hybrid and Japanese-built "JT" Camrys do not use the CTS pedal in question. Some U.S.-built Camrys use Denso, while others use CTS. For the Camry, an inspection by a dealer is needed to sort it out.
It's worth noting that the detail dimensions of these pedal assemblies (throttle pedal length, the angle at which it protrudes and attaches to the car, and other factors) will differ subtly between each listed vehicle. A Denso pedal from a Lexus ES 350, for example, may not fit in an affected Corolla.
Inside Line says: Need more clarity? You're not alone. While it might seem simple to determine if your Toyota vehicle is affected by the recall, it's best that consumers consult the list of VINs (vehicle identification numbers) released by Toyota to make certain. — Dan Edmunds, Director of Vehicle Testing
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peterwg64 says:
04:20 PM, 02/03/2010
In fact, Toyota Japan just annouced recall Prius 2010 for brake's problem.
Thats the exactly same problem I experienced months ago on my Lexus ES330 2005: braking system won't work at low speed on slipping or icy road. it resisted against my super strong pressure in order to stop it. I understood it was ABS taking the control at the moment, but it should not take effect at low speed, right ?
Another problem is when making a turn on slippy road, my Lexua frequently skid a couple of feet and sometimes it even spin 30 degrees.
It was made in Japan with VIN staring with a "J" and it was cableless pedal.
Let's go back to the so called unintended accecelation recall.
I had a Toyota Camry 1998 model. It had a feature from day one when I purchased it. After accelerating it to my expected speed, when I move off my foot from the gas pedal, the Camry can keep running at the expected speed for a couple of miles. It will stop slowly if I press the brake gently. I can immedaitely stop when I press the brake hard. It is a good feature since it saves my energy and the gas too. It already had the brake override gas pedal mechanism. But looks like recent models faild to duplicate this good feature after moving to cableless pedal system due to inabily in firmware, right ? or cost saving ?
ara3 says:
05:21 AM, 02/03/2010
The current updates on "possible" computer problems is very interesting. I have a Lexus GS and it, too, has problems. Not safety concerns fortunately, but listening to today's news updates on possible computer glitches in the Prius where the car accelerates on its own (possibly connected to the cruise control), the report sounded so familiar: no one to contact, no one listens, no admission of a problem, nothing. Same for me. Systems on my Lexus just stop doing what they normally do, and it's unpredictible and random. When the big guys at Lexus decided they couldn't fix the now documented problems, they told the dealer that it's normal. For me, no one to contact because the Lexus people only contact the dealer and put me into an endless loop. Arbitration, they told me, is the only avenue I have. So, that's now scheduled. Systems shut off, go to manual, things just stop working. Now, we are told that this is normal, but no one knows why, how, or what the rationale is. Reason: they made it up to (hopefully) shut me up. They must think we are stupid. Wrong
wyounger says:
07:29 AM, 01/29/2010
@sparkplug8:
You read right, there is no mechanical connection between the pedal and the engine anymore. This is the case more often than not on all cars built after around 2003, and almost all new cars. The sensor and circuits are designed much like what you find in an Airbus plane, with redundancy and failure detection built in. The problem in this recall is a mechanical aspect of the pedal assembly that causes the pedal to physically stick, which can happen even with old-fashioned designs that still use a cable connected to the engine.The electronic aspect of the circuit is very safe, and having studied it, I had no hesitation about buying a car with such a design. In fact, as I wrote this post and thought about it some more, I have to conclude that the electronic system is far safer than the old mechanical systems.
Examples of the redundancy: There isn't one sensor connected to the pedal, there are actually two (or even three). The computer watches all of the signals and expects that they will agree with one another. Typically the computer also watches the brake light circuit and considers its status as another factor. If the brake lights are off and the accelerator pedal sensors agree that you're flooring it, the computer will let the engine go whole-hog. But it will probably only allow gentle acceleration if the brake lights are on (some drivers do habitually to drag their left foot on the brake pedal) or if there is some disagreement between the accelerator pedal sensors. If there is too much doubt with what is going on with those signals, the computer will only let the engine idle. On the same note, at the point where the computer controls the physical throttle at the engine, there is a feedback sensor that measures to see that the physical movement commanded is what is really happening. If this signal doesn't agree with what is expected, the car will only idle. And if the engine starts to run away from what the computer intends, and commanding the throttle to close doesn't work, the computer can start cutting back the fuel and spark supply through completely separate mechanisms to be sure.
sparkplug8 says:
08:13 PM, 01/28/2010
If I read this right, and maybe I don't, it would seem that the accelerator pedal just activates an electrical sensor, and is not mechanically connected to the engine.
If so, it seems to me that the problem could occur anytime something goes wrong with that electrical circuit, such as a shorted wire, a blown fuse, or a malfunctioning sensor.
Add to that the possibility that the responding servo on the engine's air/fuel system has a malfunctioning sensor or any kind of loose connection in the wiring, and you have a formula for disaster at any moment.
I understand that this type of throttle control is appearing on many vehicles. I hope I never will be driving one, with all those possibilities for failure!
colorado1974 says:
01:20 PM, 01/28/2010
Um, not sure where to go with that one. Does it matter? Let me say this again, very simply this time. Toyota designs the parts for all of it's cars and trucks. It then puts them out to suppliers to bid. The lowest bidder wins the contract and starts producing them. With the brands I represent, there might be 3 different window regulators based on production date, model year or assembly location.
Why doesn't matter now does it? Quit shirking the blame on American workers. Toyota designed the part and approved it for production. Enough said.
pbrahma says:
12:06 PM, 01/28/2010
colorado1974 - How come Toyota vehicles which equipped with DENSO pedal are not being recalled then? I guess Toyota should end their relationship between the CTS and leave obama scratching his head since Americans will be losing their jobs. Giving DENSO more production=more jobs for the Japaneses.
fire25 says:
10:00 AM, 01/28/2010
just another reason not buy a toyota
bryan1280 says:
08:20 AM, 01/28/2010
I think that colorado1974 has a good point, no company should ever try to "hide" something like this. Look at what happened with the Pinto. However, in a world that is sue happy, it is not in Toyota's best effort to admit anything. People will be suing anyway, Toyota does not need to put their head in the guillotine anyway. As far as the CTS buiding the assembly to Toyota specs, that can't be accurate as Denso is working off the same specs and is not malfunctioning.
leftoflane says:
08:08 AM, 01/28/2010
Great article. It pinpoints the problem very specifically. It's a sad state of affairs when we have to search out vehicles with VIN's that start with a "J", as I've made myself do for a few years now. It's not enough to simply buy a Toyota.
But there is hope for disillusioned Amercian car lovers like myself... Cadillac's latest offerings going back a couple years are encouraging not only in looks and interior quality, but reliability (and Ford's too without making this post too long). I'm making it a point to put a CTS Sport Wagon at the top of my short list when I can afford to relegate my FJ Cruiser to off road/weekend-only duty. For now all I can say is - glad I got a Denso.
guy1974 says:
07:34 AM, 01/28/2010
goonabike - made in Japan is irrelavant. It is what part and supplier they used.
Colorado has a good post. If Toyota are asking their dealers to hide how many accidents and deaths there have been then they should be ashamed. So should anyone who is a Toyota fanboy and sees nothing bad that they do.