Valdemar wrote:Oh boy, this thread has definitely beaten all records by the amount of speculation contained. Just to throw one more into the mix, does anyone think that all these issues may be related to a bad batch of batteries?
Actually this hypothesis is probably the one that has the most legs.
Consider that it appears that all of these suspect cars are pretty much from the first major large scale delivery in 2011, with many of them coming in the May 2011 delivery batch. and that they are all being operated in extreme heat area in the south and southwest. It is possible that an early production batch of batteries may have a characteristic that would cause them not to operate to design when in a severe environment with some other unclassified (as yet) variable. Of the cars that are being examined, the battery component modules will be examined for their build dates and revision level, and that will be compared with the manufacturing information and board level component information to get a better understanding of what is going on and with the goal of finding a common issue.
The perfect scenario is that a specific component is found that in certain environmental and operational situations causes the issue. And that that particular component was superseded in later component releases. Then it is a simple (relatively) effort to find the cars that have this suspect component, and issue a TSB for those VINs to have it replaced with the newer component. This happens all the time with production runs of parts that are later discovered to have a defect.
But the second part of this puzzle is that it is really not known empirically how these suspect cars were operated. That does not mean that the drivers of these cars were operating them in an improper way, but it just means that it really isn't reliably understood how the cars were being operated because it has not been formally and scientifically investigated.
Now I know that several of you would dispute that, but honestly there really hasn't been any quality forensic evidence collected other than the anecdotal or interpretative data that has been seen here. Yes, there is 185+ pages of rants and raves mixed with some numbers, but none of the data I have seen here would stand up to scientific scrutiny. It may indicate symptoms, but it is not actionable data. Nissan has acknowledged that this data bears further investigation and is now doing just that.
The part of the investigation that Nissan will do with the customer cars and the drivers of these cars is important for them so they can have a better understand driving patterns in climates like Arizona. If Nissan can improve their modeling of how an EV vehicle is operated in harsh environments, then they can design and build a better car.