12V Battery problems

My 2011 Leaf has worked fine since I bought it in March 2014. It was fully charged last night when I put it in the garage.

This morning, I couldn't get in - the door locks weren't working. I opened the door with the emergency key, but nothing inside the car was working either.

I arranged to have the car transported to the local Nissan dealer, but before that the fellow tried his "jump start" battery across the Leaf's 12V battery. It said "low battery" before he turned on the jump start battery. When he turned on the jump start battery, the car sprang into life. The jump battery almost immediately showed the car battery to be healthy.
Presumably, turning the car on caused the DC-DC charger to help out the car's 12V battery.

I wonder if the car 12V battery has failed, or is failing. That would explain the symptoms.

I'm going to await what the dealer's service department finds, but does anyone here have any other ideas?

I don't have a answer, but a question instead. I just leased a 2015 'S' 3 weeks ago. Emergency key? I only have the button on the door handle, wonder should this happen how do you get inside then?

Swifty said:

..but before that the fellow tried his "jump start" battery across the Leaf's 12V battery. It said "low battery" before he turned on the jump start battery. When he turned on the jump start battery, the car sprang into life. The jump battery almost immediately showed the car battery to be healthy.
Presumably, turning the car on caused the DC-DC charger to help out the car's 12V battery.

I wonder if the car 12V battery has failed, or is failing. That would explain the symptoms.

Click to expand...

Well, clearly the 12v battery was low. How it got there is the question really - it is supposed to be charged from the main traction battery but many of us have had lapses in that area.

IF your 12v battery has gotten weak then it would make sense for it to be easier to fall into this bad state so you may well have a weak 12v battery that is exposing a marginal recharge algorithm.

As to the jump battery report - I think you are correct, as soon as the car's computer came to life it realized a charge was needed and started the charge cycle which pushed voltage up where the jump battery was happy. Question is why didn't the car realize it needed charging before it fell to critical/failure levels....

recmob said:

I don't have a answer, but a question instead. I just leased a 2015 'S' 3 weeks ago. Emergency key? I only have the button on the door handle, wonder should this happen how do you get inside then?

Click to expand...

On my 2013 model there is a key hole on the door handle. The key is integrated into the remote/fob and can be pulled out. If they changed this for the '15 model then I don't have an answer....

Slow1 said:

recmob said:

I don't have a answer, but a question instead. I just leased a 2015 'S' 3 weeks ago. Emergency key? I only have the button on the door handle, wonder should this happen how do you get inside then?

Click to expand...

On my 2013 model there is a key hole on the door handle. The key is integrated into the remote/fob and can be pulled out. If they changed this for the '15 model then I don't have an answer....

Click to expand...

My 2015 still has the emergency key built in to the back of the fob. Move the little button and the square piece slides out with the key.

Swifty said:

I wonder if the car 12V battery has failed, or is failing. That would explain the symptoms.

I'm going to await what the dealer's service department finds, but does anyone here have any other ideas?

Click to expand...

Looks like your thread got "hi-jacked", so I'll answer the OP's question: if the 12v battery hasn't already failed, it's on its way. I would either replace now or watch very closely. If you want to put an end to the 12v battery hassles, see my blog post on replacing it with a Lithium 12v battery at http://stanton.myevblog.com/2012/01/16/getting-the-lead-out/" onclick="window.open(this.href);return false;

Sorry for the hijacking. But to anyone else reading this the 2015 is the same. Guess I so used to just pushing the button didn't see the key hole. The 'forest for the trees thing'. I saw the slide on the back of the fob, thought it was for opening the fob for battery change.

Boy I need a day off!

Slow1 said:

recmob said:

I don't have a answer, but a question instead. I just leased a 2015 'S' 3 weeks ago. Emergency key? I only have the button on the door handle, wonder should this happen how do you get inside then?

Click to expand...

On my 2013 model there is a key hole on the door handle. The key is integrated into the remote/fob and can be pulled out. If they changed this for the '15 model then I don't have an answer....

Click to expand...

Swifty said:

My 2011 Leaf has worked fine since I bought it in March 2014. It was fully charged last night when I put it in the garage.

This morning, I couldn't get in - the door locks weren't working. I opened the door with the emergency key, but nothing inside the car was working either.

I arranged to have the car transported to the local Nissan dealer, but before that the fellow tried his "jump start" battery across the Leaf's 12V battery. It said "low battery" before he turned on the jump start battery. When he turned on the jump start battery, the car sprang into life. The jump battery almost immediately showed the car battery to be healthy.
Presumably, turning the car on caused the DC-DC charger to help out the car's 12V battery.

I wonder if the car 12V battery has failed, or is failing. That would explain the symptoms.

I'm going to await what the dealer's service department finds, but does anyone here have any other ideas?

Click to expand...

There are various possibilities. LEAF can be hard on 12V batteries so if it's the original 2011 battery I'd say it's time for a new one. Especially since it has been run flat. Running a conventional automotive 12V battery flat can weaken it substantially. Combine that with a battery that may already be near the end of its service life and you're running on borrowed time.

Possibly something in the car was drawing additional power. The two most common causes are probably
1 - the hatch not being fully closed
2 - the infamous "double-tap" of the start button that leaves the car in accessory mode instead of turning it off.

The other thing that some people have run in to is loose terminal connections at the battery. This can simulate a "dead battery" Your experience of the battery "immediately showing healthy" upon the jump makes this sound like a possibility.

As far as charging problems, failures of the DC-DC converter are fairly rare.

Personally I'd put in a new battery and then check the voltage with a cheap multimeter over several days. If it doesn't weaken appreciably over a few days the problem is solved.

I keep my interior light off at all times just in case the doors don't shut completely, also if I'm gone for more then 4 days, I leave a battery tender hooked up to the battery. 2011 original battery shows 13 Volts, these should last over 7 years due to no cranking power or strain on them.

Fred

Wennfred said:

2011 original battery shows 13 Volts, these should last over 7 years due to no cranking power or strain on them.

Fred

Click to expand...

You'd think so, but they often don't due to various idiosyncrasies that can result in deep cycling. High depth of discharge is much more of a strain on automotive batteries than delivering the short bursts for starting. A deep-cycle AGM is far better suited for LEAF, imho.

http://www.mynissanleaf.com/viewtopic.php?f=27&t=11094&p=257210" onclick="window.open(this.href);return false;

FWIW, Tesla is using deep-cycle batteries for their 12V systems.

Nubo said:

You'd think so, but they often don't due to various idiosyncrasies that can result in deep cycling. High depth of discharge is much more of a strain on automotive batteries than delivering the short bursts for starting. A deep-cycle AGM is far better suited for LEAF, imho.

Click to expand...

I'm not familiar with the abbreviation "AGM", is it "Absorbed Glass Mat"?

It occurs to me that I didn't leave my Leaf on charge last night (unusual) so if I'd left anything on, that would have flattened the 12V battery.

I suspect that the local Nissan dealer will find no fault, but still suggest a replacement 12V battery, so I'm going to have to make a decision soon. I don't suppose it makes much difference what is fitted. It hasn't caused any damage (AFAIK), and I'll know how to overcome the problem, should it recur (I'd use a battery charger instead of a jump-start battery).

Thanks for the suggestions!

If the 12V was the original I am surprised it made it this long.
Mine was replaced under the three year / 36,000 mile warranty at the two year mark at no cost.
But it had cycled way too much using On mode.
Don't ever use anything but Ready mode.
Both Aux and On are bad for the marginal 12V charging protocol of the LEAF.

Wennfred said:

]2011 original battery shows 13 Volts, these should last over 7 years due to no cranking power or strain on them.
Fred

Click to expand...

I don't know of ANY lead acid battery that lasted 7 years, especially in a car (cranking or not).

TimLee said:

Both Aux and On are bad for the marginal 12V charging protocol of the LEAF.

Click to expand...

Not if you replace that lead acid battery with a Lithium! I've listened to the radio for hours and left my Leaf sitting at the airport for days and NEVER had a problem (with a 12v LiFePO battery)

Stanton said:

Wennfred said:

]2011 original battery shows 13 Volts, these should last over 7 years due to no cranking power or strain on them.
Fred

Click to expand...

I don't know of ANY lead acid battery that lasted 7 years, especially in a car (cranking or not).

Click to expand...

I have had good success with mine here in San Diego. 2001 Honda Civic, 5 - 7 year life on these lead acid batteries. Could be the weather and also keeping them clean at all times.

I just replaced one after 7 years, blew me away how time flys.

Plano Tx, I assume it gets very hot there?

Fred

Stanton said:

Wennfred said:

]2011 original battery shows 13 Volts, these should last over 7 years due to no cranking power or strain on them.
Fred

Click to expand...

I don't know of ANY lead acid battery that lasted 7 years, especially in a car (cranking or not).

Click to expand...

Probably not in TX, but in cooler climates it's possible. One of the reasons I fell in love with AGM was the original battery fitted to the 1990 Miata. It was an AGM from Panasonic. When I first saw it I thought it was absurdly small and would surely die a premature death. But it was a fantastic performer compared to any car battery I'd had. It lasted 9 years.

TimLee said:

Don't ever use anything but Ready mode.
Both Aux and On are bad for the marginal 12V charging protocol of the LEAF.

Click to expand...

More terms that I'm unfamiliar with...

My handbook documents four power switch states: OFF, ACC, ON/READY and LOCK
I presume that "AUX" and "ACC" are interchangeable terms.
I can't see any difference between ON and READY, or any way to change between them. Is this because my Leaf is a 2011 model?

Incidentally, I don't know how to distinguish between OFF and LOCK. I suspect this might explain why my Leaf beeps when I try to lock it with the keyfob (but it will lock with the door button)

Swifty said:

More terms that I'm unfamiliar with...

My handbook documents four power switch states: OFF, ACC, ON/READY and LOCK
I presume that "AUX" and "ACC" are interchangeable terms.
I can't see any difference between ON and READY, or any way to change between them. Is this because my Leaf is a 2011 model?

Incidentally, I don't know how to distinguish between OFF and LOCK. I suspect this might explain why my Leaf beeps when I try to lock it with the keyfob (but it will lock with the door button)

Click to expand...

Yes, my bad in using term auxiliarry.
Nissan term is ACC for accessory.
Single push of the button with foot off of the brake.
Only thing active is 12 volt.
Really bad to use this as LEAF hardly ever charges the 12 volt above 13 volts, which is not fully charged for a lead acid battery.
So you are proceeding to further discharge a partially discharged battery.
This mode will shut itself off automatically after a period of time, but by then you have left the battery extremely discharged.

You get ON mode by having foot off the brake and pushing the button twice.
I originally thought this mode was acceptable because the high voltage circuits are active and when the 12 volt voltage drops it will periodically charge it up.
But waits too long.
It let's the voltage drop a long ways below 13 volts before it charges the 12 volt.
Again, very bad, and how I killed my first 12 volt battery using Nissan's badly designed ON mode.

READY is car can be driven. Foot on brake pedal and one button push.
In this mode LEAF will very briefly charge the 12 volt at 14 volts and then drop to around 13 volts.
That is still not ideal treatment of the 12 volt battery.
But it is the best the LEAF offers.
Just be sure vehicle is in Park and emergency brake is on and keep your foot off the brake and don't leave the vehicle unattended.
Yes you will use more energy from the main battery.
But isn't that better than shortening the life of the 12 volt battery :?:

The dealer should have performed a stress test. I purchased one of these to test cca along w a battery tender and a jumpstart kit.

http://www.amazon.com/gp/product/B0015PI7A4/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1" onclick="window.open(this.href);return false;

Slow1 said:

Well, clearly the 12v battery was low. How it got there is the question really - it is supposed to be charged from the main traction battery but many of us have had lapses in that area.

IF your 12v battery has gotten weak then it would make sense for it to be easier to fall into this bad state so you may well have a weak 12v battery that is exposing a marginal recharge algorithm.

Click to expand...

The Nissan dealer confirmed that the 12V battery was weak, so I requested a replacement. I've just collected the car, and it's clearly back to it's original capabilities. We'd recently noticed that the range was falling off, but that also seems to have improved again. It was only a short run, but on the old 12V battery I seemed to be losing 2 miles of range for every mile I drove; that's now fixed.