12v battery being drained by charging station

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bloch

***
Joined
Apr 30, 2018
Messages
1
Hi,

Based in Netherlands and driving a new VW eGolf 2017. In the last 4 months, the starter battery has died 4 times, meaning i've needed to get a recovery vehicle to recharge. The car dealer has replaced the starter battery already once, but after the last time it died last week, they're now claiming the issue is not the car but the charging station - they're saying it is draining the starter battery whilst charging the car overall.

Logically it doesn't make sense to me, it sounds like an architecture flaw in the car, rather than the charging station - has anyone else experience similar issues? Any suggestions? In the Netherlands, we have tons of public charging stations that you use and typically you leave the car overnight. I dont like the thought of every time i charge worrying if it'll be ready to go the following day so if anyone has any thoughts on how to approach, would be really appreciated.

Thanks,
Bobby
 
bloch said:
Hi,

Based in Netherlands and driving a new VW eGolf 2017. In the last 4 months, the starter battery has died 4 times, meaning i've needed to get a recovery vehicle to recharge. The car dealer has replaced the starter battery already once, but after the last time it died last week, they're now claiming the issue is not the car but the charging station - they're saying it is draining the starter battery whilst charging the car overall.

Logically it doesn't make sense to me, it sounds like an architecture flaw in the car, rather than the charging station - has anyone else experience similar issues? Any suggestions? In the Netherlands, we have tons of public charging stations that you use and typically you leave the car overnight. I dont like the thought of every time i charge worrying if it'll be ready to go the following day so if anyone has any thoughts on how to approach, would be really appreciated.

Thanks,
Bobby

Almost sounds like you are leaving something electrical turned on, on in the car,while parked, a vampire load. Turn off all ancillary electrical draw devices before you turn the whole car off, every time, and see if that removes the problem.

Short of that, it sounds like the lipo battery is not recharging your 12v battery and that's a function of the electrical charging box in the engine compartment with all the orange electric heavy duty wire going to it being broken. Chargng stations don't drain your battery, they can only add a charge. That's a nonsensical excuse, and complete VW dealership bull shit.

Recharge at home and see if the problem goes away.

This is a perfect example of your government public infrastructure failing. These are not overnight public parking spots, they are public recharging /refueling stations. Move your car when it's finished refueling. BTW, i am American / Dutch... Kees van Vliet.
 
This sounds like a defect in the DC-DC converter. This is the part of the electrical system that charges the 12V battery from the high voltage traction battery. Whenever the traction battery is connected to the car, like when the car is being driven or being charged, the DC-DC converter should be charging the 12V battery. This is easy to verify. All you need to do is put a volt meter on the 12V battery while it's charging and while the car is turned on and showing Ready on the dash. A voltage between 13.5V and 14.5V is charging the battery. You can also check the resting voltage when the car is turned off for more than 10 minutes. A good 12V battery should be around 12.7V when resting.

It is impossible for a charging station to drain the 12V battery if the car is working properly. Even an accessory load cannot drain the battery while charging if the DC-DC is working properly. However, after charging finishes, the accessory load like a dome light could drain the 12V.
 
Hello from the uk.

My new e-Golf V7.5 complete with heat pump at £830 is just 13 days old and had this very problem today, this is our 3rd EV, we also owned an e-Up, and now have a V7 e-Golf to match the new toy, all from the VW stable.

Last night we went to a charging station and charged the car on a DC 44Kw charging station then we drove home arriving about 23:00, we topped it up with our 7Kw home charging unit and left it cooking over night.
Today I went to the car at 11:45am to go out, I had a bit of difficulty removing the charging plug but eventually managed to do so and then heard a warning sound and saw an error message on the screen, and then another, and another, I took out my phone and started taking pics and video’s as the car encountered an epileptic fit. A few phone calls later and VW Asistance is sending an engineer to the house, he didn’t arrive until 18:40 and was here for about an hour, he tested the battery and said your 12v battery is showing 2v (two volts) quite how a 12v battery gets down to 2v I don’t know, anyway it’s now on charge and is almost back to 12.5v in a resting state, we will reconnect it in the morning and see if it starts. The engineer said something must be draining the battery but the only things that are connected to the car use the trunk and centre console 12v sockets, nothing extra has been fitted to the car that wasn’t installed at the factory.

I also contacted the dealer on the 13th day (today) to advise them of the situation and to notify them that I may reject the goods within the 14 day cooling off period, applicable under uk law as part of the distance selling rules and regulations should it come to that.

Tomorrow I will go to the local dealer to see about a new battery and to ask them if it’s fit for use.
 
I would imagine either something is draining the battery, or it's not being charged properly or the battery itself is defective. I think the easiest test is to swap in a new 12V battery. Also, I would imagine the dealer can test the DC-DC converter to see if it's working properly. Good luck!
 
Hi Everyone,

Is there any logical explanation from VW dealers or authorized service for e-Golf 12V battery drain issue? We have also faced similar problem and wanna learn the root cause not to see this again.

Thanks for your help.
 
gorkemozvural said:
Hi Everyone,

Is there any logical explanation from VW dealers or authorized service for e-Golf 12V battery drain issue? We have also faced similar problem and wanna learn the root cause not to see this again.

Thanks for your help.

A short somewhere in the wiring, pinched or chafed, or a stuck electrical relay, is my guess. Take it back to the dealership you bought it at and let them troubleshoot.
 
I'm also based in the Netherlands and I'm also facing the same problem! My 12V battery drains when I'm using public charging stations based in the Amsterdam area. My dealer blames the charging stations as well but I just will not except this argument for other EV's like Teslas charge without issues. The strange thing is that the 12V battery does not drain when I'm charging at any other charging station or when the car is not connected at all.

Does anyone have a solution yet?

Kind regards,
 
Fitzgerold said:
I'm also based in the Netherlands and I'm also facing the same problem! My 12V battery drains when I'm using public charging stations based in the Amsterdam area. My dealer blames the charging stations as well but I just will not except this argument for other EV's like Teslas charge without issues. The strange thing is that the 12V battery does not drain when I'm charging at any other charging station or when the car is not connected at all.

Does anyone have a solution yet?

Kind regards,
It should be impossible to drain the 12V while charging. The DC-DC converter should be powering the car and charging the 12V battery. Something is definitely wrong with your car.
 
This issue is caused by the EVBox charger. (I assume you are using a EVBox charger). A firmware upgrade of the charger should do the job.

The issue is in the communication between the car and the charger.
 
Hi, I am facing the same problem with an EV-BOX + E-golf.
any developments/solutions on this issue?
 
Here is a quick test.

By default the 12V "cigarette lighter" sockets go OFF with the ignition.
There are two of them... the other is in the trunk, right side, high up, IIRC.

But you can move a fuse and override this behavior.

Has your fuse been moved to change the default OFF with ignition behavior?

Barry
 
BarryMW said:
Here is a quick test.

By default the 12V "cigarette lighter" sockets go OFF with the ignition.
There are two of them... the other is in the trunk, right side, high up, IIRC.

But you can move a fuse and override this behavior.

Has your fuse been moved to change the default OFF with ignition behavior?

Barry

What exactly does this test mean regarding my problem?
Just checked: In my car the described 'default' is true.
Any other ideas solutions?
 
In my case it turned out that the charging point itself(evbox) contained a software bug. After it was updated, no more issues appeared. This might be the case for other evboxes in the Amsterdam area.
 
Fitzgerold said:
In my case it turned out that the charging point itself(evbox) contained a software bug. After it was updated, no more issues appeared. This might be the case for other evboxes in the Amsterdam area.

Do you have any document/mail about this and/or laadpaalnumber?
 
Fitzgerold said:
In my case it turned out that the charging point itself(evbox) contained a software bug. After it was updated, no more issues appeared. This might be the case for other evboxes in the Amsterdam area.

Evbox has uploaded a new firmware in the charger point and it seems the problem is solved.
It took a while but after they seriously looked at the problem the solution came quick.
Now I am live-testing the next days/weeks.
 
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