Recent BMS update

[WalkingBootWeather]

A few points:
I have sat in the car with the radio on whilst it charged on a rapid charger with doors unlocked, and I have not had a recent BMS update.......
My car is a year old, 5500 miles, and I did have the first BMS update which allows the external temp display etc. t the first annual service last week, I instructed no new BMS update as I am quite happy with how the car performs.
However, I would be interested to know if any members think there are advantages to having a recent update?

I think you may be confusing a few different things Tim.. The ZS has always allowed rapid charging (DC) with doors unlocked. The ability to charge on AC (granny or fast charger) was originally only possible when the car was locked, and stopped as soon as you unlocked the car. The ability to charge on AC when locked was introduced as part or one of the BMS updates.

Changing the display to show the external temp came as part of the comfort 2 upgrade which also 'de-bonged' the car.

If you are running an early BMS version the car will likely 'go to sleep' and you won't be able to 'wake it up' if you want to use timed charging. If you have the summer 2020 BMS update you will probably get timed charging but the car will take ages to balance. If you have the late Oct 2020 BMS update the battery won't balance properly at all.

As far as we can tell the Jan 2021 allows charging on AC when car is unlocked, allows timed charging, and balances the battery properly. I'm still seeing long balancing times but maybe my battery is not back in balance yet, and this will settle down.

If you have an early BMS version, your car is performing well and you are not bothered about timed charges or stopping charging on AC when you unlock stick with what you have got.

 

[WalkingBootWeather]

Other EV car manufacturers don’t show voltage like we see on our MGs so I think we have more info than we need here

True, but many EVs do show the power that is going in or being drawn (volts x amps), and generally they also show state of charge. I'd be happy not to see voltage if I could see power and SoC.

 

[Richie]

Last night I did yet another equalisation charge.
Same voltage, 449.25V, but the imbalance is now down to 20mV. The equalisation charge took 8 hours. It started at 89%, so that bit took under an hour!

the longer you can leave the equalisation the better. And my battery is probably almost as close to ‘normal’ as it’s going to get! Though I will try a few more equalisation charges.

Just to add my little observation for equalisation.
We had BMS update Oct 14th and Dec 1st then again late Jan for latest one. Not too many trips so not much charging been done but never got more that 403v per charge. Yesterday I did two 32 mile round trips and managed 3.4 & 3.6 m/kw. Its now 06.05 and the cars been on charge for 12hrs 25mins, initial SOC was 11% and 17 Miles now added 79% with 122 miles. EV charge rate now is 1A/230W showing on the app at 90% and 104 miles. Will leave it charging to see how long it will take to complete. Am I to expect it to show 100% and still go on to equalise (pulsing light) or should that be it? I'll check the V's when I get up

 

[Lovemyev]

Am I to expect it to show 100% and still go on to equalise (pulsing light) or should that be it? I'll check the V's when I get up

The MG logo will pulse slowly unit the car reaches 100% SOC fully charged, then the MG logo will change to a constant glow.
This is when the “Balance” process has commenced.
Your green charge light on your wall box will still be ON.
Don’t be tempted disconnect the cable because it is still pulling a very small amount of juice.
When completely finished, the car will stop the charge and the light on the wall box will change to the blue colour.
Now your complete !.
My first charge / balance from a starting point of 92% SOC - took over 11 hours !,

 

[Trevor]

I think you may be confusing a few different things Tim.. The ZS has always allowed rapid charging (DC) with doors unlocked. The ability to charge on AC (granny or fast charger) was originally only possible when the car was locked, and stopped as soon as you unlocked the car. The ability to charge on AC when locked was introduced as part or one of the BMS updates.

Changing the display to show the external temp came as part of the comfort 2 upgrade which also 'de-bonged' the car.

If you are running an early BMS version the car will likely 'go to sleep' and you won't be able to 'wake it up' if you want to use timed charging. If you have the summer 2020 BMS update you will probably get timed charging but the car will take ages to balance. If you have the late Oct 2020 BMS update the battery won't balance properly at all.

As far as we can tell the Jan 2021 allows charging on AC when car is unlocked, allows timed charging, and balances the battery properly. I'm still seeing long balancing times but maybe my battery is not back in balance yet, and this will settle down.

If you have an early BMS version, your car is performing well and you are not bothered about timed charges or stopping charging on AC when you unlock stick with what you have got.

Not all correct with what you're saying either WalkingBootWeather.... Rapid charging (DC) could not always be done with doors unlocked. At ecotricity I could connect up and get in car, lock doors and start charge from App, but there were a few occasions when I roamed the neighbourhood as I needed to lock the car before pressing the start button on the charger. Unlocked DC charging is great as you can now sit in car with heater on whilst charging (I'm assuming this is safe to do?).

Also, there is a separate update to comfort 2 that puts outside temperature on the display. I received this when having the wiring harness changed. It did not change the bongs.

 

[WalkingBootWeather]

Apologies and I stand corrected if I'm wrong @Trevor. I had been watching these threads pretty closely and hadn't seen any other reports that charging stopped on DC with doors unlocked (and which update fixed this) ,or that anyone had got temp display other than as one part of the Comfort 2 update. I do understand that the Comfort 2 update did comprise a number of steps and applying separate updates, so theoretically some just functionality could be delivered, I'd just not heard on anyone that had only got the temp display without the de-bonging.

I'm sure others will be along shortly to confirm if their cars behave the same as yours.

It does raise some support issues though if we are all running different versions of software and have cars that function slightly differently. Much easier if dealer applies latest software updates as part of the service so that all cars behave the same and benefit from improvements. (making the rather large assumption that each update is an improvement on the previous version)

 

[Cocijo]

Yes - the errors in application of software, it’s fragmented nature as well as poor versioning and no customer release notes do tend to add up!

 

[Richie]

The MG logo will pulse slowly unit the car reaches 100% SOC fully charged, then the MG logo will change to a constant glow.
This is when the “Balance” process has commenced.
Your green charge light on your wall box will still be ON.
Don’t be tempted disconnect the cable because it is still pulling a very small amount of juice.
When completely finished, the car will stop the charge and the light on the wall box will change to the blue colour.
Now your complete !.
My first charge / balance from a starting point of 92% SOC - took over 11 hours !,

Thank you.
Its now 10.27am and the app is still pulsing and now showing 91% 142 miles with Ev charge rate of 0.
Wifie, said the badge is not on (she might be blind?) Opened the door and heard the power disconnect and the dash said 100% and 163 miles. Door shut, power back on and now at 10.35 the app shows 92% 142 miles with an EV charge rate of 2A/230W. Plug in time of 16hrs 55mins.
Edit
11.12am app now shows 0A/0W wall box green, badge is off and now I'm off!

 

[Tim Green]

I have had no issues with charging or mileage, but then I only use the granny charger, apart form on long trips. I usually charge overnight and then with everything turned off and on Eco it shows 203 miles. What makes you think I have a defective BMS? If you have the "EV only blue" and live in Bicester I have probably seen your car around! (Same colour as me)

 

[Tim Green]

On a more important note, MG really need to get a grip with their software releases and updates. They are obviously not documented or tested properly and this will ruin the MG reputation if they are not careful. In days of yore, As an engineer, I used to work in the motor industry (Smiths Industries) and any change needed at least 6 months of testing and approval before going "live". In general, I am pleased with the car and use it most days. I think we should be pressuring the Government to insist that every filling station has at least one fast charger - I cannot understand why that has not happened.

 

[Cocijo]

We are now in the age of Agile software development and release. Some manufacturers need a complete rethink of their approach and overall customer strategy, In order to bring it in line with best practices.

 

[jamesie]

There are definitely different versions and possibly part implementations of revisions on MG cars.

I bought my ZS EV on 23 November 2020. The dealer assured me that all the software modules had been updated. Sure enough the Comfort 2 had been done and I can AC charge with the car locked or unlocked and delayed charging is OK.

So, my deduction is that I should have the bad BMS module released on 24 Oct 2020. However, I have no symptoms - at full charge the car shows 455 volts with GOM showing 173 miles (Eco), 157 miles (normal), 149 miles (Sport). Real world in the colder weather I have been getting a bit less than predicted but in this warmer weather the predictions are not far off.

Contacted the dealer and asked them to check and they have assured me that the car has no recalls according to MG.

Puzzling!

I am keeping a close eye on the voltage at full charge which I am doing once a week (including equalisation which currently takes about 45 minutes). Will be back onto the dealer if there's any deterioration.

 

[JodyS21]

There are definitely different versions and possibly part implementations of revisions on MG cars.

I bought my ZS EV on 23 November 2020. The dealer assured me that all the software modules had been updated. Sure enough the Comfort 2 had been done and I can AC charge with the car locked or unlocked and delayed charging is OK.

So, my deduction is that I should have the bad BMS module released on 24 Oct 2020. However, I have no symptoms - at full charge the car shows 455 volts with GOM showing 173 miles (Eco), 157 miles (normal), 149 miles (Sport). Real world in the colder weather I have been getting a bit less than predicted but in this warmer weather the predictions are not far off.

Contacted the dealer and asked them to check and they have assured me that the car has no recalls according to MG.

Puzzling!

I am keeping a close eye on the voltage at full charge which I am doing once a week (including equalisation which currently takes about 45 minutes). Will be back onto the dealer if there's any deterioration.

I can't remember when the october really duff bms was pulled, but it could have been that the dealers were not putting it on the car when you got yours, that's why you haven't got problems.
It is highly likely that you have bms that can take an age to balance though (that's what the duff bms was trying to fix!), but you may well never notice it and it may well not cause you any issues. In which case it's not an urgent fix, it'd just get updated when next in for a service. I would suggest not going purposely and insist on the latest update, at least give it a few more weeks/months to be proved to not cause any other issues.

 

[JodyS21]

Regarding the displaying of Volts, and Amps drawn on the car.
I've been thinking about this A LOT!

My belief is that it is not of great use to us (under normal circumstances).

I really think it should be removed and replaced with a battery remaining capacity figure in kWh and, the current power draw on the car should be displayed in kW.
Watts is the only real figure, volts & amps are pretty much useless each on their own.

Furthermore, it would be really really nice if it showed in the trip data, the amount of regenerated power in kWh.


As a user of the car, I want to see how much battery capacity I have available. We all know batteries degrade over time, and unless we can see this we will not know what we have available in years to come.
The range Guess O Meter, is very much that a guess. As I user, I want to know what I really have available and then I can make a real educated guess for my journey & charges, related to what type of driving I know I'm going to be doing.

 

[Lovemyev]

It is highly likely that you have bms that can take an age to balance though (that's what the duff bms was trying to fix!),

If I have read his post correctly, he said his balancing process is only taking about 45 minutes ?.
Therefore no problem there I think.
His voltage on the pack after a full charge is 455 volts which would suggest he is running on “Pre Buggy” software.
But I agree with the OP that the dates would suggest he does have one of the “Buggy” updates though ???.
If all is well with the car, I would leave well alone to be honest.

 

[Electrifried]

Well I had my car in yesterday for the latest BMS update. This was because the previous update did nothing to improve the car. It did not allow the car to charge with doors locked although I could unlock the car with the button on the door handle and it would continue to charge. My main issue is it would not do a delayed charge with my home smart charger( it did it once). So I got it back from dealers and I immediately took it home to see if there were any improvements. First thing was I plugged in the charger with doors unlocked and yes it did charge, so that was an improvement. So we unplugged and set the charger for an overnight charge on cheap rate, after having the charger for 5 months and not been able to take full advantage of cheap rate charge was a nice feeling.
This morning charge was successful but the disappointing aspect was as others have stated the overall voltage has dropped from 456v down to 446v and the range has dropped by 20mls so not entirely happy considering the range has always been on the limits for our needs. We will just have to wait and see if it stays like this or improves after a few charges.

 

[Trevor]

I have had no issues with charging or mileage, but then I only use the granny charger, apart form on long trips. I usually charge overnight and then with everything turned off and on Eco it shows 203 miles. What makes you think I have a defective BMS? If you have the "EV only blue" and live in Bicester I have probably seen your car around! (Same colour as me)

EV only... But went for red.

 

[Trevor]

Well I had my car in yesterday for the latest BMS update. This was because the previous update did nothing to improve the car. It did not allow the car to charge with doors locked although I could unlock the car with the button on the door handle and it would continue to charge. My main issue is it would not do a delayed charge with my home smart charger( it did it once). So I got it back from dealers and I immediately took it home to see if there were any improvements. First thing was I plugged in the charger with doors unlocked and yes it did charge, so that was an improvement. So we unplugged and set the charger for an overnight charge on cheap rate, after having the charger for 5 months and not been able to take full advantage of cheap rate charge was a nice feeling.
This morning charge was successful but the disappointing aspect was as others have stated the overall voltage has dropped from 456v down to 446v and the range has dropped by 20mls so not entirely happy considering the range has always been on the limits for our needs. We will just have to wait and see if it stays like this or improves after a few charges.

If you haven't cleared "accumulated usage" then it would be worth checking GOM after doing so - you should see a significant improvement

 

[Paulie68]

I think you may be confusing a few different things Tim.. The ZS has always allowed rapid charging (DC) with doors unlocked. The ability to charge on AC (granny or fast charger) was originally only possible when the car was locked, and stopped as soon as you unlocked the car. The ability to charge on AC when locked was introduced as part or one of the BMS updates.

Changing the display to show the external temp came as part of the comfort 2 upgrade which also 'de-bonged' the car.

If you are running an early BMS version the car will likely 'go to sleep' and you won't be able to 'wake it up' if you want to use timed charging. If you have the summer 2020 BMS update you will probably get timed charging but the car will take ages to balance. If you have the late Oct 2020 BMS update the battery won't balance properly at all.

As far as we can tell the Jan 2021 allows charging on AC when car is unlocked, allows timed charging, and balances the battery properly. I'm still seeing long balancing times but maybe my battery is not back in balance yet, and this will settle down.

If you have an early BMS version, your car is performing well and you are not bothered about timed charges or stopping charging on AC when you unlock stick with what you have got.

Just to confirm, the Jan 2021 BMS update does not automatically give you charging on AC whilst unlocked, mine is updated and all working as expected, lower terminal voltage etc. but still needs to be locked to AC charge.

 

[Mark Holmes]

Well I had my car in yesterday for the latest BMS update. This was because the previous update did nothing to improve the car. It did not allow the car to charge with doors locked although I could unlock the car with the button on the door handle and it would continue to charge. My main issue is it would not do a delayed charge with my home smart charger( it did it once). So I got it back from dealers and I immediately took it home to see if there were any improvements. First thing was I plugged in the charger with doors unlocked and yes it did charge, so that was an improvement. So we unplugged and set the charger for an overnight charge on cheap rate, after having the charger for 5 months and not been able to take full advantage of cheap rate charge was a nice feeling.
This morning charge was successful but the disappointing aspect was as others have stated the overall voltage has dropped from 456v down to 446v and the range has dropped by 20mls so not entirely happy considering the range has always been on the limits for our needs. We will just have to wait and see if it stays like this or improves after a few charges.

Don’t forget it will take a few charges to get your battery back to where is should be, you need to make sure you do equalisation charges to get your battery balanced and back to full capacity, it takes a little time but eventually your voltage should go back to about 450