Another Dead Leaf after Vacation Plugged In - Detailed Info

I realize this is at least the 3rd thread about dead leafs after vacations while being plugged in. The reason I'm not just adding to those is that they are pretty old, and have gone astray with random topics like air moisture. I would like this thread to tackle more of the diagnosis of what's really going on and to collect other reports. In the two threads I found:

http://www.mynissanleaf.com/viewtopic.php?f=30&t=8588&hilit=dead+leaf+vacation" onclick="window.open(this.href);return false;
http://www.mynissanleaf.com/viewtopic.php?f=30&t=5332&hilit=dead+leaf+vacation" onclick="window.open(this.href);return false;

when a leaf is left with the traction battery charged, off (presumably), and plugged in, the 12v battery dies but the traction battery remains the same. I also found one thread where it was left at the airport without being plugged in and the main traction battery dropped very low, which seems to be a completely different issue. My case is very similar to the first two cases.

1) On the evening of May 22nd I believe I left the car in the OFF state. I haven't ever left it in the READY state in the 8 months since I've owned it.
2) I plugged it in. I have a fancy power monitoring system, The Energy Detective, which measures exactly how much power the charger is using. I have proof that it was charged for several hours the evening before my trip. This is a KEY bit of evidence as we'll see later. The records show it charged 15.55 kwh from 9PM to 1AM on 5/23. The records also show some minor usage which could be due to the charger itself - 30 watts every 12-1AM until the 28th, then 30-40 watts per hour from midnight on the 28th til 10AM on the 29th (34 hours). It didn't use the normal 30 watts on midnight of the 30th or 31st. I suspect the battery was dead by this point.
3) On the morning of the 31st I returned from the trip and unplugged my car. It didn't respond in any way. THe only sign of life was a very feint slow flashing on the start button. I had to leave so I called roadside assistance and left the car with my wife.
4) Roadside assistance had to jump it from their truck to get it out of park and out of the garage. They were able to get it into Neutral, but not Drive or Reverse. The traction battery showed normal charge. I wasn't there to diagnose why they couldn't get it into D or R, but I suspected they weren't pressing on the brake pedal? In later experiments, however, I found that you have to press on the brake to get it into N, so I don't think that was the problem. My latest theory is that the charger was still plugged in, preventing shifting into anything but N. Roadside assistance pushed the vehicle out of the garage but had to leave the vehicle due to lack of space in my driveway.
5) When I returned home I jumped it with a battery charger with a 50 AMP starter feature. I only now read that there might be some danger to the inverter but fortunately I had no problems. I was able to jump the car and immediately get it into D and R. I put it on the charger overnight, and the next day the battery tested fine (with a 100 AMP load Harbor Freight battery tester), and everything seemed to drive fine.
6) Today I brought it to the dealer to have it checked out. They pulled a code out of the computer which they say means the car was left in ready mode! I found that highly unlikely.

If I had left it in Ready mode there are two possibilities, so I tried them both out. I am skeptical I left it in Ready mode.

Theory 1) I drove it into the garage, put it into park, exited the car, and plugged in the charger while still in ready mode. I tried this out tonight. The result when you plug in a car in Ready mode is that the car shuts most of itself off (engine fans go silent) but stays in ready mode. The death blow of this theory is that the charger will NOT charge. It says "Ready to Charge". Since I have proof that the charger was charging for several hours afterwards this cannot be. Page CH-4 supports this "if the charger is connected to the vehicle while the power switch is in the READY to drive position, the vehicle will automatically switch to the ON position. Because charging will not be started while the power switch is in this position, be sure to place the power switch in the OFF position".
Theory 2) I turned the car off, then plugged in the charger, and then re-entered the car and turned the car on. I tried this out tonight. The result when you turn on a car being charged is that if you simply press the start button with or w/o the brake pedal the car doesn't enter Ready mode (the left-right arrow never appears). Instead, you are left in a state indicated by a plug icon. While this may seem like a technicality, the Leaf techs were very clear about the car being left in "Ready" mode.

So, my conclusion is that the car was NOT left in Ready mode, and the code that the Leaf generated code about low battery is not specific to Ready mode. It's slightly possible but very unlikely that it was left in "plugged in" mode (not sure what the official term is).

I would also like to point out that despite what the techs and my salesman says about the Leaf not charging the 12v while in Ready mode page EV-5 of the manual says EXACTLY that! "The Li-ion battery charges the 12-volt battery as necessary when the power switch is in the READY to drive position". Further, it says "the 12-volt battery charges automatically for 5 minutes every 5 days. The charge timing resets to 5 days without charging the 12-volt battery if -The vehicle is place in the READY to drive position for more than 5 minutes or - The Li-ion battery is charged for more than 5 minutes". This means that in READY the 12v *is* charged. While OFF the 12v is charged every 5 days. The READY mode will delay the OFF mode charging for 5 days, but it should still charge the 12v while in the READY mode.

I also found this paragraph CH-9 "If a charge connector is connected while charging is not being performed, when the power switch is placed in the ON position and the selector lever is operated, it is only possible to switch from P to N". This is probably the situation my wife found after jumping - they jumped it in the garage and may not have disconnected the charge cable. When I found the car in the driveway disconnected, jumping immediately allowed me access to D and R.

Bottom line, I think there's a bug in the Leaf software. I think I and the others left the car in the OFF mode and plugged in charging. There must be a bug that while left plugged in, the 5 day timer isn't working and the 12v is draining. My energy meter also shows an unusual 30-40 watt/hr drain for 1.5 days starting at 5 days after leaving it - I wonder if this is a symptom of the problem. I can't afford to leave my leaf for 5 days to see what happens, and understandably dealers don't want to tie up a car & charger for 5 days. My advice is to not leave the car plugged in for extended periods of time.

gonefishin said:

1) On the evening of May 22nd I believe I left the car in the OFF state.

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gonefishin said:

I am skeptical I left it in Ready mode.

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(both snipits probably out of context by themselves)

I read it all but still come back to these two. Unfortunately we get out of our routine when leaving for a while and I know I make mistakes. I wish you could say with absolute certainty LEAF was off. I really think the most important is to go back and verify LEAF is off off. Even to the point of writing it down verified. Secondly I like a short charge daily or weekly (80% max) depending on length of the trip.

One answer is go measure it.

There are voltage logging devices that can measure and record the 12Volt battery. See http://www.mccdaq.com/usb-data-acquisition/USB-500-Series.aspx" onclick="window.open(this.href);return false;

You could also build one with an Arduino or use a data logging DVM.

I am currently on a 14 day vacation with my Leaf plugged in at the airport. To avoid the dead Leaf syndrome when I return, I set the timer to charge for 20 minutes only each day. I left the car with ~20% SOC and it should reach 80% the day before I return. Before our flight back, I will manually initiate a charge to 100%.

I believe this will charge the 12V battery each day so everything should be topped off when we return.

gonefishin said:

Bottom line, I think there's a bug in the Leaf software. I think I and the others left the car in the OFF mode and plugged in charging. There must be a bug that while left plugged in, the 5 day timer isn't working and the 12v is draining.

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The issue is that the car doesn't top off the 12v battery on schedule (approximately weekly) when it's plugged in.

The small power draw you saw daily for 5 days was likely the car starting to charge briefly as you hit the timer start time, but the car decided it was full so stopped charging immediately.

gonefishin said:

My energy meter also shows an unusual 30-40 watt/hr drain for 1.5 days starting at 5 days after leaving it - I wonder if this is a symptom of the problem.

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By now the 12v battery was low/dead - I suspect that the car started resetting itself frequently until it completely died.

gonefishin said:

My advice is to not leave the car plugged in for extended periods of time.

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General advice when leaving the car for more than a couple days:

1. Do not charge to more than 80%. 40-60% is ideal. DO NOT CHARGE TO 100%.
2. If you need the car to charge while you're gone, set the charge timer to charge for a short period of time each day so that it reaches full when you return. Depending on your length of vacation, you'll typically set a short charge time period (20-30 min) anywhere from daily to 2-3 times a week.
3. If going to be long for a very long time, disconnect the negative post of the 12v battery (wait 5 minutes before doing this, but not more than an hour) and put it on a battery tender.

I don't understand why everyone is trying to make this so complicated. As gonefishin says, there does seem to be an unintended glitch, but the bypass is simple:

• Make sure that you turn the car OFF. (After you lock it, look in and double-check that the console display is black.)
  • I suspect that gonefishin may have accidentally left his car in AUX mode. I've had that happen to me when I jittered the power button - two quick clicks and it goes to OFF, then ACC. The dash will be black, but (after a few seconds) the console will light up again.
• Don't plug the car in.
• Leave the traction battery at 40% to 80%. It will be fine for many months.
• For 2 weeks or less your 12v battery will also be fine, no matter what. I think it will be fine for longer periods, since the glitch only seems to occur if the car is plugged in, but if you want to be double-sure, provide some kind of trickle charge for that battery.
  • If it is outside and you have the normally useless solar panel on the spoiler, that should be enough.
  • If it is outside and you have an SV, put a $30 solar trickle charger on top of your dash.
  • If it is inside your garage, hook a $20 powered trickle charger to your battery.
  • If it is inside a public garage, you will have enough 24-hour light that the "outside" solutions should work.

Ray

planet4ever said:

*]For 2 weeks or less your 12v battery will also be fine, no matter what. I think it will be fine for longer periods, since the glitch only seems to occur if the car is plugged in, but if you want to be double-sure, provide some kind of trickle charge for that battery.

• If it is outside and you have the normally useless solar panel on the spoiler, that should be enough.
• If it is outside and you have an SV, put a $30 solar trickle charger on top of your dash.
• If it is inside your garage, hook a $20 powered trickle charger to your battery.
• If it is inside a public garage, you will have enough 24-hour light that the "outside" solutions should work.

[/list]

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Ray, great post. Another approach is to simply disconnect the 12V battery to prevent any load on it. This was mentioned before, and I believe that it's also recommended for the Volt. Given the recent battery degradation debate, I would not charge the traction battery to more than 60%. The self-discharge rate is extraordinarily low, especially if the 12V is taken care of via a trickle charger or disconnect.

Remember that you can not plug it in the the cigarette lighter though since that is disconnected when the car is off...

surfingslovak said:

[*]If it is outside and you have an SV, put a $30 solar trickle charger on top of your dash

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planet4ever said:

I don't understand why everyone is trying to make this so complicated. As gonefishin says, there does seem to be an unintended glitch, but the bypass is simple:

Don't plug the car in.

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Doesn't work when the car is parked at the airport with 20% SOC remaining and we need it at 100% to get home again...

1) if you had left it in ready mode, the 12 volt battery would have remained charged

2) if you had left it in ready mode, there would have been greater than a constant draw of 30 watts.

3) the code reset by the dealer was probably due to what Roadside did.

4)i doubt that you did any major harm to your pack although charging it the night before you left is suspect. i am guessing it charged to 80%? but you were only gone 10 days so next time, now ya know how to do it. charge it to 50% and leave it unplugged. you will be fine

Pardon my ignorance and I know carwings isn't the best in the world but wouldn't that history show something about the ready/not ready and running report of the SOC?


2 cents and complimentary pick axe to poke holes.

Thank you to all the responses. Yes, there are workarounds. The reason I'm "making this so complicated" is that I'd like to find this bug and get it back to Nissan for fixing, and this forum has the resources to do that. If you don't want to help, that's fine - let us crazy engineers talk amongst ourselves. It's bad for everyone including us current owners if Nissan / EVSE manufacturers don't fix this aThnd a lot of leaf owners start having problems. Where there's smoke, there's fire. Perhaps I'm one of only 3 people to have ever experienced this but I believe this to be widespread and would like this thread to examine it. When I talked to the dealer they say that most of these dead batteries are because cars are left in READY mode. I've already proved that I wasn't in READY mode and that according to the manual, you can't drain the 12v alone in READY mode. The dealer is wrong. We have the power with hundreds of users to find out what's right.

Can someone actually say they've left their leaf OFF and plugged it in for 8+ days and had no problems?

I hope we do hear back from jkirkebo who is leaving their car plugged in at the airport. His post raised an interesting point about charge timers. I have an 80% timer only, and I think it's set 12a-12a which would explain the 30+ watts every midnight as it wakes up & then goes back to sleep.

jkirkebo & drees both suggest leaving a lower traction pack charge and setting a charge timer for a short time each day. Why do people think that will charge the 12v? Nothing I've read suggests the 12v is charged while connected other than the "every 5 days". My feeling is that the 12v is isolated when plugged in, so my theory is that it won't help. Has anyone actually left their leaf for longterm with this short daily charge?

As to why you can't use Carwings, you *can* get the kwh used. Unfortunately I've found it to be wildly low. Carwings only has about 1/3rd of the miles that I've actually driven. I spent several hundred dollars on The Energy Detective because carwings is so bad. Also, carwings can't detect low draws like the 30 watts/hr my charger was drawing while I suspect it was killing my 12v battery.

DaveinOlyWA makes a good point that if I had left it in any sort of powered on mode, the car would have drained the traction pack and required a charge. The Energy Detective records now seem even clearer proof that there's a bug in the 5-day timer where being plugged in prevents the 12v charge. My interpretation is that the small activity on my charger (30 watts/hr for 36 hours) after 5 days was the car stuck in a loop saying "wake up and charge the 12v", but then the car/charger saying "hey, the charger is plugged in, keep the battery isolated". So, ironically, it may be the 5 day timer and constant debate keeping the car awake that eventually killed the battery such that by the 7th day it couldn't even wake up at midnight for the 80% charge timer to kick in.

I don't support telling people to disconnect the battery, or trickle charge it. You are true EV supporters to go to such lengths, but I don't think that should be necessary and gives the leaf a bad reputation if that's what you have to do to keep it alive for 2 weeks. There's likely a bug and it needs to be fixed. My theory is you shouldn't have to do any of that if you keep the car unplugged. I'm very curious to hear back from jkirkebo if he can keep it plugged in and alive.

gonefishin said:

.... It's bad for everyone including us current owners if Nissan / EVSE manufacturers don't fix this aThnd a lot of leaf owners start having problems. Where there's smoke, there's fire...

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your post does bring to light a somewhat glaring oversight on 12 volt battery maintenance. but, i think the previous posts has motivated Nissan to provide fixes. the 2013 model has several enhancements which have been up to this point, vaguely alluded to.

better cabin climate controls, heating enhancements, etc. i can only assume that Nissan has altered what i am guessing to be a few dozen lines of code to allow the 12 volt battery to be maintained properly AT ALL TIMES provided a sufficient SOC is available from the traction battery.

in the 2+ years that i have been on this forum, a few things has become clear to me

1) the 2011 Leaf was a bit of a rush to market. it has issues but not enough to where i have regrets because i have ZERO. sure, it would be nice to get heated seats, more efficient heater and whatnot, but is it worth waiting an extra year...no, not even close

2)Nissan is listening and listening very carefully. there is little doubt in my mind that they monitor this and other sites to find out what is important to us and they are acting. each MY has had significant changes and its getting better all the time. this is not something that i see anywhere in the auto industry. a great example is the Ford Escape for 2013. lots of features that were very high on customer wish lists are here...after 6 years

I don't remember ... but what's the time-out on the CarWings when sitting for a long time ? Does an interaction with the CarWings put the car into an unintended state because CarWings is trying to communicate ?

The Volt has an as yet unsolved issue ... it is suspected that the Bluetooth module (cell phone) improperly shuts down, which then causes a drain on the 12V system, eventually causing a "dead" Volt. Does the CarWings "improperly" shut down ? Does the CarWings communicate while LEAF is plugged in and in OFF Mode ? Might the Bluetooth in the LEAF also contribute to the issue ?

Was your LEAF locked ?

gonefishin said:

jkirkebo & drees both suggest leaving a lower traction pack charge and setting a charge timer for a short time each day. Why do people think that will charge the 12v?

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Any time the HV battery is "engaged" meaning the car is Ready or charging, the car will charge the 12V battery if necessary. So if the car actually charges 20 minutes / week or so, that should be enough to keep the 12V battery topped off. Many suggest charging 20 minutes / 2x week or more if the situation allows it.

gonefishin said:

Nothing I've read suggests the 12v is charged while connected other than the "every 5 days". My feeling is that the 12v is isolated when plugged in, so my theory is that it won't help. Has anyone actually left their leaf for longterm with this short daily charge?

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Yes, people have done this - don't remember who.

gonefishin said:

I don't support telling people to disconnect the battery, or trickle charge it. You are true EV supporters to go to such lengths, but I don't think that should be necessary and gives the leaf a bad reputation if that's what you have to do to keep it alive for 2 weeks. There's likely a bug and it needs to be fixed. My theory is you shouldn't have to do any of that if you keep the car unplugged.

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As stated many times before - if unplugged the car will top off the 12v battery every 5 days automatically for you. The bug is that this doesn't seem to happen if the car is plugged in as it thinks it has topped off the 12v battery when it hasn't.

BTW - most manufacturers recommend disconnecting the 12V battery for long-term storage - where long-term is a period longer than 2 weeks. Draining 12V batteries is very common across all makes in storage.

Nissan LEAF Battery, Charging System: 12V Battery

My car is alive after a week at least. SOC is steadily increasing, and time to fully charge decreasing each day after the 20 minute charge.

It is my understanding that the 12v battery will be charged in the following circumstances:

- When the car is in READY mode
- When the car is left unplugged (every 5 days)
- When the car is plugged in and charging

It is my understanding that the 12v battery will NOT be charged if the car is plugged in and not charging (either because of a timer or if the battery is full or the breaker has popped).

So therefore I make sure that the car is charging for a few minutes every day. This should not only keep the 12v battery topped off, but also minimize the time spent at >70% SOC since it will use 14 days to go from 20% to 80% SOC.

gonefishin said:

Can someone actually say they've left their leaf OFF and plugged it in for 8+ days and had no problems?

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Yes I left mine off and plugged in almost three weeks last summer while visiting the UK.
No issues.

Although about halfway through the trip I was checking carwings and did inadvertantly start charging that of course continued to 100%.

@gonefishin: Just to complete the picture a little:
a) Are you still in Seattle area ?
b) What EVSE are you using ?

smkettner said:

Although about halfway through the trip I was checking carwings and did inadvertantly start charging that of course continued to 100%.

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Is there/should there be a "Stop Charging" button ? :idea:

When you guys say to set the timer for a 20 minute charge (if car left plugged in), are you referring to a normal (240v) or trickle charge? Or does it matter (assuming the full SOC stays below 80%)?

gonefishin said:

Can someone actually say they've left their leaf OFF and plugged it in for 8+ days and had no problems?

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Yes, I left my LEAF for 14 days with the 110V trickle charger plugged in in my garage. (BTW, that is what Nissan recommended I do). All was fine when I returned home. Each night the car charged back up to 80% in <5 min (if I remember correctly). The 12V battery was unaffected.

I will be leaving it for nearly a month in November of this year and plan to disconnect the 12V battery, but leave the car on the trickle charter again.