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Failed charge controler during BMS update. (Retitled)

Why have you change the thread title, someone been speaking with you?
Yes - but the old title did get the car looked at friday afternoon as a priority from the dealer in question, so renamed the thead as they been nice. But still not a resolved issue until I can get the battery closer to 455v when 100%.

I'm planning on going to the furthest Tesco I can legally can on monday morning, and doing everthing they say to do not do in the eco driving manual so get the lowest miles/kw I can achieve to get the most electricity out of the battery to try to rebalance it again.
 
Yes - but the old title did get the car looked at friday afternoon as a priority from the dealer in question, so renamed the thead as they been nice. But still not a resolved issue until I can get the battery closer to 455v when 100%.

I'm planning on going to the furthest Tesco I can legally can on monday morning, and doing everthing they say to do not do in the eco driving manual so get the lowest miles/kw I can achieve to get the most electricity out of the battery to try to rebalance it again.
Seems like a plan.
Quick reaction from the dealer though, just shows you they scan the blogs/used groups.
 
Had the latest BMS software applied to my first registered 6th January 20 ZS EV on 20th January 2021.
The dealer applied this update after I had asked them to apply the HV fuse protection update ( SA017 ).
They also did the wiring harness recall on the drivers door and the first service.
After carrying out this work, they where unable to boot up the car.
It was completely dead !.
After uploading the data package to MG tech, it was discovered from the info collected by the car, that it had detected a possible theft and sounded the alarm and disabled the car !.
Stuck on the ramp with the handbrake firmly applied.
The car responded to the spare key that I brought from home.
When I collected the car, I was told it was fully charged the previous night.
How long that charge had taken to balance the pack, I have no idea.
On boot up in the default "N" mode, the range was given as 162 miles and the voltage on the pack was 450 volts.
Not the magic 455 volts, but I am truly hoping that this will improve after a couple of cycles on my home wall box.
Under current conditions of lock down, it is impossible to consume the range and then attempt a full charge and balance process, so god knows how long THAT is going to take !.
More than a little annoying, as the car had NO issues prior to being submitted for it's first service etc.
We offer up out cars to these people who should be able to perform these simple tasks.
The items I had done, when recommended by MG themselves.
They are required to comply with the T&C's of the warranty, the very thing that is there to protect our cars.
Look where that got me !.
Now I have the worry that my car can perform the same as it did PRIOR to taking it in for the work !.
 
Hi. 162miles range showing after 12 months and in the winter is very good. all batteries degrade over time - yours looks minimal. These things can happen - they sorted it for you in the end. just enjoy your car. If you have issues then book it back in to be sorted. 7 Year warranty 🙂
 
Perhaps Mg have lowered the full charge voltage to 450v in order to speed up the balance charge, but allowed it to go 5v lower into the bottom buffer end of the battery, resulting in the same actual usable capacity? I have the old BMS which chargers to 455v and I am going to run the battery down to the point where the charge HV light comes on and make a note if the voltage at that point. Maybe someone who's had the latest BMS update could do the same and look at the voltage at the exact time the light comes on. My car is due it's first service in a few weeks but I won't want them to do the BMS update if they're taking away some of my useable range.
 
Perhaps Mg have lowered the full charge voltage to 450v in order to speed up the balance charge, but allowed it to go 5v lower into the bottom buffer end of the battery, resulting in the same actual usable capacity?
From what I hear, you should have 455 volts after a full charge after the latest update IF.
You have fully charged the battery to 100% AND you have done this about 4 to 6 times.
After this, you SHOULD be back to normal.
The car reporting 430 - 430 volts after a charge that had taken hours to balance the battery, is a fairly good sign that you have the "Buggy" BMS software.
 
Yes - but the old title did get the car looked at friday afternoon as a priority from the dealer in question, so renamed the thead as they been nice. But still not a resolved issue until I can get the battery closer to 455v when 100%.

I'm planning on going to the furthest Tesco I can legally can on monday morning, and doing everthing they say to do not do in the eco driving manual so get the lowest miles/kw I can achieve to get the most electricity out of the battery to try to rebalance it again.
Did you manage to do this? Have you tried rebalancing it again?
 
Finished rebalanced last night - 449v. No improvement since last time. But havnt got worse. Cant do any more test for time being.
Took 5 hours to balance.
The question is, has MG lowered the top voltage in this BMS update?
 
Hi All,
Please are these statements true or false?
Just will like to know what we all understand about balancing and the state general of the MG Dealerships
1. MG ZS EV and most EVs in general are designed to do a balancing charges only after a specific number of non- balancing charges (15-25) or during a recharge that follows a nearly complete or full discharge of the HVB.
2. If the battery is connected to power supply and charges to full but the BMS analyser controls do not indicate a balancing charge is required then a balancing charge will not occur no matter how long the EV remains connected to a power source
3. Balancing is subject to all the same physical and material limitations of any battery so temperature and several other factors will affect the power load and voltage and it will be impossible to always achieve one fix voltage after a very single balancing charge.
4. MG ZS EV HVB fuse update relates to high voltage DC charger protection for the MG BMS and HVB and in principle has little to do with balancing charging.
5. While acknowledging the very very poor level of EV knowledge and service at some of the GM dealerships, the average EV user also has very limited knowledge of the technology that goes into running of EVs. We therefore are completely at the mercy of the manufacturer. The dealerships like us are all learning about EVs so customer and dealerships should support eachother and have confidence that the manufacturer will not deliberately put systems into the EV that will but us at risk and that should anything be discovered that puts us at risk it will be promptly corrected.

So which of the above statements are true or false for you?
 
Finished rebalanced last night - 449v. No improvement since last time. But havnt got worse. Cant do any more test for time being.
Took 5 hours to balance.
The question is, has MG lowered the top voltage in this BMS update?
What would be the reasoning for them to lower the top voltage?
 
Hi All,
Please are these statements true or false?
Just will like to know what we all understand about balancing and the state general of the MG Dealerships
1. MG ZS EV and most EVs in general are designed to do a balancing charges only after a specific number of non- balancing charges (15-25) or during a recharge that follows a nearly complete or full discharge of the HVB.
2. If the battery is connected to power supply and charges to full but the BMS analyser controls do not indicate a balancing charge is required then a balancing charge will not occur no matter how long the EV remains connected to a power source
3. Balancing is subject to all the same physical and material limitations of any battery so temperature and several other factors will affect the power load and voltage and it will be impossible to always achieve one fix voltage after a very single balancing charge.
4. MG ZS EV HVB fuse update relates to high voltage DC charger protection for the MG BMS and HVB and in principle has little to do with balancing charging.
5. While acknowledging the very very poor level of EV knowledge and service at some of the GM dealerships, the average EV user also has very limited knowledge of the technology that goes into running of EVs. We therefore are completely at the mercy of the manufacturer. The dealerships like us are all learning about EVs so customer and dealerships should support eachother and have confidence that the manufacturer will not deliberately put systems into the EV that will but us at risk and that should anything be discovered that puts us at risk it will be promptly corrected.

So which of the above statements are true or false for you?
I think that you make some very good points. The whole BMS thing has developed into an intoxicating mix of variants and opinions. For example my car;
1/takes a timed charge (setting wall box to switch on at a particular time with cable plugged in and car locked starts charging).
2/it won’t AC charge when unlocked 3/it has the ‘comfort2’ update that shows range and outside temperature.
3/a full charge shows 455v But, I’m told it needs the latest Jan21 BMS update?
I have always been of the opinion with software that it’s almost always better to be on the latest update - however, with obtuse and overly complex versioning and no definitive software version numbers to work to, that I can see, this becomes almost impossible to track and manage. No wonder dealers are struggling. If for example MG were able to say the latest update was version 2021.1.0 then we could all work to a benchmark. This feels like a transition period to a software era that is still in it’s infancy. For example whilst Tesla are by no means perfect - they are predominately a software company making cars. Totally different from a car company trying to produce software.
 
I find it odd that they’re not on top of this. The car has been out for over a year and they still don’t have a handle on these updates.

Surely it’s up to each individual garage that has had a Zs Ev in and had an update to keep a record of which one. Then, they should contact each owner to advise them that an update is needed ONCE it’s clear it works, not use the owners as some sort of beta testers for their systems.
 
I find it odd that they’re not on top of this. The car has been out for over a year and they still don’t have a handle on these updates.

Surely it’s up to each individual garage that has had a Zs Ev in and had an update to keep a record of which one. Then, they should contact each owner to advise them that an update is needed ONCE it’s clear it works, not use the owners as some sort of beta testers for their systems.
I agree in part but how is the software to be tested in real life if not with owners? Just reading through the threads on here there are so many different situations and combinations that cannot be tested on paper and need to applied to see how they impact on these. It's not like they are starting with everyone in the same situation.
I'm not desperate for the latest update as hardly doing any miles at the moment so I am grateful for the Beta testers sorting it. :)
 
I find it odd that they’re not on top of this. The car has been out for over a year and they still don’t have a handle on these updates.

Surely it’s up to each individual garage that has had a Zs Ev in and had an update to keep a record of which one. Then, they should contact each owner to advise them that an update is needed ONCE it’s clear it works, not use the owners as some sort of beta testers for their systems.
You'd think that with MG using a digital service record system, it shouldn't be too much of a stretch to have that sort of info recorded during the update.
 
I think that you make some very good points. The whole BMS thing has developed into an intoxicating mix of variants and opinions. For example my car;
1/takes a timed charge (setting wall box to switch on at a particular time with cable plugged in and car locked starts charging).
2/it won’t AC charge when unlocked 3/it has the ‘comfort2’ update that shows range and outside temperature.
3/a full charge shows 455v But, I’m told it needs the latest Jan21 BMS update?
I have always been of the opinion with software that it’s almost always better to be on the latest update - however, with obtuse and overly complex versioning and no definitive software version numbers to work to, that I can see, this becomes almost impossible to track and manage. No wonder dealers are struggling. If for example MG were able to say the latest update was version 2021.1.0 then we could all work to a benchmark. This feels like a transition period to a software era that is still in it’s infancy. For example whilst Tesla are by no means perfect - they are predominately a software company making cars. Totally different from a car company trying to produce software.
It’s a complete mess to be honest.
If you are receiving 455 volts after a full charge and the balancing process is not taking hours, then stick with your current software package !.
What ever number they want to call it !.
Having the latest software package and getting it installed correctly is two different things !.
 
linked to the vin number....cant go wrong then.
MG have a system all linked to VIN. I believe it is called the dealership Bulletin or something similar name. It has all the updates and the update numbers and which VIN numbers need which updates. Unfortunately several dealerships seem unable to use this system properly. Except for Chorley Group dealerships which seem to have a 100% correct interphase the general impression here in the UK is that the dealerships just are unable to use the system. I do not know why.
For example it seems some dealerships instead of requesting which VIN require an update will load up which VIN have already had an update. When one turns up for an update the dealership not knowing what VIN they have mean will inform the customer their VIN is not on the list so the update will not be done when actually the customer's VIN not being on the list means they require the update.
Another common example is use of wrong search term.
For example in early 2020 some customers were laughed at and turned away at certain dealerships when they went asking for delayed charging. This was because the correct name of the update was BMS update and because the dealership staff did not know or understand that it was BMS update that was required for delayed charging they will search for delayed charging on the system and find nothing. The correct search should have been BMS update as a search for delayed charging will not bring up any appropriate result on the MG system. Again Chorley Group dealerships because of their vast experience with selling the Leaf were one of the few dealerships that correctly dealt with this issue.
MG plan to expand their dealerships network in the UK this year but it is abundantly clear that better training of Dealership staff is required.
 
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