Battery Protection Limit

[RichMix]

Called that number - direct to call centre on the other side of the world.

No wonder theyve not heard of the issue

I tried to report but he couldnt understand

[Skku]

I called my Skoda dealer/garage and they said that they know of the problem and that they have reported it back to Skoda - but they haven't got any help from them so far...

[GT1]

So today all good on way to work - left unlocked for 6hrs with approx 6 openings of tailgate! Get in car to return home(7miles) & screen/speedo are blank!! The car does drive so set off for home still no screen/or audio but just the odd flash of lines across it! Approx halfway home it all sparks into life & everything appears okay except speedo screen shows all 4 doors open!!! Got home okay & locked doors with handle - went out again to shops & everything fine! Now at home & locked but have no idea what's going to happen tomorrow! I will be trying to ring Skoda Leicester tomorrow to find out wtf is going on!!

[MK09]

Well after getting the 12v battery low message and being unable to preheat the car on Wednesday, driving only 16 miles that day and the car being unused all of Thursday, I’m now able to preheat the car from the app this morning.

I’ve no idea what I’m going to get from this car from one day to the next.

[RichMix]

As above, mine isnt as bad today. I did notice last night (5pm ish) I had an error on app due to connection issue

"Apologies......

Unfortunately, we cannot complete your request right now. This situation is likely to be a temporary connection issue"

Every day is a challenge!

[CrowSysE243]

I have never received any notifications about 12V battery, nor about the battery protection limit being excceded, and cannot see any relevant notification settings in the MySkoda app that would relate to these, however recently I had a notification from the Octopus app that Octopus could not control the car which occurred when the first charge slot was due. On investigating in the MySkoda app I saw that the Battery Protection Limit problem. This was the first time since last winter. I unplugged and reconnected at the start of the standard off peak tariff period and Octopus smart charging completed successfully.

Since then I have been trying to induce the battery protection limit problem without success, however I did discover that the 12V battery is being charged while the HV battery is charging and also saw evidence suggesting that the 12V battery may also be charged at other times, even when the car is not connected to a charger. Today I finally managed to observe it, as well as a change in the behaviour of the MySkoda app, possibly related to the update to version 7.8.0 earlier this month.

The following screenshot shows the 12V battery current, 12V battery temperature and 12V battery state of charge from the time that I connected CarScanner to the time that I stopped collecting data.

At the beginning the battery is delivering about 15 A to the car systems as a result of being unlocked so that CarScanner could be connected without setting off the alarm. The car then relocked itself because the door had not been opened. The current gradually reduces to a steady value of about 2.3 A while the state of charge reduces from a reported value of 65% to 50%. It assume that it would be lower if CarScanner and the OBD2 Bluetooth dongle were not connected to record data. When it was near 50% I opened the MySkoda app for the first time today and observed that the app did not result in the car waking up and being shown as on-line. Previously this has happened after I accessed the app 3 times in a day without driving the car or 3 times since last driving the car. I then tried to wake the car by changing the target temperature. Previously this has always worked however this time I got a "Remote car control - near battery limit" screen, which I have not had before, and the target temperature change failed.

This appears to be equivalent to the "Battery Protection Limit" information previously seen and may be due to an app update.

Once the state of charge dropped below 50% the DC to DC converter starts taking power from HV battery and delivers approximately 20 A to the 12 V battery for a period eventually gradually reducing until the DC to DC converter switches off once the battery reaches 90% state of charge and the battery resumes delivering about 2.3 A. At this time the car woke up and was shown as on-line as soon as I accessed the MySkoda app.

The car completed OI smart charging to 80% 58 hours before the start of the recording. An hour later it was not possible to change the charging limit using the MySkoda app. The screen showed "Apologies... Unfortunately, we cannot complete your request right now. The situation is likely to be a temporary connection issue - please try again later." I have not had this before but assume that, as the 12V battery would have had a high state of charge at the time this is due to a server or data communiications problem rather than the "Battery protection limit". The 12V state of charge was 96%, which is more than the state of charge achieved during the test today, 3 hours after completing chargingnwhen the cable was disconnected. 96% is similar to the level previously observed immediately after charging. After disconnecting from the charger the car has not been moved. In a period of over 16 hours before the recording the reported state of charge reduced by 5% with no change in the reported total charge remaining constant. Some of this will have been as a result of unlocking the car both times to connect CarScanner.

From the tests so far it is clear that: for an iV80 with software version 3.5:
the car can charge the 12 V battery if the SoC drops to around 50%, achieving 90% in less than an hour.
The 12V battery is charged while the HV battery is charged. Charging from 75% to 95% takes about 30 minutes while AC charging at 7 kW.

The Vehicle wake-up limit for the app (3 per day for automatic wake up when the app is opened) does not prevent the car being woken up for remote control attempts.Changing a setting (car target charge or temperature) or starting/stopping charging is still possible. This does not adversely affect Intelligent Octopus smart charging.

It appears that when the 12V state of charge gets low Remote control is inhibited but recovers once the car has charged the 12V battery from the HV battery. This will affect Intelligent Octopus smart charging but it is likely that smart charging, but the significance is likely to vary.

I will have to think about how to investigate the behaviour further.

[Gd2]

Thanks for taking the time to research and post this CrowSys - very interesting.

Do you think a SoC reduction of 15% over a period of less than 2 hours is a normal? Assuming the car was sitting doing nothing at the time? It seems like a high rate of discharge to me?

In my case I fully charged the battery using a ctek charger and still had problems (certain functions not working like keyless entry, remote heating, interior lighting etc)

Lots of people experiencing the same problems suggest a software issue or a bunch of duff batteries all going bad at the same the due to the cold weather?

[riki1]

......
I will have to think about how to investigate the behaviour further.

Great, thanks for the comprehensive test !

[CrowSysE243]

Do you think a SoC reduction of 15% over a period of less than 2 hours is a normal? Assuming the car was sitting doing nothing at the time? It seems like a high rate of discharge to me?

The 15% reduction is high, however the car is not really sitting there doing nothing. I had CarScanner connected through the Bluetooth OBD2 dongle recording about 30 measurements per second so the car'ECU was at least moderately active. Most of the time the battery was delivering about 2.3 A so the car systems were using less than 30 watts, which does not seem unreasonable. I was a bit surprised that unlocking the car resulted in a high battery current for so long. It took about 5 minutes to reduce to about 2.3 A.

When I did not have CarScanner connected, but did still have the OBD2 dongle installed and powered, so the ECU did not have as much activity, the rate of reduction was much slower at 5% in over 16 hours. I do not know what it would have been if the dongle had not been in place and whether having Octopus smart charging enabled had an effect. These still need to be investigated.

I was also surprised that the car is reporting the 12V battery adapted capacity as 49 Ah, which is smaller than expected. Integrating the current draw over time as the SoC ran down suggests that approximately 4.5 Ah had been delivered which suggests a capacity of 30 Ah which is much lower than I expected. I will need to investigate these further as well.

For functions not to work after fully charging the 12V battery with an external charger suggests that there is something else wrong. I have never had a problem opening the car using the key fob. From the observed behaviour of my car I can see how there could be times when remote control using the app, or access for remote controlled charging by Octopus, etc, would fail however I would expect it to recover with the car using the HV battery to charge the 12V battery. It is possible that this does not happen if the HV SoC is low but there is some evidence from the historical data that I havesuggesting that the 12 V battery is being charged with the HV battery below 20% charge.

[Enyaqandy24]

I have done similar checks on our 85 (the issue is/was back yesterday)

After clearing the DTCs it definitely seems to help for a while when the weather was cold - it first reappeared when I got a notification on my phone about battery protection being active - at this point I was driving the car at 70MPH and there was absolutely no issue in the car. Without the app - there would have been no issue.

This made it clear to me that the notifications are at best delayed a reasonable amount.

It seems harder to record the data for extended periods in the 85 with 4.0 software. Leaving it unlocked uses more power it seems - but locking it or letting it lock itself after a period of being unlocked without being opened - always results in either the communication stopping or the alarm going off. Any tips CrowSysE243?

What I have noticed is that I have never seen a SOC below 85 - yet the notification is present - and the SOC doesn’t increase as rapidly (as it’s more charged already).

Some screenshots - with 12V battery temp varying between 3 and 9 degrees).

I’m starting to think a few different things…
1. Battery protection is actually the HV battery stopping itself from charging the 12V when the SOC drops and not a 12V issue directly - ie ‘the HV battery is cold and to extend range in the cold we are going to disable the 12V charging by reducing the 12v load’. This could also explain why charging the 12v directly appears to do nothing for GD2? This could be why it’s fine when the HV is charging also. Or

2. It’s a software issue in the car basing something on temperature only… or


3. It’s led from the servers… as in the cars are reporting temperatures and other properties back to Škoda - Škoda are then enabling this in the car intentionally - telling the car to go into this mode to stop the 12V going flat and saving millions in warranty costs. Or

4. A combination of all 3… Skoda are server side disabling the HV charging of the 12V to prevent 12V warranty issues, based on possibly incorrect temp data from the Škoda or predicted weather data at the location of the car.

I hope I’m wrong in this…

When it gets cold again it should be easy to test somewhat … Disable the data connection in the car - and see in the morning if the approach lights / touch sensors to unlock etc are working.

Either way… I’m predicting a software based issue and won’t be bothering with getting the 12V looked at.