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GM Ignition Switch Defect Culpability 3

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Anil Ghimire

Mechanical
May 18, 2019
1
Who is to blame for loss of life because of GM Ignition Switch Defect: Engineers or the company?
 
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and what was the "fix",

A new key with a small hole in the center for the ring.

I have yet gotten the new key for my 2004 Monte Carlo and Silverado, but continue to get the notices.
Both of them also have complete dash stepper motor failures that was not even covered by warrenty
[mad]
 
Consumers,

Who wanted keyless entry transmitters integrated with the keys, which lead to larger keys, larger slots, and an undefined large offset-load because of that slot. It waan't the switch group that f'd this up. It was the keyless entry group. But the keyless entry group escaped blame.
 
"...wasn't the switch group..."

Readily available information is contrary to that. Apparently the switch itself failed to meet the stated minimum torque requirement.

Acknowledge in advance that the bigger picture would undoubtedly indicate multiple contributing factors, as always.

 
As more auto makers move to keyless ignition, this issue will be moot, or at least no longer relevant.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
Keep in mind that the Toyota runaway crash was the result of a keyless ignition switch, as is a new crop of car theft vectors with their attendant risks of killing people while evading police.
 
Keyless pushbutton ignition replaces this problem with other problems - notably that the means by which the engine can be switched off in a panic-emergency (see above-mentioned Toyota runaway incident) by a driver who hasn't read and memorised the 700 page instruction manual isn't the same as in the cars (with keyed ignition) that the driver probably took driving instruction in and has potentially been driving for decades. With a normal keyed switch, you switch it off. With a pushbutton, what do you do?

A momentary prod at the on/off button? If you, as the auto manufacturer, accept a momentary prod at the on/off button as an instruction to turn the engine and entire powertrain off while driving, what happens when someone accidentally prods the button momentarily?

Hold it down for 3 seconds? A lot of them are like that. If the driver is in a panic and wants to turn the engine off, 3 seconds is an awful long time when the car is accelerating towards the back of a transport truck in front of you.

A very small number of manufacturers have gotten what I think is the right approach. Keyless, but not a pushbutton. A rotary switch in the same place where every other car has its keyed ignition rotary switch, and with the same switch positions. Want to turn the engine off? Same action as in every other car.

Both late model vehicles in my driveway have a plain ordinary keyed ignition switch, and I am fine with that.

The other problem that GM ran into is one that is unrelated to the type of ignition switch. What do you do with the car's safety-related systems (including, nowadays, electric power steering, ABS, and the airbag system) when the driver switches the ignition off (by whatever means, whether deliberate or accidental)? In the old days, that ignition switch simply cut power to (almost) everything. No more engine, but now, no more ABS, electric power steering, or airbags. Now one needs to switch off the engine immediately, but keep the safety-related systems running as long as the vehicle has non-zero indications from its wheel speed sensors, and *then* turn them off.

The GM cars that were affected by this had a traditional ignition switch that cut power to everything (except possibly headlights) - which has been the way it was since the beginning of having ignition switches. The consequence that evidently nobody had thought through at the time, is that accidentally bumping the ignition switch off while driving, disabled the engine, which disabled power steering, which made the car hard to steer (not impossible, but hard enough that someone not expecting it, and someone not used to applying serious muscle to the steering, would be caught off guard), which led to the car leaving the road and hitting solid objects with the airbags disabled because the ignition was off.

The law of unintended consequences, is inescapable.
 
AFAIK the majority of the fatalities were because the key switched off as the car was leaving the road and before it hit an obstacle. The key switch didn't cause the accident; it just turned off the airbag which might have prevented a fatality. I doubt there were many cases where the crash was completely avoidable and the vehicle being driven in a suitably careful manner before the crash. I know - an infinite amount of money is worth it to save even one life - but no one acts like that is true outside a settlement negotiation.
 
Quoting 3DD: "...I know - an infinite amount of money is worth it to save even one life..."
This is of course not true, and 99% of all people do not live their lives this way. Engineers certainly do not.
The "even if it saves one life" comment is not a thoughtful one, however sincere. Engineers should never say that, unless they are speaking in a Senate hearing.
If you do indeed believe that line about infinite spending being justified, then lobby to lower the freeway speed limit to 30 miles per hour and require all vehicle passengers to wear safety helmets - this is guaranteed to save thousands of lives every year, just in the US. You don't want to do that? Does that mean you don't care about human life? Of course not.
We have laws and codes and the tort system that are progressively refined - beyond that, you cannot engineer 100% safety without going bankrupt in a week.
 
"no one acts like that is true outside a settlement negotiation."

Is there a defect in the forum that cuts off parts of sentences?
 
3DD
I think you and I agree - I should have made note of that, and given you the credit. I was placing an emphasis on what you already stated briefly.
This is a important concept that underlines many of the failure threads (i.e. if only we designed for a little more capacity, this failure would not have happened).
No defect in the forum.
 
There was a ton of speculation locally around Detroit about one or more of the engineers responsible for the switch being charged with everything from hampering the investigation to manslaughter. I believe when everything was said & done, GM simply paid a big fine and warrantied every possible switch and other failure. My wife's 2010 sat at the dealer three weeks due to lack of new switches and we were loaned a new Silverado with free fuel the entire time. I don't recall details but there were six other recalls on that car, every one of them insignificant to the point of seeming silly yet for every one we got a loaner vehicle and free fuel until the issue was fixed.
 
CWB1 - " we were loaned a new Silverado with free fuel the entire time"
I wish I had a brother who owned a dealership - - -
 
BrianPetersen forgot to mention that the power brakes were also disabled if that pretty key turned off the ignition.
What bothers me personally most is the fact, that some people at GM knew about the problem and did not initiate the fix immediately. They knowingly played with the safety of countless people - me and my family including.
In my case - as soon as the ignition switch in my car was replaced, I drove it to another dealership and traded it for a non-GM vehicle.
 
Vance, no relations at any dealerships, tho I did explore the possibility of buying a GM dealership last year. I had the necessary funding but GM wouldn't approve the sale as I personally have no direct dealership managerial experience. As to the warranty coverage, I think GM basically gave up arguing with the govt.

Stateside we need to reevaluate our driver licensing as the fundamental knowledge and driving skill has dropped significantly over recent decades while vehicle performance continues to increase. JMO but if somebody needs power assisted steering or brakes to safely handle a small, modern, disc brake equipped sedan then they shouldn't be driving period. Heaven help them when a brake line pops or they have other mechanical failure.
 
Most drivers accustomed to the normal level of power assistance would not be prepared for the enormous (>10x) increase in steering and brake pedal force to achieve the same effect.

Cars nowadays aren't designed with consideration towards minimising control forces when the power assistance is not working. This was different in the old days.
 
Star for Brian, and decades of driving for both of us and our two kids.

We've had a car equipped with push-to-start since the end of February, our first equipped this way. I have looked at probably more of the owner manual than most, and I haven't seen anything about stopping the engine while moving.

In our situation anyway, the car is also equipped with a conventional manual transmission and pedal-operated clutch. So worst case it'd be hold the clutch pedal down and let the engine bounce off the rev limiter. Once stopped, put it in one of the upper gears and stall it out.


Norm
 
A couple of thoughts on power brakes and power steering:
Power brakes were traditionally 'powered' by engine manifold vacuum, with a reservoir and check valve to maintain boost for a stop or two with engine off. (yes, the boost unit is effectively its own reservoir)
Some vehicles use a boost unit powered by the power steering hydraulic circuit. No idea if there's a reservoir for that.
But- if the vehicle is moving under power and the engine is cut off, classically it would windmill, being driven through the transmission - even if the trans is an automatic.
But - not sure how that works with modern automatics - lots of computer control, I wonder if the trans even keeps friction elements engaged when power is cut.
Hmmm.
So, in an older vehicle the engine would still be driven by the powertrain and you'd have power steering and power brakes.
Now, maybe you don't.
Plus, the 'no airbags' situation.
double-hmmm.


Jay Maechtlen
 
I believe modern brakes still use engine vacuum to boost pressure, although I'm sure there's infinitely more electronic bits between the master cylinder and caliper.

Most steering these days is electronic, so engine failure shouldn't have an effect unless your battery dies.
 
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