EV system warning only when accelerating

[ajmoser80]

I have a 2017 leaf and it has seemingly randomly, started to have issues.

While driving on the freeway, I was accelerating from about 55mph to almost 60 when the car started beeping, showed the EV system warning light, and stopped accelerating.
It then would not respond when trying to use the accelerator pedal and a message appeared on the screen asking to stop the vehicle immediately.
I did this and started taking a video.
The car showed a battery symbol in the middle of the screen and then the message changed from stop car immediately to "apply parking brake".
While it was beeping and asking me to apply the parking brake, the turtle symbol and the EV system warning symbol were both illuminated.
Once I applied the parking brake, the beeping stopped, both the turtle light and EV system warning light stopped, and I was once again able to accelerate normally.

This has happened randomly a few times since then. The only similarity that I can think of is that it happens only when accelerating. The speeds have varied anywhere from about 40mph to nearly 70. Each time, it asks to stop the car immediately and once stopped, asks to apply the parking brake at which point it goes back to normal as if nothing happened.

Has anyone else had these symptoms before with their leaf?
I have put about 7000 miles on it in the year that I have had it.
I have not taken it to a nearby dealer yet.
After seeing so many other threads saying dealers were not able to figure out what is wrong with their leaf, I just worry that they won't be able to help me either.

Sorry can't think of any other information that may be useful in figuring this out.

 

[LeftieBiker]

Welcome. The two main suspects, IMO, are the 12 volt battery being near Dead, and the main traction battery having one or more weak cells. The latter is fairly common for the 30kwh battery, and the former happens with all Leaf years, although usually not in that specific way. You need to take a LeafSpy Pro reading of the main battery, using the app and a Bluetooth diagnostic port dongle like the one in my signature. You should also read the rest voltage of the 12 volt battery: pop the hood, turn the car off, and 30+ minutes later open the hood without opening the car door, and use a multimeter to read the voltage between the 12 volt battery terminals. If it's below 12.2 then you likely have a dying accessory battery. Higher readings are possible with a weak battery, but usually the voltage will be low.

 

[ajmoser80]

Wow thank you so much for the quick reply.

So here is what I have done to try and figure this out already.

I did get an OBDII dongle and installed leafspy lite as well as another app called car scanner.
I also purchased a battery load tester.

There were no DTC's from the car scanner app and since I haven't taken the plunge with leafspy pro yet, I can only see that my state of health of my 30KW is approx 84% and all the cells look even in the graph.
The battery load tester says my car battery (accessory battery) is at 100% health.

I am definitely interested to try the whole door opening thing. Is that like the difference between a soft and hard reset?
Sorry I didn't think to add this earlier.
Thank you again for all the info.

 

[LeftieBiker]

The door thing is just to get the most accurate voltage reading. What number is Leafspy displaying in large font, with "mv" after it?

 

[DaveinOlyWA]

Sounds like a weak cell. Turtle mode is voltage triggered and only needs ONE cell to drop low enough. Weak cells show up under load so a weak cell combined with a higher demand for power could be your culprit. Several posts on FB, YT, etc showing the same thing. Most issues cleared by simply power cycling the car. One shows someone going from 65% SOC to 35% in a few miles, hitting shutdown and power cycling back to 60% SOC...

How many capacity bars have you lost?

Do you have LEAF Spy logs to look at?

 

[Stanton]

This has nothing to do with the 12v battery (car is in "ready" mode).
I'm assuming this is a 30 kWh battery pack...which are known to be problematic. Everything screams a bad cell, and the OP will have to do some detective work (with LeafSpy) because it's probably a long way from throwing DTCs (but dangerous never-the-less).

 

[LeftieBiker]

This has nothing to do with the 12v battery (car is in "ready" mode).

We have had a couple of cases where the 12 volt battery was so bad that it acted as a resistor, and bricked the car while it was being driven on the highway. I agree that this is not the case here, but it's an easy problem to rule out.

One very low cell can be easy to miss on the cell histogram - especially on a small phone screen - so the highest differential in millivolts will be very helpful, especially if the reading is taken at a lowish state of charge.