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Tesla’s software update that resulted in battery capacity loss is under probe by NHTSA

The NHTSA is looking into a complaint by Tesla owners regarding a software update that resulted in battery capacity loss earlier this year.

They claim that it is related to a potential risk of fire.

Earlier this year, we reported on several reports from Tesla owners about seeing significant drops in range from 12 to 30 miles over a short period of time.

Only Model S and Model X vehicles with 85 kWh battery packs, which were discontinued in 2016, seem to be affected at this point.

For most owners, the range drop happened after updating to Tesla’s 2019.16.1 and .2 software updates.

Tesla owner David Rasmussen got one of the most severe drops we have seen so far.

At the time, he told Electrek:

“My 2014 Model S 85 was getting Rated Range of 247 miles until May 13. Now after the next update, it continued to drop to now 217 miles. This is an 11% drop in 5 weeks.”

Rasmussen has been plotting the battery capacity degradation of his Model S over the last 100,000 miles or so and the recent drop is quite obvious:

On top of the range loss, the DC fast-charging rate at Supercharger stations has also been reduced.

He went to his local Tesla service center with the issue and like most other owners reporting the same issue, he was told that is “normal degradation” of the battery pack.

After our report, Tesla said that the goal of the update is to “protect the battery and improve battery longevity” and it resulted in a range loss for only “a small percentage of owners.”

The automaker said that it was working on a solution, but nothing has changed months later and Rasmussen ended up filing a class-action lawsuit against Tesla.

The complaint was both about the sustained range loss and the fact that Tesla isn’t being clear about why they needed to “protect” the battery pack.

He believes that it was due to a series of battery fires.

After he filed the complaint, Tesla told us that they started releasing a software update to help with the range loss and stopped referring to a need to “protect” the pack.

Now he has also placed a complaint with the NHTSA’s Office of Defects Investigation (ODI):

“On September 19, 2019, the Office of Defects Investigation (ODI) received a defect petition dated September 17, 2019, requesting that NHTSA initiate a defect investigation of certain Tesla Model S and Model X vehicles that received revised battery management software in one or more over-the-air (OTA) updates from Tesla, beginning in May 2019. The Petitioner alleges that the software updates were in response to a potential defect that could result in non-crash fires in the affected battery packs and that Tesla should have notified NHTSA of the existence of this potential defect and conducted a safety recall. The petitioner also alleges that this software update reduces the driving range of the affected vehicles. A copy of the petition will be added to the public file for this defect petition and ODI will evaluate the petitioner’s allegations to determine if the petition should be granted or denied.”

The NHTSA is investigating the issue to see if the defect would require a recall investigation.

We contacted Tesla for a comment on the situation and we will update if we get a response.

Electrek’s Take

Like I said last time we reported on this issue when the lawsuit was filed, Tesla could have likely avoided this whole situation with better communication with the affected owners.

Tesla should have been clear about the reason for the update in the first place and what they are doing to give the range back to those people.

But the communication about this issue has been poor so far and now some owners are clearly frustrated enough to start legal action and petition NHTSA to probe the issue.

Now it raises the question: was the communication about this issue bad just due to normal incompetence on that front or is Tesla actually trying to hide a deeper issue about a defect of the affected packs?

Normally, I always go for stupidity over malice, but I have to say that there are a few weird things about this case, like Tesla first talking about the update “protecting” the battery pack.

We have been covering this situation for a while now and while I often say that Tesla is unfairly targeted by govt regulators more than other automakers, I think this issue is actually worth looking into.

I’d like to hear more from the affected owners.

What do you think? Let us know in the comment section below.

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