Budget Battery Capacity Readout

So my kneejerk decision almost 3 years ago seems to be paying off (with a little help from a lot of data)

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Honda just approved my full battery replacement under warranty at 86,000 miles at 38.8ah.

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@Thomas Clauser,

Nice to hear from you. I look forward to hearing details about your battery replacement process. Also, it will be interesting to discover if they provide a "new" battery, or is it refurbished in some way. I'm sure you will monitor the capacity once you get the replacement and we can see how 'new' it appears to be.

38.8 ah seems slightly above the warranty threshold. Did Honda readily agree or was there some arm-twisting involved?

Finally - What kind of time frame were you given for them to obtain the battery and do the repair?
 
Me too. I'm down to about 30 miles of range per charge. I think I'll be joining you in the not too distant future.
 
For mine, the vehicle threw a Power Systems Failure code at 38.8Ah. It is below the stated warranty threshold. I suspect that there are multiple things that can cause the code to be thrown near the end of the battery life. For mine, there were 3 or 4 cell strings that tended to drop if voltage faster than others. When the vehicle threw the code, I took it immediately to the dealer. After a few hours in the waiting room at the dealer they told me I should not drive the vehicle. They ordered a new battery and gave me a loaner to use for about 2 weeks. I had the vehicle back the day after the battery came in.
 
I broke 150k miles this month. I checked the battery capacity using a Honda HDS. The "battery pack capacity" is currently at 43.6 AH. I think that sounds about right for 150k miles.
 
My Clarity is 80K miles now, with 44.3 ah reading. We're just beginning 2025, so I figure I have about 4 years to get to warranty zone (or not). 2025 this year, 2026, 2027, 2028 until purchase date? -- I purchased September 2018. My rate of loss is 1.5 ah per year which has been very consistent since I first got the car. i.e. not more toward the beginning or later in the ownership, almost exactly 1.5 per year without fail. Anyway, prediction hold, I will not get to 36.6 but I may well get to 38.8. atlgwinnett- when you say the car threw a code, did you see something on the display?, or did you notice with an OBD-II checker (or both)?

Incidentally, the reason I ask is that I love this car. If I end up qualifying for replacement battery, I'll just keep driving it as long as possible.
 
As part of my service today for the fuel pump they are reading the battery capacity. I gave them the information on how to read it from this forum. They still seemed unsure of what it would take. It is very cold here in Illinois today and they wondered if outside temperature impacted the reading. I told them from all I understood it did not, and it was just a reading the vehicle maintained.

Did I instruct them correctly?
 
jray19 said:
As part of my service today for the fuel pump they are reading the battery capacity. I gave them the information on how to read it from this forum. They still seemed unsure of what it would take. It is very cold here in Illinois today and they wondered if outside temperature impacted the reading. I told them from all I understood it did not, and it was just a reading the vehicle maintained.

Did I instruct them correctly?
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I think so. We have battery capacity readings from a number of Clarity's from all times of year and temperature. If temperature changes cause different readings we would see fluctations in the data and we don't see it.
 
Sorry for the delay in response, folks. Honestly, I've been trying not to jinx this. At present my replacement battery shipment is still showing as 'on hold' with no date expected for shipment. But the dealer assures me that everything warranty-wise is submitted.

Here's the quick and dirty version. 2 weeks ago I started my car and every light came on but the car would not start. Assuming a dead 12v battery, I jumped it and it fired right up. After about 5 miles of driving I got a check engine light and an error stating that I could not change the "drive mode". Upon arrival I have OBDII errors codes of P1DC7 and P0A7F (hybrid battery pack deterioration).

I brought the car to the dealer with no agenda. Just with the note that the check engine light was on and the circumstances leading up to it.

After about 48 hours it was clear that they were struggling to diagnose the vehicle. That's when I provided them with the PDI, the warranty parts list, and my current battery capacity (38.8) compared to the warranty threshold. 24 hours after that they said that they said that all this points to the battery needing replacement and they started down that path.

So that's where I sit.

From my experience so far, here is what I'd recommend:
1) A check engine light or error code is what will start the ball rolling (without that, capacity alone won't get you anywhere. There's nothing for them to diagnose)
2) Let them do their jobs before thrusting your expertise on them. They're typically good at what they do, but most people haven't even heard of a clarity much less worked on one
3) Offer them the information you have and offer your opinion about what it could be. My thought is after 2 days of struggling with a car they knew little about, they were about to make a hail mary decision anyways. This at least gives them the information to make an educated decision

Stay tuned! At this point I envision someone with a flashlight looking for the crate market "Clarity Traction Battery" in the warehouse from the last scene of Raiders of the Lost Ark.
 
My 2018 Base Clarity is at 93,787 miles with a battery capacity reading, using my ELM reader, of 37.14. According to this forum, it seems that the warranty replacement limit is 36.6. Even in mild weather here in Phoenix, I normally only get about 32 miles of EV range. I've only ever charged with the OEM L1 charger, but charge almost every night.

It's going to be an interesting race to see if my battery drops below the 36.6 threshold level before 100,000 miles. Is the ELM reading likely to be any different than the reading that a dealer would read (assuming that I can get a dealer to check the battery capacity for me)?

Any suggestions from those who have more experience with what dealers are likely to do for me?
 
Miles777 said:
Any suggestions from those who have more experience with what dealers are likely to do for me?
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Wow, you are very close... It's too bad you don't live in a "California Emissions State" where you would be covered for 150K miles.
As far as we know, the value that you read with the ELM device is exactly the same as what the dealer would read.

We really have not heard of very many battery failures here. A couple of posts back, @Thomas Clauser had gotten agreement in principal to have his battery replaced with a value that was slightly above the published threshold. His reading was 38.8, but as of his most recent posting, his dealer had not produced a new battery and I think he had to press the issue before he got 'agreement'. It will be interesting to see how his scenario progresses.

Bottom line - I don't think there are very many who have experiences with warranty replacement... At least, not that we have heard about here.
 
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MrFixit said:
Wow, you are very close... It's too bad you don't live in a "California Emissions State" where you would be covered for 150K miles.
As far as we know, the value that you read with the ELM device is exactly the same as what the dealer would read.

We really have not heard of very many battery failures here. A couple of posts back, @Thomas Clauser had gotten agreement in principal to have his battery replaced with a value that was slightly above the published threshold. His reading was 38.8, but as of his most recent posting, his dealer had not produced a new battery and I think he had to press the issue before he got 'agreement'. It will be interesting to see how his scenario progresses.

Bottom line - I don't think there are very many who have experiences with warranty replacement... At least, not that we have heard about here.
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Here's a chart of the decline in my battery capacity vs. mileage up to my most recent reading at 93,787 miles. For reference, I inserted the 36.6 warranty value at 100K miles to see how that data point would fit the trend. If the capacity keeps declining as it has recently, I may just qualify for a warranty replacement after all.

It does seem to both my wife and myself that the ICE turns on more readily now even when there is EV range remaining, as if the threshold for using the ICE power during acceleration is lower than it used to be.
 

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Miles777 said:
Here's a chart of the decline in my battery capacity vs. mileage up to my most recent reading at 93,787 miles. For reference, I inserted the 36.6 warranty value at 100K miles to see how that data point would fit the trend. If the capacity keeps declining as it has recently, I may just qualify for a warranty replacement after all.
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The number of miles between each capacity measurement varies quite a lot in your case. If the chart doesn't account for this, it can sometimes fool you when trying to interpret a trend... So, I re-plotted your data with a more accurate scale on the X-axis:

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Even plotted this way, it sure looks like you are headed toward a warranty situation. It will be close, but even if you don't quite make it, I think you have a very strong case and you should fight for it. The fact that you have this data which clearly shows the progression may be valuable if you find yourself in a dispute.
 
MrFixit said:
The number of miles between each capacity measurement varies quite a lot in your case. If the chart doesn't account for this, it can sometimes fool you when trying to interpret a trend... So, I re-plotted your data with a more accurate scale on the X-axis:

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Even plotted this way, it sure looks like you are headed toward a warranty situation. It will be close, but even if you don't quite make it, I think you have a very strong case and you should fight for it. The fact that you have this data which clearly shows the progression may be valuable if you find yourself in a dispute.
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Thank you for taking the time to replot the data. I'm amazed at how linear the battery capacity decline looks when plotted correctly.

I bought a 120,000 mile, 6-year Honda Care warranty for $1,659 when the car was "nearly new" (shortly before it reached 36,000 miles), but the contract doesn't specifically state that it covers a traction battery. If it does, that could tip the scales in my favor if my battery does not drop to the 36.6 warranty level before 100K miles.

I'm going to start reaching out to the two dealers that have done 100% of my Clarity maintenance work to gauge their level of interest in looking into this for me. I'll keep you all posted.
 
So, I just got back from talking with the service rep at Arrowhead Honda. He said that they've replaced at least one Clarity battery before. He recalled it being somewhere in the $8-9K range. He also said that there will be a fault code recorded when the battery capacity drops below the warranty level. I'd never heard that before.

He also said that my 6-yr 120K Honda Care warranty should apply to my car's battery, so it looks like there's a new battery in my future. A new/remanufactured battery would be a good outcome, as I really like the Clarity and wouldn't mind keeping it another 100K miles.
 

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