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Unintended Acceleration - Find the Cause

2237 messages,  Last post on Feb 26, 2013 at 1:36 AM

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What is this discussion about? Toyota, Hyundai, Lexus, Ford, Audi, Automotive News, Legislation

Messages Page 223 of 224

#2218 of 2237 Re: Forget the Red Button [andres3] by wwest

Jan 11, 2012 (8:53 am)

Replying to: andres3 (Jan 10, 2012 11:12 am)
"..My AC failed, but it wasn't due to the computer..."
 
How would YOU know...?
 
And....which computer...?
 
The engine/transmission ECU that is supposed to disable the A/C clutch during WOT, or closely nearby, engine operation...?
 
Or was it the one (or 2) in the A/C control "head" that didn't fail...?

#2219 of 2237 Re: Forget the Red Button [wwest] by andres3

Jan 11, 2012 (9:48 am)

Replying to: wwest (Jan 11, 2012 8:53 am)
The engine/transmission ECU that is supposed to disable the A/C clutch during WOT, or closely nearby, engine operation...?
  
Or was it the one (or 2) in the A/C control "head" that didn't fail...?
 
if the A/C can't handle WOT without destroying itself, that sounds like a design and engineering issue, not a computer issue.

#2220 of 2237 Re: Forget the Red Button [andres3] by wwest

Jan 11, 2012 (10:16 am)

Replying to: andres3 (Jan 11, 2012 9:48 am)
No argument there, the design may not be robust enough for operating above ~4,000 RPM. But still, it wouldn't have failed had the ECU not left it enabled.

#2221 of 2237 Re: Forget the Red Button [wwest] by andres3

Jan 11, 2012 (10:46 am)

Replying to: wwest (Jan 11, 2012 10:16 am)
But still, it wouldn't have failed had the ECU not left it enabled.
 
But how would we ever know that, couldn't it have just been a poorly assembled compressor?
 
Wouldn't an ECU malfunction trigger a Check Engine light or some other warning light or readable error code.

#2222 of 2237 Re: Forget the Red Button [andres3] by wwest

Jan 11, 2012 (5:56 pm)

Replying to: andres3 (Jan 11, 2012 10:46 am)
"...couldn't it have been..."
 
Yes, but I was "rebuting" the statement that there was no computer "failure" associated with the compressor failure.
 
"...Would an ECU malfunction trigger..."
 
Possibly not, the A/C monitor firmware will provide an indication and throw a code if the compressor is enabled but NOT rotating cognizant with engine RPM. The inverse case is a "corner case" and would be mostly needless.

#2223 of 2237 Re: Forget the Red Button [wwest] by houdini1

Jan 12, 2012 (9:13 am)

Replying to: wwest (Jan 11, 2012 5:56 pm)
I'm with andres3, all of this is pure speculation...if not outright hogwash !!

#2224 of 2237 Re: Forget the Red Button [houdini1] by wwest

Jan 12, 2012 (11:14 am)

Replying to: houdini1 (Jan 12, 2012 9:13 am)
Speculation...Yes, YES.
 
That was the actual intention.
 
Hogwash !!
 
NOT.

#2225 of 2237 Re: Forget the Red Button [houdini1] by la4mead

Jan 12, 2012 (1:05 pm)

Replying to: houdini1 (Jan 12, 2012 9:13 am)
Yes, I agree. This discussion frequently takes turns away from the topic.

#2226 of 2237 A needed fix? by Stever@Edmunds HOST

Apr 12, 2012 (9:55 am)

"Federal regulators plan to require automakers to design a brake-throttle override system into future vehicles to reduce the risks of high-speed, unintended acceleration.
 
The proposal by the Department of Transportation’s National Highway Traffic Safety Administration is a result of a highly publicized 2009 crash of a Lexus ES 350 and a subsequent flood of complaints about incidents of unintended acceleration in Toyota and Lexus vehicles."
 
 Federal regulators want brake override systems in all cars (LA Times)

#2227 of 2237 Re: A needed fix? [steve_] by wwest

Apr 13, 2012 (10:00 am)

Replying to: Stever@Edmunds (Apr 12, 2012 9:55 am)
If they expect it to be functional then it will need to be implemented separately from the engine/transaxle control ECU.

Messages Page 223 of 224

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