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battery moisture error

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I have photos and video I can share, and a story about my car's refusal to charge Friday evening due to a error that Tesla emergency tech support identified as "moisture in the battery pack". The next morning it started charging fine.

Update: The moisture error is continually showing up in my car's error logs, according to Tesla. Although I wouldn't know it because I'm not having any errors show up on the screen, nor have I had any more charging problems after the one that first night at the races in August.

Nevertheless, Tesla says the battery needs to come out. This is what Tesla just told me:

It is still necessary to have the battery removed and inspected to find out how the water is getting inside the ESS or if the sensor is not working correctly, however it does not need to return to CA for this work. We now have the ability to remove and install the battery in Boston at a technical college, Benjamin Franklin Institute of Technology, so we will replace your battery and send the old one back to California for disassembly and inspection.

I get a brand new battery!
 
No of course not.

I'm happy that was the case, but I'm somewhat surprised given how they are firming up their policies.

I had to pay for the mobile service to come out and do an in warranty repair (ESS fan started throwing errors). I could have paid to have it transported to the nearest store (120 miles) instead. I was given no other options (was told trying to drive it there could result in a no run).
 
How long you going to be without the car?
Was told 8 days. But I want them to have it over my Christmas vacation so it will be a few days longer than that I suspect.

I'm happy that was the case, but I'm somewhat surprised given how they are firming up their policies.

I had to pay for the mobile service to come out and do an in warranty repair (ESS fan started throwing errors).

Odd. I wonder what makes them charge and what makes them not. I hope it's not a regional thing.
 
It is great that Tesla is showing such great warranty support for the Tesla Roadster. Replacing an entire battery pack just because of a sensor error?

They don't know whether the sensor is bad or if there really is moisture getting in the supposedly sealed battery pack. They won't know until after they disassemble it. I imagine that's distinctly non trivial, and may need to be done in an environmentally controlled environment.

I agree with your sentiment. But it does make complete sense, for reasons that have nothing to do with customer support to one customer. Give the customer a new battery and send him on his way. Then they can use my old battery however they wish in order to diagnose. If there happens to be any kind of manufacturing defect that is found, they need to completely understand it.
 
I believe their policy on battery replacement is that they will repair a battery and then use that in another Roadster.

For example, if your battery is removed with 5,000 miles on it, then they repair the sensor issue or whatever other issue was the cause, that battery pack can be put into another Tesla Roadster that needs a replacement.

But it can only be used to replace a battery pack that has more miles.

So lets say another customer needs a battery replacement after 10,000 miles.
Your 5,000 mile battery pack that has been fixed is eligible to be used in a different customer Roadster that had 10,000 miles already.

So you might not get a brand new battery. But you will at least get one that had fewer miles on it when the replacement happens.

It makes sense to me. They cannot just dump these battery packs. They are too expensive. And most likely there is nothing wrong with the cells. It is some minor issue that can be repaired.

All of this knowledge of how batteries are holding up, under real world use, will help them design a better battery pack for the Model S.
 
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When replacing a battery pack in an EV the question arises, since the value of a battery pack will most likely diminish as it accumulates miles, how do you tell how many miles are on the battery pack? Does the Tesla battery pack keep an internal electronic odometer?

I guess it would make sense that when a battery pack is replaced the technician would indicate a replacement was installed at so many miles in the cars internal log. But would it also indicate how many miles were on that replacement pack before it was installed?

When an EV is sold, the buyer should be able to obtain the log for that car that would indicate all of it's history, but will that happen? Of course that would have to be provided by the current owner, I doubt Tesla would provide it to anyone but the registered owner.

When an engine is replaced in an ICE what is the standard practice to indicate the miles on the new engine? I can't imagine they reset the odometer. (never had to replace an engine)
 
When replacing a battery pack in an EV the question arises, since the value of a battery pack will most likely diminish as it accumulates miles, how do you tell how many miles are on the battery pack? Does the Tesla battery pack keep an internal electronic odometer?

I guess it would make sense that when a battery pack is replaced the technician would indicate a replacement was installed at so many miles in the cars internal log. But would it also indicate how many miles were on that replacement pack before it was installed?

That is easy enough to track. Just note the odometer miles when the battery goes in and out. They can easily track number of miles on a specific battery pack. I would be shocked if such basic info was not recorded.
 
No of course not.

At 2850 miles on #635 MY2010 Roadster, I went out one morning to a "Power Failure - Service Required" fault onscreen. The car will not charge or move for that matter, although it indicates 188 Ideal miles. Tesla suspects a high resistance wire causing a sensor to indicate an over voltage condition in the battery. Tesla trailered the car to Chicago (30 miles) for a new (different?) battery replacement.
It was indicated that I will be paying for the flatbed transportation.
 
My concern over a replacement battery would be how it's been used or abused; the number of range charges for example and if it's been really discharged. I think the computer keeps track of that though.

This also covers why the idea of a swapable pack wouldn't work for me; I've only done one range charge and don't plan on doing many more.
 
My concern over a replacement battery would be how it's been used or abused; the number of range charges for example and if it's been really discharged. I think the computer keeps track of that though.

This also covers why the idea of a swapable pack wouldn't work for me; I've only done one range charge and don't plan on doing many more.

This is also a concern of mine as I too am conservative with my battery. We could only hope the previous battery owner will be just as conscientious.
 
It goes deeper than that.

Battery sheets are replaced. The ones t be replaced are checked for charge level and the new ones are charged to exactly match before insertion.

A "battery" is a group of cells. Anyone of them could now be a bunch of different new cells or perhaps the good bits from other batteries.