Cash Traylor
Well-Known Member
**Skip to 3rd paragraph for the punch line without backstory.**
Greetings everyone, it has been a very long time since I have posted (live got busy). I still have my 2018 Clarity, it has been a great car and after all the mods I did I found it difficult to part with. I am rapidly approaching the end of the 8 year warranty this summer for the powertrain (only has 70K miles on it). Any who remember my other posts and those of Mr. Fixit and KentuckyKen know that the battery capacity and HV system was of great interest to me. Each year, for my annual oil change and state inspection I would have my capacity "officially" tested by the dealer and a record kept. Everyone now has access to this data via the OBD2 port now using "Car Scanner" or other software, but back in the day it was Schrodinger black box. My battery was declining predictably and was now at 37.8 Ah beginning of this year after losing 1.8 Ah in less than a year, likely due to a cell or two going high resistance finally. Anyway, I am close to the apex of battery going below the warranty threshold at the same time my warranty expires. Time to watch the numbers and prepare my oral arguments.
Took my vehicle in for it's annual service and it was due for coolant flushes, trans fluid, brakes and oil, basically all the liquids. The local Richardson Honda dealership was not really prepared tech wise to do this (they thought there were only two coolant loops). Finally received my car and drove it home, or I should say drove it 2.5 miles towards my home - then I got the power train overheat dash message, power reduced followed by 10 seconds later critical overheat and shutdown. From limp mode to shutdown in 5-10 seconds. Had to have the car towed back to the dealer. P0A3C DTC set. Seems the IPC was not flushed and bled correctly and it overheated due to trapped air. Had to leave it for the day and collect it a day later after reservicing the coolants and they took it for a 50 mile test drive to confirm work. Now, I have been lucky, 8 years and this was the first issue (first DTC seriously), but I take good care of the car and had planned to keep it out of warranty. So now a new issue, an overheat IPC history and warranty expiring. The dealer offered to cover the IPC for another 12 months in case there was undiscovered damage... ugh - ok. They also "cleared the DTC codes." Ok, this is the point of the post.
When I returned to pickup my functioning vehicle they gave me my new paperwork with a new HV capacity report. It now indicated 55 Ah capacity. They told me they had been measuring it incorrectly all these years. So, yeah - brand new battery... Well, actually this is akin to rolling the odometer back! I asked how this could have happened as that simply made no sense. To day the only way the BMS SOH could be reset was intentionally using the recalibration procedure when you actually replace the HV pack. The dealership called Honda America Engineering, which will not allow you to be in the room when that happens.
Now, since that date I have driven 500 miles and the HV Cap is now showing 50.8 Ah in 4 weeks since the "reset". I do believe that the BMS will eventually align with the SOH of the pack. However, this is taking far longer than I expected. At this rate it will likely not align prior to my warranty expiring. In the meantime I have a Clarity that does not know the size of its "angry pixie" fuel tank and behaves oddly. I know the EV range is always a WAG, but the SOC gauge is normally pretty close. Mine is now all over the place and the car can run completely dead on the highway before the ICE even starts (that is fun). I certainly have a drivability complaint but Honda has already taken the stance that the system will correct itself in short order.
The real punch line is that apparently there is no Honda Engineering method to evaluate an HV battery. Your warranty claim (outside of a complete battery failure) based on degraded capacity is solely based on the data stored in the adaptive memory BMS system. Data that should be protected by one of those multiple "are you sure you want to reset this DTC or Data".... "tech, are you really certain?" "Ok, we will reset this data if you press and hold your mouse button while holding the right and left shift keys and the function 10 key (yes, you may need another person to accomplish this) type warning message on their tech laptop. Instead, that data could be deleted and you have no way to prove your battery capacity for warranty. Convenient in my mind....
Recommend if you still own a Clarity that you get your capacities tested regularly at the dealer and have them initial them as being performed according to the "warranty test procedure" from Honda. I did that, but the reports were never validated against the "warranty" procedure that is required by Honda to fulfill warranty on the battery (some dance of warm the battery, charge the battery, cool the battery, then read the number etc). They can give you the readout and I thought that was good enough. Honda Engineering claims otherwise... and talked my dealership into discounting the historical numbers.
Just wanted to pass this on. With my battery numbers I admittedly would likely not have made warranty threshold. However, after the dealer data reset it is now a certainty....
Attached are the last two reports 9000 miles apart, showing my battery magically becoming new.
Cheers and best wishes to all,
Cash
P.S. I do have a formal complaint filed with American Honda Customer Care - I am not holding my breath.
Greetings everyone, it has been a very long time since I have posted (live got busy). I still have my 2018 Clarity, it has been a great car and after all the mods I did I found it difficult to part with. I am rapidly approaching the end of the 8 year warranty this summer for the powertrain (only has 70K miles on it). Any who remember my other posts and those of Mr. Fixit and KentuckyKen know that the battery capacity and HV system was of great interest to me. Each year, for my annual oil change and state inspection I would have my capacity "officially" tested by the dealer and a record kept. Everyone now has access to this data via the OBD2 port now using "Car Scanner" or other software, but back in the day it was Schrodinger black box. My battery was declining predictably and was now at 37.8 Ah beginning of this year after losing 1.8 Ah in less than a year, likely due to a cell or two going high resistance finally. Anyway, I am close to the apex of battery going below the warranty threshold at the same time my warranty expires. Time to watch the numbers and prepare my oral arguments.
Took my vehicle in for it's annual service and it was due for coolant flushes, trans fluid, brakes and oil, basically all the liquids. The local Richardson Honda dealership was not really prepared tech wise to do this (they thought there were only two coolant loops). Finally received my car and drove it home, or I should say drove it 2.5 miles towards my home - then I got the power train overheat dash message, power reduced followed by 10 seconds later critical overheat and shutdown. From limp mode to shutdown in 5-10 seconds. Had to have the car towed back to the dealer. P0A3C DTC set. Seems the IPC was not flushed and bled correctly and it overheated due to trapped air. Had to leave it for the day and collect it a day later after reservicing the coolants and they took it for a 50 mile test drive to confirm work. Now, I have been lucky, 8 years and this was the first issue (first DTC seriously), but I take good care of the car and had planned to keep it out of warranty. So now a new issue, an overheat IPC history and warranty expiring. The dealer offered to cover the IPC for another 12 months in case there was undiscovered damage... ugh - ok. They also "cleared the DTC codes." Ok, this is the point of the post.
When I returned to pickup my functioning vehicle they gave me my new paperwork with a new HV capacity report. It now indicated 55 Ah capacity. They told me they had been measuring it incorrectly all these years. So, yeah - brand new battery... Well, actually this is akin to rolling the odometer back! I asked how this could have happened as that simply made no sense. To day the only way the BMS SOH could be reset was intentionally using the recalibration procedure when you actually replace the HV pack. The dealership called Honda America Engineering, which will not allow you to be in the room when that happens.
- I asked the dealer to inquire of engineering about a "manual battery capacity test" method to confirm capacity against the warranty statement. No such process is possible on the Clarity.
- I asked them to confirm how the battery health data was reset without replacing the HV pack. Engineering declined to comment pending further evaluation (and me leaving the car with them for 3-5 days). I pointed out that a "software" reset, especially if it can happen "accidentally" during the dealership clearing stored DTC codes is problematic for warranty "trust."
Now, since that date I have driven 500 miles and the HV Cap is now showing 50.8 Ah in 4 weeks since the "reset". I do believe that the BMS will eventually align with the SOH of the pack. However, this is taking far longer than I expected. At this rate it will likely not align prior to my warranty expiring. In the meantime I have a Clarity that does not know the size of its "angry pixie" fuel tank and behaves oddly. I know the EV range is always a WAG, but the SOC gauge is normally pretty close. Mine is now all over the place and the car can run completely dead on the highway before the ICE even starts (that is fun). I certainly have a drivability complaint but Honda has already taken the stance that the system will correct itself in short order.
The real punch line is that apparently there is no Honda Engineering method to evaluate an HV battery. Your warranty claim (outside of a complete battery failure) based on degraded capacity is solely based on the data stored in the adaptive memory BMS system. Data that should be protected by one of those multiple "are you sure you want to reset this DTC or Data".... "tech, are you really certain?" "Ok, we will reset this data if you press and hold your mouse button while holding the right and left shift keys and the function 10 key (yes, you may need another person to accomplish this) type warning message on their tech laptop. Instead, that data could be deleted and you have no way to prove your battery capacity for warranty. Convenient in my mind....
Recommend if you still own a Clarity that you get your capacities tested regularly at the dealer and have them initial them as being performed according to the "warranty test procedure" from Honda. I did that, but the reports were never validated against the "warranty" procedure that is required by Honda to fulfill warranty on the battery (some dance of warm the battery, charge the battery, cool the battery, then read the number etc). They can give you the readout and I thought that was good enough. Honda Engineering claims otherwise... and talked my dealership into discounting the historical numbers.
Just wanted to pass this on. With my battery numbers I admittedly would likely not have made warranty threshold. However, after the dealer data reset it is now a certainty....
Attached are the last two reports 9000 miles apart, showing my battery magically becoming new.
Cheers and best wishes to all,
Cash
P.S. I do have a formal complaint filed with American Honda Customer Care - I am not holding my breath.
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