Very weird issue on my 2014 Leaf SV and Turtle Mode.

[Petec]

I've had my Leaf for 10 years and, apart from the inevitable declining battery capacity, I've been very happy with it.
Currently about 110,000 miles on the clock and about 50% remaining capacity. My situation is such that I only drive 35 to 45 miles at a time and it is quick and convenient to recharge both ends if needed, so capacity has not been an issue. I figured I could manage one more year before replacing it or getting a refurbed battery put in.

Had a few times when I've pushed it a bit on range and had the Turtle light come on about a mile from the house but no big deal. By my estimate that's happened when I've had maybe 3 miles left.

All change this week when the Turtle light came on halfway home with the battery saying 30% left and the the range saying 18 miles left. No low battery warning. No Very Low battery warning, just "your power is being limited" Got home alight and driven a few times since. Sometimes no issue. Sometime same thing.

So Leaf wizards out there - any thoughts? If it was triggered by declining cell or overall battery voltage then I can't see why I didn't get Low Battery or Very Low Battery warnings first.

I bought Leaf Spy and looked at it, little overwhelming at first! However it shows less than 20mv difference from highest to lowest cell voltage which doesn't sound all that much but then the battery has been charged since..

Pearls of wisdom welcome from anyone!

My next thought is to fully charge the battery then drive around until it happens again and then immediately pull over and look at LeafSpy

Thanks!

 

[atikovi]

You need to scan for codes. Anything else is a guess until you know the cause.

 

[cornbinder89]

You'll likely need Leafspy (or other scanner) plugged in and operating so you can see what the cells are doing in real time.
My guess is: you'll see one or more cells suddenly drop then come right back when the load is removed.
I could be wrong, but you have to see what is going on when it happens, not right after it happens.
It may take two people, one to drive and one to watch what is happening on Leafspy.

 

[nlspace]

A weak cell can drop under acceleration and then somewhat recover after, masking the issue.

But if you do a WOT acceleration run with LS connected, then it will be revealed sooner rather than later, and without running the car down too far that you might get stranded out. Plus full torque is alot of fun.

 

[Petec]

All sorted and, Duh, it was the 12V battery! Put a new battery in and miraculously everything returned to normal.
It's 5 years since I had to swap it last time and I'd forgotten and I'd forgotten that all hell breaks loose on the Leaf when the 12V is a bit low.

 

[BuckMkII]

All sorted and, Duh, it was the 12V battery! Put a new battery in and miraculously everything returned to normal.
It's 5 years since I had to swap it last time and I'd forgotten and I'd forgotten that all hell breaks loose on the Leaf when the 12V is a bit low.

Thanks for the reminder to check how old my 12V battery is!

 

[cornbinder89]

All sorted and, Duh, it was the 12V battery! Put a new battery in and miraculously everything returned to normal.
It's 5 years since I had to swap it last time and I'd forgotten and I'd forgotten that all hell breaks loose on the Leaf when the 12V is a bit low.

I'm glad your car is now working, However I am concerned that there is more going on.
When the car is in ready mode, driving the 12 volt power should be drawn from the DC-DC converter. Just like a "regular" gas engine car, if your car dies when the engine was on, it isn't the battery but the charging system that is at fault.
In both cases, replacing the battery will make the problem disappear for a while, but hasn't got to the bottom of the problem.

 

[Stanton]

In both cases, replacing the battery will make the problem disappear for a while, but hasn't got to the bottom of the problem.

The "bottom of the problem" is that his traction battery is old and worn out (as was pointed out in another post), and that reduced capacity has finally yielded a "weak" cell that resulted in a turtle. However, you are correct in that it will never "fix" itself.

 

[cornbinder89]

The "bottom of the problem" is that his traction battery is old and worn out (as was pointed out in another post), and that reduced capacity has finally yielded a "weak" cell that resulted in a turtle. However, you are correct in that it will never "fix" itself.

Not what I was responding too, He stated that replacing the 12 volt "cured" the traction battery cell drop.