Disconnecting the 12v battery

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

hdcs

***
Joined
May 7, 2015
Messages
2
Hi All!

Looked around but didn't find a sign of this.If there's a discussion already on this, please point me at it.

So, I've had my e-Golf for a little less than a week and so far I love everything about it but Car-net, unsurprisingly. After waiting 72 hours for initial activation as the lady behind the I button recommended, I still had connection problems. On Tuesday, after reading the sketchy repots of OTA updates being triggered from the I button calls, I called hooey and tried a hail mary maneuver. I grabbed a wrench and disconnected the 12v battery just to see what would happen. Every other car I've owned has always been receptive to this hard reset and since this little beast is still a Golf, I figured why not try?

Initially, I was panicked on first start after reconnecting the 12v battery. The dash went nuts with failure errors about the TPMS, Hill Start Assist, Immediate service needed for the high voltage battery, and probably others I'm forgetting. However, after driving it a few hundred feet, everything was happy again. And lo and behold! Car-Net problems all went away! I could finally set options, configure charging locations and departure times, as well as actually successfully send commands with the Remote functions. And it's all working swimmingly.

Now, I haven't yet tried using delayed charging, nor have I gotten the update from VW that allegedly fixes the problems there. We've got two EVs now and only one 240v outlet and the Model S gets precedence on the 12:00 cheaper charge time. So the opportunities to try delayed charging haven't been there yet since I usually charge right when I get home. I'll give it a shot Friday night and see if I have the same troubles there everyone else has seen. And I'll likely go to my dealer next week for the new software if so.

But I was primarily curious if anyone's tried disconnecting the 12v as well. Seems like it might help, so I wanted to share.
 
Welcome!

I was just reading about this subject in the owner's manual last night and what you describe seems consistent with the expected behavior. Glad to hear it helped!

I had some connections problems after activating Car-net too, but they were able to initiate some sort of reset from their end that cleared it up.

The delayed charging issues are widespread, so we will need the TSB 2040470 fix. They really need to make the delayed charging a function of the car and not reliant on external services regardless.
 
I also had a problem initializing car-net. Dealer couldn't do it, so they called car-net. After an overnight stay at the dealership and several calls they had with car-net, it was suggested that they electrically disconnect car-net and turn it back on. That did the trick - so it seems there's a way to do what you did without disconnecting the entire car's electrical at the battery.
 
snAKes said:
They really need to make the delayed charging a function of the car and not reliant on external services regardless.
+100

Frank3 said:
I also had a problem initializing car-net. Dealer couldn't do it, so they called car-net. After an overnight stay at the dealership and several calls they had with car-net, it was suggested that they electrically disconnect car-net and turn it back on. That did the trick - so it seems there's a way to do what you did without disconnecting the entire car's electrical at the battery.
I have an appointment Monday for my dealer to work on this. They should be able to unplug or reset the box that communicates with Car-Net to clear the issue. I would try the 12V reset, but they should figure these things out themselves and not rely on owners to figure it out for them. I certainly hope that they don't keep my car overnight. I'm going to insist on a loaner if they do.
 
Totally agree on them needing to integrate these scheduling functions on the car. But I can see that being challenging as they're dependent on the infotainment system as an interface to it. Given that the software there is probably developed by a third party as a general part of all the VW ICE line up, my expectations are low that we'll see that anytime soon. Car-Net should be a free to very low cost option to all EV owners as long as we depend on it for this very fundamental item.

Also, my delayed charging schedule seems to be working right now! My previously config'd schedules are running right now and my app is correctly reporting status of the in progress charge. Let's see if it finishes properly!
 
Just wanted to jump in here and share that disconnecting the 12v battery worked for me as well. This had been my problem since day one. The person who activated carnet for me never said anything about a 72 hour initial activation period. Regardless, it never fully did whatever it's supposed to do because I could never really do anything in carnet. Just kept getting request unsuccessful. Disconnecting definitely did the trick. I already have the latest TSB to fix delayed charging, as the support folks I guess assumed that was the issue I was having. Boy did they sound surprised when I told them I still couldn't control the car through carnet, delayed charging or otherwise. As soon as I did this, the web app and mobile app both started working instead of throwing errors.

Thanks for the tip!
 
Getting the dealers acquainted with doing the Car-Net reset the way mentioned earlier in this thread (without disconnecting the 12v battery,) might be a good thing, if you have the time to take it in. Yeah, I know it's not our responsibility to educate the dealers, so maybe there's a (not very good but) better reason: I think I've read that a 12v disconnect reverts car preference settings (such as which doors are unlocked with the remote, etc.,) to factory defaults. Can someone confirm that?
 
jack8trades said:
I think I've read that a 12v disconnect reverts car preference settings (such as which doors are unlocked with the remote, etc.,) to factory defaults. Can someone confirm that?

Just ran outside to check. My door lock settings were not reset.

I do agree with the dealer thing. Although I have no problem getting under the hood, I realize that others may not feel the same way. It would be a good start getting the dealer and even more of the carnet support folks familiar with the symptoms to recognize this as something separate from the delayed charging issues as well.
 
After having me e-Golf for over 3 weeks and Car-Net basically useless, I decided to give this a try. After disconnecting and reconnecting the 12v battery, all functions seem to be working, although I haven't had a chance to try delayed charging yet. Before doing this, I could get the app to refresh lights & lock status, as well as parking location and current battery level, but climate control didn't work and no driving data was available. I also couldn't set and charging info in the e-manager. All is now functioning after the disconnect. All of my settings for door locks, etc. remained saved.
 
Hetz8500 said:
After having me e-Golf for over 3 weeks and Car-Net basically useless, I decided to give this a try. After disconnecting and reconnecting the 12v battery, all functions seem to be working, although I haven't had a chance to try delayed charging yet. Before doing this, I could get the app to refresh lights & lock status, as well as parking location and current battery level, but climate control didn't work and no driving data was available. I also couldn't set and charging info in the e-manager. All is now functioning after the disconnect. All of my settings for door locks, etc. remained saved.

Same for me. I did this yesterday. However, I was impatient on the re-boot and called Car-Net after a drive around the block and checking online (via browser, not the app) did not yet work. The Car-Net lady (all these folks are incredibly nice, btw) noted, "someone has recently rebooted your service," to which I responded, "oh, really, how strange." Then we tried the app and all was working well. Delayed charging not I've attempted yet, and likely won't as we are solar net-metering without timed rates.

Cheers,
Tim
 
+1

TSB failed to fix mine. Reboot two days later fixed it right up.
iPhone app had no control over car and even while charging showed as plug out.
Now it's working great
Able to add charging locations
Able to change schedule
Able to see and control charging status
None of this I could before reboot!

Good times
 
Yeah, the TSB and the Car-Net issues fixed by a reboot are really two separate issues. Car-Net support (and VW USA) really need to educate dealers how to fix this.
 
Has anyone checked out their 'Health report' after disconnecting the battery? Are the errors mentioned in earlier posts actually cleared?

Thanks!
 
My carnet doesn't show my current charge/battery status (shows not plugged in when its charging). Would the disconnect method work to fix that or do I need to go in for the TSB update?

If I did do the disconnect - how long are you guys leaving it disconnected? Like few seconds? Or a full minute? Longer?
 
Richie said:
My carnet doesn't show my current charge/battery status (shows not plugged in when its charging). Would the disconnect method work to fix that or do I need to go in for the TSB update?

If I did do the disconnect - how long are you guys leaving it disconnected? Like few seconds? Or a full minute? Longer?

I'm betting that a disconnect will fix this issue. When I did mine, I only left it disconnected for about 5-10 seconds. The dashboard will light up with warning lights once you reconnect it and start it up for the first time, but drive it for a little bit and they'll all turn off. Car-net was also fully functioning within about 5-10 minutes after I did this.
 
I'm still having issues from my phone. I'm able to access car-net from my PC but not my phone(HTC One M8). Anyone else able to successfully access car-net from an HTC One M8?
 
Took my car into the dealer last week and had the update applied. Still did not resolve the issue.

I have a case opened with VW and a regional case manager is looking into it. I haven't reset the car yet as I am curious to see what the troubleshooting steps will be moving forward. If I get impatient I will give the reset a go.

I will keep you posted as I hear more.
 
Richie said:
My carnet doesn't show my current charge/battery status (shows not plugged in when its charging). Would the disconnect method work to fix that or do I need to go in for the TSB update?

If I did do the disconnect - how long are you guys leaving it disconnected? Like few seconds? Or a full minute? Longer?

Hmmm, for some reason - carnet started to show charging status. I didn't even do the disconnect battery trick on it... did they do something to Car-Net on the server side recently? I did not make any changes locally - the app on my phone / webapp just started showing the charging status properly.

I have not tried delayed charging since I don't really need that function.
 
cdGolf said:
Has anyone checked out their 'Health report' after disconnecting the battery? Are the errors mentioned in earlier posts actually cleared?

Thanks!

Yes, my health report came back all green check marks today. I did the dirty deed (12V disconnect) a few days ago. Everything's good now but I couldn't use my cruise control during the first drive. It worked on the second drive though.
 
I've had my eGolf for a little under a month now, and the only way to get Car Net to work was to disconnect the 12v battery like all of you had. All went exactly as described here, with the exception of all my previous driving data was lost. Also now when I request a health report there are errors that weren't there before. I get a yellow error on:
Driver Assistance Systems
Hill Hold
Electric System
Hybrid Components
Tires and Brakes
Electronic Stability Control (ESC)
Tire Pressure Monitoring System (TPMS)
Tire Pressure Monitoring System (TPMS)

When I first started the car after disconnecting the battery all the warning lights went off on the dash, but quickly reset themselves. I drove the car for a while, then charged it up, and drove it later in the evening. Seemed fine, but did roll back on hills now.

I'm going to give it a few days to see how it plays out but if the errors are still there in a few days I will take it back to the dealership. Anyone else have this happen to them?

All of Car Net works now, so thats nice. : )
 
Back
Top