2013 Leaf - Dead 12-Volt Battery every 2 Weeks

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LeftieBiker said:
Is it possible to either wire in a remote On/Off switch for the TC unit's power, or to relocate the power supply to a circuit that's only live when the car is on?
Click to expand...

That could possibly be done if one had access to the Leaf's wiring diagram. To start with, hopefully someone has taken
a picture of the location of the TCU and its electrical connector. Once that was done, obviously no CarWings access
remotely unless the Leaf was powered-up. But the same can be achieved until a viable update arrives by not accessing
the Leaf remotely via CarWings, which I presently do.
 
lorenfb said:
LeftieBiker said:
Is it possible to either wire in a remote On/Off switch for the TC unit's power, or to relocate the power supply to a circuit that's only live when the car is on?
Click to expand...

That could possibly be done if one had access to the Leaf's wiring diagram. To start with, hopefully someone has taken
a picture of the location of the TCU and its electrical connector. Once that was done, obviously no CarWings access
remotely unless the Leaf was powered-up. But the same can be achieved until a viable update arrives by not accessing
the Leaf remotely via CarWings, which I presently do.
Click to expand...
http://www.mynissanleaf.com/viewtopic.php?p=385507#p385507
http://www.mynissanleaf.com/viewtopic.php?p=148255#p148255

When I still had the 2G TCU and changed the cabin air filter by removing the whole glove box, I recall seeing a box (too bad I didn't take a pic) from Continental that had an IMEI (which made me suspect it was the TCU) and other numbers on it. I recall it looked like what Ingineer posted.
 
My thought was to wire in a remote power switch, turning the device off when the car would be sitting for more than a day, and leaving it on when the TCU was expected to be needed.
 
LeftieBiker said:
My thought was to wire in a remote power switch, turning the device off when the car would be sitting for more than a day, and leaving it on when the TCU was expected to be needed.
Click to expand...

If you are really concerned when the car will be parked for extended time, just pull the fuse that supplies power to the telematics control unit.
 
lorenfb said:
But the same can be achieved until a viable update arrives by not accessing
the Leaf remotely via CarWings, which I presently do.
Click to expand...

lorentfb,

Are you saying that while the car is sitting, if you don't try to ping it using CarWings things should be fine?

Thanks!
 
eddiebo924 said:
lorenfb said:
But the same can be achieved until a viable update arrives by not accessing
the Leaf remotely via CarWings, which I presently do.
Click to expand...

lorentfb,

Are you saying that while the car is sitting, if you don't try to ping it using CarWings things should be fine?

Thanks!
Click to expand...

Yes, for the last 6 months I haven't used CarWings and no problems, even when I update the charging stations.
Previously when using CarWings, the TCU would 'hang' requiring a reset by disconnecting its power via a fuse.
It's likely that if left in that mode, the TCU won't power-down causing excess current drain on the battery when the
Leaf is powered-off. Not only may the TCU cause an excess current drain, but it could 'keep-alive' a CAN bus,
resulting in potentially other ECUs from entering their 'sleep' mode (power-down) causing more current drain.
 
GerryAZ said:
LeftieBiker said:
My thought was to wire in a remote power switch, turning the device off when the car would be sitting for more than a day, and leaving it on when the TCU was expected to be needed.
Click to expand...

If you are really concerned when the car will be parked for extended time, just pull the fuse that supplies power to the telematics control unit.
Click to expand...

Not everyone would want to be pulling a fuse if they could flip a switch.
 
I wanted to confirm what some others have said about telematics causing a dead battery...

About a month after the TCU upgrade, my battery went dead. I bought a brand new battery. A month or so later, battery dead again. Brought it back to Batteries Plus and they said it had 5 amps! Charged it, dead again two days later. I remembered that both times the problem started after trying to access my 2013 Leaf via NissanConnect mobile app and getting a 'connection failed' message. After reading a few posts here, I decided to turn off all transmission/communications options in the car and NOT use my mobile app. No problems since then. I got a battery tender and mounted it under the hood. I plug it in once a week or so, just in case. Also got a portable jump starter that is very small and fits in the charging cable bag.

Schumacher SE-1-12S-CA Fully Automatic Onboard Battery Charger - 1.5 Amps
http://a.co/cQ4OYBf

DB Power 300 amp portable jump starter
http://a.co/2XH8qbJ
 
The TCU is it!
Just returned from our NorCal Nissan dealership, car was there for almost 5 days, while the team of technicians diagnosed the car and tried to find where the power drainage is coming from.
Today, i've found this thread with the information on the TCU and forwarded it to the service manager. they consulted with Nissan support line which suggested "Remove the TCU fuze from the car and check if the drainage goes down" lo and behold, the upgraded TCU was the root cause. Nissan service rep mentioned that during a conversation with the national service desk they were told that Nissan acknowledges the issue and there will be a recall for the upgraded TCU units for the 2013 model.

For those of you that are having the 12V battery drainage issue, use the following steps to disable the TCU from sending data to Nissan:
1. use the Zero Emissions button to the bottom right corner of the media console
2. go to Carwings
3. Settings menu
4. Using the right scroll bar, scroll all the way down to " Vehicle Data Transmission Setting" and tap on it.
5. select "Decline"

This will prevent the TCU from sending data to Nissan, the downside of it is that the mobile app(s) will not work as well.
The system will continue prompting to enable data transmission, just hit decline and move on.

Hope this helps others that might encounter the issue with 12V battery.
 
AP0LL0 said:
The TCU is it!
Just returned from our NorCal Nissan dealership, car was there for almost 5 days, while the team of technicians diagnosed the car and tried to find where the power drainage is coming from.
Today, i've found this thread with the information on the TCU and forwarded it to the service manager. they consulted with Nissan support line which suggested "Remove the TCU fuze from the car and check if the drainage goes down" lo and behold, the upgraded TCU was the root cause. Nissan service rep mentioned that during a conversation with the national service desk they were told that Nissan acknowledges the issue and there will be a recall for the upgraded TCU units for the 2013 model.

For those of you that are having the 12V battery drainage issue, use the following steps to disable the TCU from sending data to Nissan:
1. use the Zero Emissions button to the bottom right corner of the media console
2. go to Carwings
3. Settings menu
4. Using the right scroll bar, scroll all the way down to " Vehicle Data Transmission Setting" and tap on it.
5. select "Decline"

This will prevent the TCU from sending data to Nissan, the downside of it is that the mobile app(s) will not work as well.
The system will continue prompting to enable data transmission, just hit decline and move on.

Hope this helps others that might encounter the issue with 12V battery.
Click to expand...

Will try this. I upgraded my TCU in December and starting having issues in the Spring. Took it to the dealership and they said the battery was dead but in good health. I replaced my 12V battery at that time anyway which worked for 5 months and then died again in October. It died again last night so I purchased a charger, charging overnight. Car started fine this morning. Will turn off the Carwings setting later today.
 
I have a 2013 LEAF with the 3G TCU upgrade and am also experiencing the frequent 12V battery drain.
Has anyone heard of a successful resolution? E.g. replacing the TCU again and lucking onto a 3G unit that works? Or Nissan resolving the issue in some fashion (short of just disabling the 3G/TCU)? Does anyone have a 2013 with a 3G TCU that doesn't cause this 12V issue?

One day customer service tells me this is a known problem and to wait for an engineering solution and then next they say I should bring it into the dealership to troubleshoot and deny it's a known/broad issue. I'm confused.

P.S. My brother-in-law has a Model 3 reservation he's looking to unload. I'm seriously considering picking that up. But what resale value does a 2013 LEAF have with a malfunctioning TCU?
 
cmgolden said:
I have a 2013 LEAF with the 3G TCU upgrade and am also experiencing the frequent 12V battery drain.
Has anyone heard of a successful resolution? E.g. replacing the TCU again and lucking onto a 3G unit that works? Or Nissan resolving the issue in some fashion (short of just disabling the 3G/TCU)? Does anyone have a 2013 with a 3G TCU that doesn't cause this 12V issue?
Click to expand...
No. But, you could pull the fuse when the TCU seems to get stuck and stops communicating. That might help prevent the drain.

I do charge my 12 volt battery at least once a week with my Tecmate Optimate 4 charger so that help prevent the 12 volt from going flat. I think in the time I've had the (buggy) 3G TCU upgrade, I've only had 1 very low 12 volt voltage incident. My 3G TCU started working around May 2017 (http://www.mynissanleaf.com/viewtopic.php?p=494729#p494729). Let's just say I had a rocky start with it.
 
cwerdna said:
cmgolden said:
I have a 2013 LEAF with the 3G TCU upgrade and am also experiencing the frequent 12V battery drain.
Has anyone heard of a successful resolution? E.g. replacing the TCU again and lucking onto a 3G unit that works? Or Nissan resolving the issue in some fashion (short of just disabling the 3G/TCU)? Does anyone have a 2013 with a 3G TCU that doesn't cause this 12V issue?
Click to expand...
No. But, you could pull the fuse when the TCU seems to get stuck and stops communicating. That might help prevent the drain
Click to expand...

Or just stop using the TCU functions! I don't use it except for updating charging locations and NEVER have had any battery problems or a need to pull a fuse.
 
Just off of live chat with an EV rep after my 2013 needed a hard reboot and subsequent jumpstart:

The 12V battery drain concern is a known concern and Nissan is working on a fix. Unfortunately, until the patch has been released, all we can do is tell you to either jump start the vehicle when needed, or take the vehicle to the dealership and have them turn off the TCU until the fix has been implemented.
Click to expand...

He couldn't give me any reference number, but said I'd receive postal mail when there was a fix.

As a computer geek, I love that this is a "patch". We really are just driving computers with wheels these days.
 
"Jump start the vehicle when needed" is terrible advice. It's a recipe for a truly dead 12 volt battery in just weeks. You have to be more proactive than that.
 
LeftieBiker said:
"Jump start the vehicle when needed" is terrible advice. It's a recipe for a truly dead 12 volt battery in just weeks. You have to be more proactive than that.
Click to expand...

Yep, I've been tending my battery every other night. It's the only thing that saves me from having to jumpstart once a week. :-/
 
lorenfb said:
cwerdna said:
cmgolden said:
I have a 2013 LEAF with the 3G TCU upgrade and am also experiencing the frequent 12V battery drain.
Has anyone heard of a successful resolution? E.g. replacing the TCU again and lucking onto a 3G unit that works? Or Nissan resolving the issue in some fashion (short of just disabling the 3G/TCU)? Does anyone have a 2013 with a 3G TCU that doesn't cause this 12V issue?
Click to expand...
No. But, you could pull the fuse when the TCU seems to get stuck and stops communicating. That might help prevent the drain
Click to expand...

Or just stop using the TCU functions! I don't use it except for updating charging locations and NEVER have had any battery problems or a need to pull a fuse.
Click to expand...
Of course, I was hoping for a solution other than "just disabling the 3G/TCU." By analogy, if the using the heater caused the drive motor to stop, driving only during the summer (or wearing really warm clothes) is not the workaround I'd hope for from Nissan.
 
cmgolden said:
lorenfb said:
cwerdna said:
No. But, you could pull the fuse when the TCU seems to get stuck and stops communicating. That might help prevent the drain
Click to expand...

Or just stop using the TCU functions! I don't use it except for updating charging locations and NEVER have had any battery problems or a need to pull a fuse.
Click to expand...
Of course, I was hoping for a solution other than "just disabling the 3G/TCU." By analogy, if the using the heater caused the drive motor to stop, driving only during the summer (or wearing really warm clothes) is not the workaround I'd hope for from Nissan.
Click to expand...

As noted before, it's most likely a design problem only corrected by replacement TCU.
 
Reporting back a few weeks after a trip to the dealer. I handed them the verbatim quote:

http://mynissanleaf.com/viewtopic.php?p=513150&sid=166c909c9f2850bb1da6c7388ceed363#p513123

...and after a bit of fumbling ("Are you sure there's no bulletin ID?") they found the guy who knew what to do. Seems to have worked; I've been leaving it plugged in every night for weeks and no jump starts required.

It's been so nice not having to worry if my car is going to start when I get in it.
 
They replaced my 3G TCU with another. That was two weeks ago. No dead batteries yet, but they can't seem to get my TCU functions working again either. <sigh> Queue the clown music.
 

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