2013 won't start after low 12V battery event

This morning I went outside and found the car had quite a bit of dew on all the windows. I turned it on in accessory mode (two presses of the power button without a foot on the brake), set the heater on recirulate and 65°, and went back inside for about 9 minutes. When I came back the heat wasn't running and trying to start the car got a rapid cycling of the dash display between what looked like the shutdown screen and this:
IMG_1271 by wagen13, on Flickr
My wife looked up "T/M system malfunction" and found a thread here that said it might be due to a low 12 V battery. Sure enough, putting my voltmeter on the little battery showed it at 7.6 V.

I shut off the car, connected a 6 A 12 V car battery charger to the battery without disconnecting it from the LEAF (started drawing the full 6 A) and went to work in the usually-neglected ICE car. On our return after 8 hours, the charger was down to near zero charge current. I pulled it off and tried to start the LEAF, hoping to make a test-drive around the block, but no luck. The T/M display was gone but the display looked like this:
IMG_1269 by wagen13, on Flickr
The voltage on the little battery with the LEAF shut off is now 12.47 V

Any suggestions other than "tow it to the dealer?"

Original battery after 7 years? Replacement time, if that's the case...

The low 12 volt triggered that code. You can try another computer reset, disconnect the now charged 12 volt battery from the car for about 5 minutes (to drain the capacitor that keeps the computer running) and hook it back up to see if it resets again to make it driveable. You will need LeafSpy to clear those EV codes (provided nothing broke) unless you want to visit a dealer and have them do it for a charge... :|

Never use Accessory Mode in the Leaf! It draws power from the 12 volt battery only, rather than having it supplied by the DC-DC converter, drawing from the main battery. It was stupid of Nissan to add this mode without explicitly warning that it should not be used for more than the radio, or at most a very few minutes of full accessory use. You need to clear the codes and replace the 12 volt battery with a new 51R battery that has been fully charged before installation.

Randy said:

Original battery after 7 years? Replacement time, if that's the case...

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No, I installed a new one in September 2017, after the battery in my Ford Taurus failed the previous month when it was less than four years old. I bought a new 2001 Subaru who's battery also failed after four years, so either I have terrible luck or 12 V batteries can't be trusted.

My policy is to replace them at around four years, as a result of these experiences. Amortizing the small cost of a 12 V battery out over one more year isn't worth the worry, IMO. So, I wasn't quite ready to replace the one in the LEAF, but not TOO much longer.

LeftieBiker said:

Never use Accessory Mode in the Leaf! It draws power from the 12 volt battery only, rather than having it supplied by the DC-DC converter, drawing from the main battery. It was stupid of Nissan to add this mode without explicitly warning that it should not be used for more than the radio, or at most a very few minutes of full accessory use.

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Yeah, I'd kinda gotten that message from this experience. I'd assumed the DC-DC converter was active in accessory mode, but that was stupid and I should have checked it by looking at the voltage on LeafSpy.

I *might* have the 12 V battery tested at the nearby auto parts store to see if I can eke out another year from it, but that's probably asking for trouble...

So, a while after my OP and three or four hours after I'd disconnected the 12 V battery charger, I decided to try the foolishly hopeful test of the "maybe it fixed itself while I did nothing" hypothesis, just before going to bed. That actually seems to have worked, and I was able to drive around the block! I then immediately went to sleep, so I hope it still works this morning.

Between the second photo in the OP and that trial, I did nothing that I can remember other than turn off the car, lock the doors, then unlock them three hours later and start it up as normal. WTF?

Later this morning, I'll probably go ahead and disconnect the battery for 15' to let the computer shut down for real (which would give me time to get out the Zefal floor pump and finally re-air the tires, which have dropped below 40 PSI between the cooling seasonal temps and MANY months of neglect), then hook it back up and see if I can clear the codes in LeafSpy.

Is there a URL somewhere to a version of the LeafSpy Help screen that I can look at on my laptop? A quick search didn't turn it up. I can't even remember how to open the Service screen without staring at the Help screen. It would be nice not to have to hop back and forth between the app and the help screen on the phone while using it.

It depends upon the error code(s), but I have sometimes seen the yellow car with exclamation point symbol come on from a charger malfunction and have it clear after just power cycling the car a couple of times. If your 12V battery is holding a charge now, it will probably be OK for a while since you did not leave it deeply discharged for extended time.

To enable the service screen in Leaf Spy:
1. Touch the 3 little bars in the upper right corner.
2. Touch "Settings".
3. Touch the "enable" check box for Service Screen.

LeftieBiker said:

It was stupid of Nissan to add this mode without explicitly warning that it should not be used for more than the radio, or at most a very few minutes of full accessory use. You need to clear the codes and replace the 12 volt battery with a new 51R battery that has been fully charged before installation.

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I agree 100%, but I think they sorta tried because it shuts off after 30 minutes automatically, which if it was just the radio, might not be too bad, but if you have the seat warmer, fans, etc. going then yeah, dead battery within 20 minutes or so

I hope this is the right place for me to ask this question. I have a 2014 Leaf and after being gone about 3 months I went to start the car and nothing, absolutely nothing. I believe the OEM battery is probably toast and if the easiest thing to do is just replace with a new one, that is what I will do.

I called the dealership who suggested that I tow the car to them because only they can install the battery and reset all the systems. Is this true? Or could I just replace the battery myself (I understand the new battery needs to be fully charged) and then hope for the best? If I do get some kind of "codes" or such, would it then be necessary for me to drive the car to the dealership to have them do the resetting, or could I see if I could find a mobile mechanic who has a LeafSpy or some other kind of tool that could do essentially the same job?

Seems kind of crazy for me to have to either tow the car AND then pay over $250 just because the 12v battery has gone bad/dead. Please, I'm a newby and any advice on what I can and should do from here would be very appreciated. Thank you so much.

BuckMkII said:

Is there a URL somewhere to a version of the LeafSpy Help screen that I can look at on my laptop? A quick search didn't turn it up.

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There are directions at the top of the help on how to email the author for a PDF of the help file.

Amazing1 said:

could I see if I could find a mobile mechanic who has a LeafSpy or some other kind of tool that could do essentially the same job?

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I think the car will start and drive once the 12V battery is replaced. After that you can decide how to proceed. I'd suggest getting LeafSpyPro for yourself, it will cost about $30 in total and is well worth it, IMHO. The codes may reset by themselves but if not I'd guess most mechanics with an OBDII tool could reset them although some codes seem to be more persistent and might require several passes to clear completely. Finally, consider getting an AGM style battery since they are better suited to the needs of a Leaf (no starter motor and no alternator). BTW, a Leaf uses a 51R group size battery.

To directly answer the question: you can replace the battery yourself, if you have enough experience to do so with a normal car. It's virtually the same as with a modern ICE car. Be careful with the positive terminal and cable.