Leaf won't operate. Warning - Service EV System, Warning - Service EV System Unable to restart after power off

[knightmb]

If testing the isolation at the center disconnect on the HV battery shows no issue, can there still be another possible isolation problem? My 2022 leaf keeps throwing the same start inhibition and HV battery isolation codes (P31E7 and P0AA6 EVC157) every time I charge my car and it reaches 86%. The EV Service warning message only comes on at that point, otherwise I can drive and charge my car normally once I clear the codes with my leafspy. I won't get the errors until I charge my car again and it hits 86%. My husband tested the voltage at that back seat access point and found no isolation issue, the voltage reading dropped steadily as normal. Any advice would be greatly appreciated as we live in The Bahamas and there is no Nissan EV service available.

That would suggest that you do indeed have a real issue. Somewhere in the battery pack, thermal expansion during charging is touching the outside of the shell. The best way to test this and be certain; have everything ready to measure the isolation voltage the moment it charges to 86% and the error occurs. Then you will be about to see if a voltage is remaining after the capacitance is slowly leached away by the measuring equipment while the battery is still warm.

 

[Bombastinator2]

*imagines the ending of the movie “Nosfreratu” The silent one. Then imagines the movie “Cars”*

You’ve got to set a trap and catch it in the light.

 

[aant]

Yay, this is happening to our 2018 Leaf now. Just over 100k miles, too (around 100,200). The message came up this morning right after leaving the house and we turned around and went home, tried to restart it and it's not really starting. I did replace the 12v battery in January (several months ago), so that should be good. That was around the same time the charging cable that came with the car stopped working and I replaced it with another one (could the new cable be doing something?). I'm in socal and have generally only charged to 80-90%, although last night I did let it charge to 100% because we were going to drive more today. Haven't pulled codes yet. I don't have a Bluetooth reader so can't use leafspy. Will any dtc reader work? (We're out for the day so haven't gotten back home to try more yet, but thought I'd post here for any other ideas while I'm waiting)

I made an appointment with the dealer already and assuming I'll need to tow it in Tuesday morning. Bummed, we were just talking about how reliable our Leaf has been!

 

[Jerrymander]

My Leaf displayed Warning Service EV System, Warning Service EV System Unable to restart after power off. tonight. Battery is 100% charged according to the dash display but the Battery symbol at the top right side of the dash is illuminated as are the warning lights for front and rear hazards.
The vehicle is a 2021 Leaf S Plus. I have 88K on the odometer and have never had anything other than tires installed. My battery pack does seem to be degraded and only shows 180-190 miles range when fully charged. (New was 230 Miles). Any advice on what to do here?

I've heard tell that your 12V "car" battery may be bad. The car needs it to run the systems and won't start if its low. Try getting a jump. Good luck.

 

[Bombastinator2]

I've heard tell that your 12V "car" battery may be bad. The car needs it to run the systems and won't start if it’s low. Try getting a jump. Good luck.

That is the first answer with that kind of warning. If you’ve got a trickle charger you can probably throw it on the thing and make it work. Whether it will do it NEXT time of course is an open question. The problem is batteries are a bit like balloons. They start at a voltage higher than 12v, and are empty at a voltage lower than 12. The leaf requires 12v or more all the time or it gives that reading. This is why some people put LiFepo4 batteries in them. Those are 12.8 till the bitter end. Theyre really expensive though.

Might make sure it actually is the battery. Put a multimeter on it and if it’s less than 12v, well there’s your problem.