Mitsubishi Montero Sudden Acceleration Accidents [MERGED]

[markshoti]

Thats exactly what sir Niky said. The brake override cuts power to the engine. Read his post again. However, the point is that even if there is failure of the brake override or in cars without brake override, the brakes is still stronger than the engine and stopping a car is no problem.

Posible ba na tumigas yung brake kaya di sila makapag brake? Minsan db bago mag start ng kotse minsan matigas ang brake hindi ma depress?

[niky]

Read the articles I provided and come back and comment after. The brake override is exactly not for the brakes but to cut power to the engine. That's why it said if the program locks up with the throttle at open, the brake override will not work to cut power off, that would result in sudden unintended acceleration.

Error handling is very important in any software and even so in critical embedded system (systems that could cause injury or death if they fail). A vehicle's ECU or ECM is a critical embedded system and has no room for error.

SUA and lack of brake override are two separate failures. Granted, caused by the same bit flip, if Barr is correct... but it isn't the death of the over-ride that causes SUA, it's the malfunction of the throttle controller that will do it. Even without the over-ride, the brakes should be functional... but not for very long on a gasoline car like the Camry, which requires engine-provided vacuum for brake boost. (The Montero has a separate vacuum pump, so the brakes should, theoretically still work)

If such errors can be proven on the Montero ECU, then that could answer some of the cases on the highway, but for some of the parking lot cases we've seen, the lack of brake lights still suggests pedal misapplication. (The cases here had eyewitnesses claiming that the brake lights were on and the brakes were being pumped, but the cars were not slowing down).

[vvti2.0]

Bakit kaya di magtest ang Mitsubishi ng remoted na montero, sabay apak sa brake at accelerator na walang override to prove their point na kung sa brakes umapak di lilipad ang sasakyan. Anyways, di ko lang maimagine kung ano yung ramp na inakyatan nung montero para umibabaw sa altis.

[spotdog11]

Posible ba na tumigas yung brake kaya di sila makapag brake? Minsan db bago mag start ng kotse minsan matigas ang brake hindi ma depress?

Before we start the engine, the brake pedal seem hard to depress since there is still not enough hydraulic pressure. It should feel normal once the engine is started. In sua, however, the engine is running so that is not an issue.

[lacson]

Thats exactly what sir Niky said. The brake override cuts power to the engine. Read his post again. However, the point is that even if there is failure of the brake override or in cars without brake override, the brake is still stronger than the engine and stopping a car is no problem.

Not if the throttle is already at full open and once it gets going it will be very hard to stop that because it's sudden acceleration and it's not expected by the driver.

Read the link I provided, it goes in detail on how they found the issue. It includes a test car on a dynamometer. Seven engineers reversed engineered the software, took them months on top of the NASA engineers' work to find the issue. They found the software was badly designed and badly written, it was in spaghetti code, the result of upgrades from the previous code. They had 10,000 global variables, imagine, you should not even have any global variables in your code, it's bad design.

[spotdog11]

Not if the throttle is already at full open and once it gets going it will be very hard to stop that because it's sudden acceleration and it's not expected by the driver.

Read the link I provided, it goes in detail on how they found the issue. It includes a test car on a dynamometer. Seven engineers reversed engineered the software, took them months on top of the NASA engineers' work to find the issue. They found the software was badly designed and badly written, it was in spaghetti code, the result of upgrades from the previous code. They had 10,000 global variables, imagine, you should not even have any global variables in your code, it's bad design.

Your links only points to the possible electronic issues which would cause throttle to go wild. A stuck throttle is not a big deal in old cars that use accelerator cable and I have personally experienced that several times on old cars. It is a fact sir that in any car, even a sportscar, the brakes is a lot stronger than the engine. Check out this video to see what I mean. https://www.youtube.com/watch?v=NOMYjiCiTYg

[niky]

Not if the throttle is already at full open and once it gets going it will be very hard to stop that because it's sudden acceleration and it's not expected by the driver.

Read the link I provided, it goes in detail on how they found the issue. It includes a test car on a dynamometer. Seven engineers reversed engineered the software, took them months on top of the NASA engineers' work to find the issue. They found the software was badly designed and badly written, it was in spaghetti code, the result of upgrades from the previous code. They had 10,000 global variables, imagine, you should not even have any global variables in your code, it's bad design.

I am not disagreeing with you in regards to the Barr testimony, let's be clear. I like the fact that he found a single point of failure, rather than previous studies which had to come up with very convoluted failure modes (which were very unlikely)

What I am saying is this: The brakes will still function. What is happening is that at the beginning of SUA, since the over-ride function and the throttle controller have a common failure point, according to the study, the brake over-ride doesn't work. We agree on this. But on the initial brake application, the brakes themselves should work. If the driver does not sufficiently slow the vehicle down, or does not exert full braking, the brakes will run out of vacuum on a gasoline powered car whose throttle is stuck open. This is why, in the runaway SUA cases on the hgihway that were being investigated here, repeated braking did not slow the car down.

On a diesel car, the brakes *should* still work because turbodiesels have no intake vacuum. They use a separate vacuum pump to power the brakes. So for the highway SUA incidents with the Montero, you still need two failure points, as opposed to one on a gasoline car.

I do agree that it will be difficult to stop the car if the driver isn't expecting it... most drivers don't press the brakes hard enough, and riding them to combat SUA can cause the fluid to boil or the pads to overheat, rendering the brakes useless.

I still wonder, in these cases, why the driver could not shift into N, as that is on a separate control module. I recall in one of the more famous SUA cases I've read about (a very old one), the throttle got stuck open due to a faulty cruise control, and the mechanical linkage of the cruise to the shifter prevented the driver from shifting into Neutral.

[glenn manikis]

I am not disagreeing with you in regards to the Barr testimony, let's be clear. I like the fact that he found a single point of failure, rather than previous studies which had to come up with very convoluted failure modes (which were very unlikely)

What I am saying is this: The brakes will still function. What is happening is that at the beginning of SUA, since the over-ride function and the throttle controller have a common failure point, according to the study, the brake over-ride doesn't work. We agree on this. But on the initial brake application, the brakes themselves should work. If the driver does not sufficiently slow the vehicle down, or does not exert full braking, the brakes will run out of vacuum on a gasoline powered car whose throttle is stuck open. This is why, in the runaway SUA cases on the hgihway that were being investigated here, repeated braking did not slow the car down.

On a diesel car, the brakes *should* still work because turbodiesels have no intake vacuum. They use a separate vacuum pump to power the brakes. So for the highway SUA incidents with the Montero, you still need two failure points, as opposed to one on a gasoline car.

I do agree that it will be difficult to stop the car if the driver isn't expecting it... most drivers don't press the brakes hard enough, and riding them to combat SUA can cause the fluid to boil or the pads to overheat, rendering the brakes useless.

I still wonder, in these cases, why the driver could not shift into N, as that is on a separate control module. I recall in one of the more famous SUA cases I've read about (a very old one), the throttle got stuck open due to a faulty cruise control, and the mechanical linkage of the cruise to the shifter prevented the driver from shifting into Neutral.

I think SUA victims, was 2-2.5 secs. late in braking... it is also possible that the sudden surge of power, cause them to panic, checking what the hell is wrong....thus braking late... while the car forward momentum is already in motion, and braking will now take a few meters to stop to a halt...

[minicarph]

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[Monseratto]

Dear Montero Sport Customer,

We are writing you to keep you updated on the issue of sudden unintended acceleration (SUA) claims. Currently, the Department of Trade and Industry is looking into this, and is expected to release its report shortly.

MMPC has been fully cooperating with the DTI panel. Our team attended the public hearing on December 2, followed by several technical discussions. Last December 4, we also invited the DTI panel and the media to simulate an SUA situation. We proved that it could be controlled because the brake has been designed to overpower the gas pedal even if it were at full throttle.

In all these venues, we stand by our technical findings that we found: THERE IS NO DESIGN, MECHANICAL NOR ELECTRONIC DEFECT IN ANY OF THE MONTERO SPORT units allegedly involved in SUA.

The complainants, however, remain unconvinced. It was for this reason that we are reiterating our position that a credible and competent third party be commissioned to help settle this issue. We have already presented our technical findings in various forums, and are open to all other independent and credible forums to show our commitment to producing only safe and quality vehicles.

In light of the recent media attention, we are explaining the facts again and again in the presence of the DTI investigating panel. We are making public all our findings to reassure our customers that the Montero Sport is completely safe and reliable, and has no SUA issues.

Please bear with us for now as we do our part to help resolve this issue. We also thank you for your continuing trust and patronage.

http://www.topgear.com.ph/news/indus...port-customers