Is there a way to tell if a used leaf has had its TCU upgraded?

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backfield5560

Member
Joined
May 31, 2017
Messages
7
I'm in the market for a used Leaf (probably 2013). I looked at one today at Carmax, but passed for various reasons.

As I was checking it out I wasn't sure how to determine if the TCU has been upgraded. The GPS navigation seemed to work, but I don't think that has much (if anything) to do with 2g connectivity.

Is there a way to tell that the TCU has been upgraded?
 
Yeah I'm thinking of the scenario where I'm sitting in the car and messing with the display. Can I look at an icon that says whether the car is connected (assuming I'm at a location that should have connectivity)? I could install an app and try to connect it. There's not some info screen you can pull up which tells you that you're on the 3G network or which "version" of the TCU is installed?
 
The only thing I can think of is that if the car can still connect to Nissan, it's had the upgrade. Try asking the Nav screen to update the charging stations.
 
If the car will update charging stations, then it is connecting to the ATT cellular system. I don't know if ATT has completely discontinued 2G so connecting might not be a definitive answer. Since the upgrade is a dealer service, it should show in Nissan's records (and possibly in CarFax).
 
Here's the quote to save people time.


Relayer1956 wrote:

Here is the pertinent process (from the Nissan document) you can go through to check on your modem to see if it is 2G or 3G.

-----

NOTE: Vehicles without Navigation are ineligible as they are not equipped with TCUs.

Verify applicability using one of the following methods:
1. Check vehicle service history for previous repair (PC449 or PC450).
2. Check the TCU ID number on the vehicle information screen. If the TCU ID begins
with something other than 2012, it is a 3G TCU and does not require an update.
To identify if the vehicle has a 2G or a 3G TCU, complete the following steps on the
head unit:
3. Press the hard button labeled Menu.
4. Press the "CARWINGS" soft button on the center display screen.
5. Press the "CARWINGS Settings" soft button on the center display screen.
6. Select the down arrow on the center display screen.
7. Press "Unit ID information" soft button on the center display screen.
8. If TCUID starts with "2012-1" it is a 3G device.
9. If TCUID starts with "2012-0" it is a 2G device.

NOTE: As indicated above, TCU IDs that begin with something other than 2012 are 3G
TCUs and do not require an update.
 
Well my car arrived, and I looked at the TCU ID and it is a 2012-9xxxx

However when I tried to tell Carwings to update it says no service at my home location. So not sure if there just isn't cell coverage here for it to connect or if there is something else going on.
 
MalcolmReynolds said:
Well my car arrived, and I looked at the TCU ID and it is a 2012-9xxxx

However when I tried to tell Carwings to update it says no service at my home location. So not sure if there just isn't cell coverage here for it to connect or if there is something else going on.
I can't speak to that symptom, but if you want to be also to use the Nissan Connect app and the web site to check battery status and send commands remotely, you will need to get the account moved over to you from the previous driver.

You'll need to call EV support and they'll need proof that you now own the car. I had to go thru this when I bought my used Leaf in July 2015. This is all well before AT&T turned off their 2G network and was with the original TCU.

I think Carwings updating from the head unit side should work, but I'm not sure. The 3G TCU is also flaky and fraught w/problems anyway (for some? long story)...
 
cwerdna said:
MalcolmReynolds said:
Well my car arrived, and I looked at the TCU ID and it is a 2012-9xxxx

However when I tried to tell Carwings to update it says no service at my home location. So not sure if there just isn't cell coverage here for it to connect or if there is something else going on.
I can't speak to that symptom, but if you want to be also to use the Nissan Connect app and the web site to check battery status and send commands remotely, you will need to get the account moved over to you from the previous driver.

You'll need to call EV support and they'll proof that you now own the car. I had to go thru this when I bought my used Leaf in July 2015. This is all well before AT&T turned off their 2G network and was with the original TCU.

I think Carwings updating from the head unit side should work, but I'm not sure. The 3G TCU is also flaky and fraught w/problems anyway (for some? long story)...

Thanks for the reminder about the Nissan Connect account. I just tried to add the car and it is still linked to another account. So I will have to sort that all out some time this week when I have some time.
 
BTW, short summary (will need to write an update in the next few weeks) of my experience w/the $199 3G TCU update at http://www.mynissanleaf.com/viewtopic.php?p=497321#p497321.

The only flakiness the old 2G TCU had on my current Leaf and the leased one I had for 2 years was just associated w/(usually known) areas of no AT&T signal (e.g. inside certain underground parking garages or certain levels of them). I never had the problem where it'd be flaky for days in areas where there should be signal (I do also carry a phone on AT&T) nor DTC P3131 associated w/that yellow ! car light.
 
I managed to get the carwings/owners portal associated with my car, but they tell me that the TCU is still the 2g and that it needs to be upgraded.

So now the question is should I upgrade it given all the reported problems here with the new TCU draining batteries and other bad behavior? They told me that my car needs an airbag recall done so it is going in for that service. So I am wondering if I should have them do the TCU while there. Thoughts?
 
MalcolmReynolds said:
I managed to get the carwings/owners portal associated with my car, but they tell me that the TCU is still the 2g and that it needs to be upgraded.

So now the question is should I upgrade it given all the reported problems here with the new TCU draining batteries and other bad behavior? They told me that my car needs an airbag recall done so it is going in for that service. So I am wondering if I should have them do the TCU while there. Thoughts?

There are reports here of issues with the TCU upgrade, but what is missing are the reports from all those that had it done and have no issues. I had it done and have had only minor issues, after the initial install. The dealer did not follow all the steps to activate it, and it took Nissan EV Support seven weeks to get it activated in the system. After that, it has worked great. I have had to do a couple fuse pulls to reset it, but that is more an issue with still having the original battery in the car. The new TCU seems to be less tolerant of voltage drops and will go into a sleep mode if the battery voltage drops too low.
 
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