12V Battery

This is an individual decision that you need to make based on the impact that a failed battery would have to you personally.

For me, I will just wait for it to die (or exhibit signs of imminent death) because I carry a jump starter pack. I am retired, and a dead battery would be a minor inconvenience. I would just purchase and install my own replacement battery when that time comes.

If being 'stranded' is a big worry for you. If you would need to be towed somewhere when the battery failed. If you are worried about 'danger' if your car doesn't start and you would not know how to carry / use a jump starter, then having it replaced preemptively would be perfectly sensible.

 

Co

connect a battery charger to the leads, so when you disconnect the battery, you will still have 12v to the car systems.

 

Well, this is a little tricky. In the old days, you could sense that a car didn't crank as vigorously (especially when cold) but the Clarity does not have a starter that operates on the 12V battery like a conventional vehicle. Perhaps after pondering this a little more, maybe I would say that sudden death is likely to occur without any warning signs.

All of the 'settings' that I can think of are non-volatile (meaning that they are retained even if the battery goes dead, or is replaced). We do have some suspicion that the HV battery capacity reading will get 'reset' if the 12V battery is dead or disconnected for a 'prolonged' period, but it will be re-calculated over time and only matters if the HV battery goes bad and there is the need to evaluate the warranty coverage.

 

While replacing AC condenser (again but covered under warranty extension) my technician noted 12 v battery failed stress test so I just had them replace it. Probably paid more than I should have but planning long trip and didn't want to mess with it
2019, 24,000 miles

 

Nothing really, I did that on my Father-in-law's car. Just had to deal with the warnings having to reset during the first drive afterward. Takes like 2 minutes from what I remember for all to reset...

 

Check the battery voltage if you have a voltmeter. It should be at least 12.5v. Replace the batt if it is below that.

 

It is probably better to do a load test. Any automotive parts store will do this for free while you wait.

 

Agreed. A stress test would be best.

 

Are you prepared to handle a situation where you arrive at the car and the 12V battery will not power up the system? If not, you may want to replace the battery before you find yourself in such a predicament.

The downside to this approach is that you may be replacing a battery that has years of life remaining and that cycle will be repeated with the next battery. Some owners carry a lithium jump pack for just such an occasion. The Clarity just needs a 12V power source to get the party started, so even the lowest cost option should do the trick. These devices can also be handy for charging phones and computers.

A few owners have also reported having a dead battery after leaving the car to sit for a few weeks. I had that happen after leaving it for 6 months, however, leaving it for 4-6 weeks did not drain the battery. I now use a Battery Tender whenever the car will not be operated for more than several weeks. Such a device might be something to consider if the vehicle will be left to sit for an extended period of time. Solar maintainers are also available in the absence of an AC power source.

 

I grew up in Oregon, and until I was maybe 20 years old I had never met someone who had air conditioning in their home. Maybe not these days with climate change, but growing up western Oregon and Portland was a very cool and damp place, and really even in the summer time. Can't count how many times our summer camping trip in mid July was rain ever day of it. Anyway, that being said, on a couple of occasions I've literally had 12v batteries last 17+ years. No not exaggerating, they have have the date on the battery. So if you don't mind risking being stranded AND you live in a very cool place, you can leave a battery way beyond the recommended limits. I've done it with more than one vehicle, and yup gas powered with cranking amps involved.

In fact, I was planning to basically never replace my Clarity battery because I just don't care if it quits. I have a lithium ion jump kit like others have mentioned. When my car had a weird problem at 40K miles, I did replace my battery. The problem ended up not being related to the 12v, but I didn't let it sit in there forever like I planned and have done most of my life. I basically never replace a battery until I'm stranded, and it just isn't a big deal to me.

And as others have mentioned, this gets personal fast. Some people really can't be stranded and think of it as a small adventure. For example, if I had young children in the car, that would be out the window.

Also, if not obvious, heat kills batteries. If you live in say Phoeniz AZ you likely need to replace within 4 years whether you want to or not. Batteries cannot deal with 120F. (and some humans, me included, can't either).

 

1. Press and hold down "Audio" + "Menu" + "Brightness" keys together at the same time until your diag menu appears on screen.
2. Enter the "Detail Information & Setting" screen
3. Enter the "Functional Setup" screen
4. Enter the "Save User's Memory" screen
5. Make sure you have a USB stick inserted into one of the USB slots (I usually use the #2 bus, which is the one on the passenger side); you may need to have it formatted to a compatible file format prior to use (FAT32 if I remember correctly).
6. Hit "Export"

You should be able to come back to the same menu and use "Import" to restore your data. DISCLAIMER: I've never personally used this function before, so I can't make any assurance exactly what gets backed up/restored and what doesn't.

Also note, if you have HondaHack installed and you have root, you should also be able to take a backup of the Android environment side via ADB. The HH settings has an option to enable wireless ADB, which I've tested myself before and it does function. Once again though, I've never used it to run ADB shell bu or restore before, so I can't guarantee what does or does not get backed up/restored. Futhermore, although I do have root on my HMU, I've never actually granted root to my shell session before (have not encountered the need to do so thus far), so I'm not certain this is easily doable or even viable.

 

The OEM battery has a little window with status of the battery, as long as it shows "OK" (blue outside and red dot on the inside) I wouldnt worry about it. Japanese batteries are beasts, I had one last 11 years before dying on a Lancer.

 

My OEM battery died in the first year, but it was due to the nature of my commute to work. Long story short, my battery would be habitually undercharged, and I did not have any practice of supplementing the 12V charging or conditioning the battery back then.

 

Did it actually fail or gradually got discharged due to short drives? Ive experienced in the past on an Accord where short drives (less than 10 miles each way) discharged the battery over course of about a year to the point where the car wouldnt start anymore. All I had to do is charge it up manually and it would last another year (but I got into habit of doing it every 6 months or so). One thing on Clarity and other Hondas that drains the battery fast is the automatic seat adjustment based on key fob if you have regular multiple driver usage. Every time you open the door the seat adjusts to that fob, seat adjustment motors draw a lot of power each time entirely off the 12V battery. So I turned off auto seat adjustment based on FOB and make it a point to start the car first before hitting the seat adjust button.

A decent trickle charger is about $20, but very simple one can be as low as $5. I have one of these and its been working great: https://www.harborfreight.com/automotive/battery-tools-accessories/battery-chargers-maintainers/4-amp-fully-automatic-microprocessor-controlled-battery-chargermaintainer-63350.html

This would work just fine for $10: https://www.harborfreight.com/automotive/battery-tools-accessories/battery-chargers-maintainers/12v-automatic-battery-maintainer-59000.html

 

Yes, that's exactly what happened to me as well. I ended up buying a 12V battery jump starter that also has several other functions built-in, including conditioning mode (which I believe is the "trickle charging" you're referring to?).

 

Yeah trickle charging is called conditioning by some. None of this is necessary on Clarity though, our commute didnt change, and when I connect trickle charger to Clarity's 12V battery after not doing it for years, it tops out within an hour (discharged battery will charge 12 to 24 hours). So Clarity keeps it topped up on its own.