Sudden turtle at 55% SOC -2F

2017 Leaf S, Minneapolis MN. Almost 3K miles in 3 months. No problems so-far (knock-on-lithium).

My wife took the leaf for a short (2 mile / 3km) drive to an appt. this morning. Temps were about -2F / -19C . She texted to ask what the turtle meant ( :shock: ). She reports that the dashboard SOC says 55%, so I’m not sure.

Last trip was 10 mi./ 16km (round trip) last night, no problems noticed.

l will plug-in leafSpy when she gets home. I’m thinking I should take it to the dealer. I wonder if I should try to take it to the dealer before charging it? Or charge it at home, then take it to the dealer?

I had nearly the identical situation happen to me as well yesterday morning, and have a thread going here:

http://www.mynissanleaf.com/viewtopic.php?f=30&t=25071

Taking it to the dealer tomorrow morning to see what they find. Not super happy about the issue, but hopefully it is an easy fix and kinda glad to hear I am not the only one!

Jason

specialgreen said:

2017 Leaf S, Minneapolis MN. Almost 3K miles in 3 months. No problems so-far (knock-on-lithium).

My wife took the leaf for a short (2 mile / 3km) drive to an appt. this morning. Temps were about -2F / -19C . She texted to ask what the turtle meant ( :shock: ). She reports that the dashboard SOC says 55%, so I’m not sure.

Last trip was 10 mi./ 16km (round trip) last night, no problems noticed.

l will plug-in leafSpy when she gets home. I’m thinking I should take it to the dealer. I wonder if I should try to take it to the dealer before charging it? Or charge it at home, then take it to the dealer?

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Also in MSP but with a '13 and I've never had that happen, even yesterday while the range was severely impacted by the cold weather(<50 mile range reported) I never had the turtle issue. Note I was missing a bubble or two of regen, even in mid SOC's, still I had all bubbles of power. I'd take it to the dealer, preferably in the morning when it's cooler, -10F lately

The beep+turtle happened about 1/3 mile after leaving home, driving on level ground at 30 mph. My wife drove a mile further, parked the car for two hours, and when it was started, the turtle was gone.

Her drive home was normal. I drove it on an errand, and everything was normal.

I charge about every other day to 90%, and once per week I charge to 100%.

I uploaded Leaf spy screens to Dropbox :

https://www.dropbox.com/sh/wwsh0psbd7ianau/AADsSQavWhF7oDOrhq6rPDkya?dl=0

Did you check for trouble codes? The cell voltage graph looks normal. The other three screen shots are not really valid because Leaf Spy was not communicating with adapter (note yellow communication status boxes). It is under warranty so make it the dealer's problem to solve.

GerryAZ said:

Did you check for trouble codes? The cell voltage graph looks normal. The other three screen shots are not really valid because Leaf Spy was not communicating with adapter (note yellow communication status boxes). It is under warranty so make it the dealer's problem to solve.

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+1

I took it to the dealer on the way to work. They reported one "past" code: "control module over temperature." They said this was probably due to a assembly problem: the factory routing of a coolant hose was sometimes kinking, causing temperature problems. They rerouted the hose, and sent me on my way to work.

The invoice says "Cause: CD18AA RPL LOWER RADIATOR HOSE" AND "3041 RADIATOR HOSE IS NOT ROUTED CORRECTLY" and "POSITIONED LOWER RADIATOR HOSE PER BULLETIN". There's no mention of the exact DTC or TSB. I will call them and see if I can get that tomorrow.

It does seem a little odd that a module would overheat 1/3 mile from home, on a -2 degrees F day, after being parked outside (and not plugged-in) overnight... versus, say, last September when I fast-charged it at 84F ambient. My suspicion is that the DTC was not recent, and maybe the dealer had no idea why we saw a turtle, but wanted to "be responsive to the complaint." I'm ok with it, because at-least the dealer has a record of "sudden turtle onset" (SDOS) within warranty.

Good point on the record. Make sure that you keep your copy.

Well, I got a second occurrence of Sudden Onset Turtle Syndrome. I had parked the car overnight in the street, low of -14F. I went out to move it to the charger before I left town, and got an immediate turtle at -10F. Leafspy screens show 66% SOC, 1 degree F battery temp, but 34mV max cell delta.



Unfortunately, I left town with both keys in my suitcase, so the leaf sat there, forlorn and unplugged, for 4.25 days. Over that time, ambient temps were (low/high): -14 / -6F , -5/-16F , -13F / +1F, -10F / +12F, +0/+6F

The car was parked with no protection; weather was cloudy; and the car is white. So I was expecting that the 300W battery heater would kick-on quickly, and run for about 34 hours (10kw-hrs... until the SOC drained to 30%), then stop. After that, the pack temp would approach average ambient, which would probably be between 0F and 3F (which should be OK, as my manual says the heater doesn't kick-in until below 0F).

However, when I returned, I was surprised to find that the actual battery temp was 8F... and the traction battery had only depleted by 3 GIDs or "0.2% SOC". That could mean that the battery heater never came on at all (or my 2017 S doesn't have one?). Or that the LeafSpy-reported numbers are just wrong.



Anyways, the car has turtled twice: once 1/3 mile from home at -2F; and once immediately at power-on at -10F. In the second instance, cell balance showed 34mV delta, but after sitting for 4 days (and the pack warming-up to 8 degrees F), the cell imbalance improved to only 18 mV. So I'm suspecting that cold temperatures magnified the measured cell imbalance, triggering a spurious turtle; with a possible contributing factor of a non-working battery heater. I'm going to call it "Frozen Turtle Syndrome" instead.

34 mV for cell voltage delta is not enough to cause Turtle mode by itself. Turtle is normally caused by the lowest cell-pair voltage getting down to the threshold (which is below 3 volts) so something else is happening with your car. We have not seen a bunch of sudden turtle reports in spite of cars being driven in cold weather so Nissan needs to fix your car.

Perhaps it would be good to take a photo next time you get Turtle - a bit more proof that the problem exists if there is resistance from Nissan to making it right?

2011RedLeaf said:

Perhaps it would be good to take a photo next time you get Turtle - a bit more proof that the problem exists if there is resistance from Nissan to making it right?

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Oh, right, I did get that:

GerryAZ said:

Did you check for trouble codes? The cell voltage graph looks normal.

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I checked DTCs with LeafSpy; even though the dash was displaying the turtle, plus red and yellow "warning" triangles above, all the modules say "Ok None --> " for DTCs. I will throw my CRP128 ODB2 scanner in the car, and if it happens again, I'll also check for codes with that.

It sounds like it's "back to the dealer" for me. So-far, it's only been a curiosity; and covering my back-side in case there is further battery trouble. But if it turtled while driving on the freeway, that could be bad.

Does the normal pack go below 360 Volts at turtle level SoC ?

SageBrush said:

Does the normal pack go below 360 Volts at turtle level SoC ?

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Pack voltage at Turtle depends upon how well balanced it is and how much current is being drawn. My 2015 normally gets below 300 volts before Turtle limits power when using climate control to drain the battery in the driveway.

Specialgreen's dash photo is interesting because it shows that regeneration is being limited along with output power. Normally, full regeneration is available when the battery is discharged enough to get close to Turtle even with severe deterioration.

Update: the dealer had the Leaf for four days during a subzero cold spell, and couldn't re-create the problem. They reported that there were zero errors in the computer (does LeafSpy delete them automatically?).

They suggested that next time it happens, it would help if I could drive to the dealer without shutting the car off, so they can get it on the Consult.

They want you to drive to the dealership in Turtle Mode? :shock: :|

Nubo said:

They want you to drive to the dealership in Turtle Mode? :shock: :|

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Yes, it sounds crazy.

On the other hand, My wife did drive it for 5 minutes after getting the turtle with no trouble; and both times it turtled, the car was fine again after turning it off and waiting. So they think it's a false alarm, and the car could drive all day (at 30mph). I also checked it with LeafSpy, and with the turtle showing, the battery cells had 34mV delta, which sounds not-perfect but OK.

The route to the dealer is roughly my normal daily commute, and I take surface streets when traffic is bad anyways.

I had something very similar. Also crazy cold and the first thing I noticed is that the regen wasn't going past two bubbles. Then I noticed as I try to accelerate that it wouldn't go all the way up on the right side. Then it turtled at 79%. I managed on two separate occasions to turtle at 76% and 79% but it immediately went back to normal after a few moments.

I've also enjoyed this: a 20% drop in battery over the space of a half mile and then I get it all back a few minutes later. Freaked me out to go from 70% to 50% all of a sudden. I mean it was counting down by 3 or 4% at a time. but I got it back just as quickly. I've lost 2 bars so far and have over 95k on my 2013 but this is the first winter I've had this happen.

At what temp does the battery pack heater come on? I would think at -2°F, it would be on but it's probably at right around that temp.

It's too bad it's not possible to turn on the pack heater manually, bet that would take it out of turtle.

Wonder if @Turbo3 could change the set point via LeafSpy?

Otherwise, perhaps charging on CHADEMO for 10 minutes would warm up the pack enough to get it out of turtle mode.

The dash picture does not make sense in the fact that the dash gives 91% charge, with only 63 miles range on the GOM.

On a new car with only 3K miles, it looks like the car is measuring a lot lower capacity than the % gauge indicates.

If the car then had only 50% charge, the car could be "seeing" a really low battery capacity and go into turtle mode?