To update or not (BMS)

Royals

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MG ZS EV
New MG ZS EV first edition owner here.

My ZS EV build november 2020, seems to be on an older BMS. I asked for all latest updates on delivery, but I have no KERS when fully charged and the battery has 454voltage when full. So guess they said yes, but did nothing. (Shows 268km on E with HVAC off and 242 on E with HVAC on. If this helps any)

Are there other perks (or concerns) on the newer BMS version? Update or should I just leave it as it is.
Any other advise on how to check if I do have the latest other software updates installed?

I would like to do some timed charging in januari at my home when the charger is installed. If it helps: I did test to see if I unplug the granny from the powersocket and plug it back in, the car starts to charge again.
 
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I asked for all latest updates on delivery, but I have no KERS when fully charged and the battery has 454voltage when full.
Hi

You won't get any Regen from KERS when battery is 100% full because there's nowhere for the regenerated electrons to go. It'll kick in around 95-98% soc at a guess.
 
I only recently (August) had the BMS update for my car which was almost a year old at the time. The only difference I noticed is it seemed to balance after every charge whereas before I would have to usually put in on again the next evening to balance (charging at home).
 
You won't get any Regen from KERS when battery is 100% full because there's nowhere for the regenerated electrons to go. It'll kick in around 95-98% soc at a guess.
New BMS your KERS will work even when full from what I have seen in the forum. Thats why I stated it and figured I still have the older BMS.
 
IIRC, I think the old BMS charges to about 97% and the new one 93%.
I find that on mine, with the old BMS, in warm weather, KERS starts working again after you've run about 4 miles off the range, cold weather seems to extend that 4, to about 8 miles.
KERS works from the off on the new BMS, so I'd guess the threshold where it starts working again is maybe around 95%.
 
New MG ZS EV first edition owner here.

My ZS EV build november 2020, seems to be on an older BMS. I asked for all latest updates on delivery, but I have no KERS when fully charged and the battery has 454voltage when full. So guess they said yes, but did nothing. (Shows 268km on E with HVAC off and 242 on E with HVAC on. If this helps any)

Are there other perks (or concerns) on the newer BMS version? Update or should I just leave it as it is.
Any other advise on how to check if I do have the latest other software updates installed?

I would like to do some timed charging in januari at my home when the charger is installed. If it helps: I did test to see if I unplug the granny from the powersocket and plug it back in, the car starts to charge again.
I didn't do the update with my first service👍
New MG ZS EV first edition owner here.

My ZS EV build november 2020, seems to be on an older BMS. I asked for all latest updates on delivery, but I have no KERS when fully charged and the battery has 454voltage when full. So guess they said yes, but did nothing. (Shows 268km on E with HVAC off and 242 on E with HVAC on. If this helps any)

Are there other perks (or concerns) on the newer BMS version? Update or should I just leave it as it is.
Any other advise on how to check if I do have the latest other software updates installed?

I would like to do some timed charging in januari at my home when the charger is installed. If it helps: I did test to see if I unplug the granny from the powersocket and plug it back in, the car starts to charge again.
my mg is just as old .. I have chosen not to have the bms update performed.
Do you also have the problem that the gom occasionally jumps? it then simply indicates 30/40 kilometers less and then after a stop of 10 minutes there is a good chance that the kilometers are back. almost empty light is on .. but not in those cases so the right-hand bar meter is correct but the gom is not correct .. do you have that too?
 
With the upper limit of the battery being slightly lower when the new BMS is applied, it makes sense that the Regen is available earlier, because the recovered energy has somewhere to go !.
Should you have the new BMS done ?.
Well that is the 99 dollar question !.
MG have released a service bulletin that states that cars submitted for annual service, should have the latest BMS applied at the time of service.
Is this happening ?.
No, not at every dealership 😞.
Some owners who are still running on the factory software, have decided that if they are not experiencing any problems with their range, they are leaving well alone.
Leave sleeping dogs.
This is because some owners have had a bad experience, when certain dealers have made a poor attempt at applying the update.
Therefore they have steered away from having the update applied.
Some dealers are not offering the update, but will apply it by customer request.
This only displays their reluctance and confidence to carry out the work IMO.
I can totally understand why customers are shying away from having the work done.
If you do intend to go ahead with having the update, try and pick a dealer that has a previous record and experience of carrying out a number of these updates successfully !.
Of course, nobody knows long term if cars with or without the update will fair better over time.
If you have the latest update, your predicted range after a full charge and balance will be reported slightly lower than what you are seeing now.
The GOM reading will retain the same accuracy level after the update.
I am running on the latest BMS update.
Charging on A/C with the doors unlocked is not totally achieved by having JUST the latest BMS update done.
There is another “tick box” exercise that needs completed at the same time as the update.
Some dealers have missed off this process and charging with the doors unlocked will not work.
I think you know the drill on how to get a rough handle on what BMS update you have installed at present ?.
By checking the voltage / range etc.
As the customer, I don’t believe the owner should be getting the choice of picking if they get the update or not.
Otherwise, what is the whole point of releasing service bulletin's out to the dealers ?.
 
As the customer, I don’t believe the owner should be getting the choice of picking if they get the update or not.
Otherwise, what is the whole point of releasing service bulletin's out to the dealers ?.
I can understand why an owner should have a choice to decide to get the BMS update or not, after all it is now their vehicle they have paid for it. Just because it is software it does not give a dealer the right to change settings on a vehicle if the customer expressly states it is not to be updated.
However, I did agree to have my BMS updated, I could see no disadvantages (apart from if it's not broken don't fix it) and my car now has the same BMS as those rolling off the production line. Clearly the research carried out by MG indicated the need to update the software and therefore I felt it was worthwhile having the latest in my car.

For information the charge on a/c while unlocked is update EVCC 1770124111, which is the latest. It is not part of the BMS 0210622EU1 update.
 
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I can understand why an owner should have a choice to decide to get the BMS update or not, after all it is now their vehicle they have paid for it. Just because it is software it does not give a dealer the right to change settings on a vehicle if the customer expressly states it is not to be updated.
Although I do agree with your point of view that it still IS the owner property and he / she has the right to refuse the work, but I think we do have to consider the bigger picture a little bit here Dave.
The ZS EV comes with a 7 year warranty and as part of the conditions of upholding / maintaining that warranty, is that the owner submits the car for it's regular annual service intervals under the T&C's laid down.
Also, that any important safety service bulletins released by the manufacture, should also be applied at the time of that annual service.
This is one of the main reasons why manufactures strongly suggest using their dealer network, so manufactures software improvement gets applied at the point of service.
The warranty also includes the HV battery pack and therefore should be subject to similar T&C's.
Having worked in very large dealership myself many years ago, here is an hypothetical situation.
I relate this example to real attempted large warranty claims in my career.
E.G :- So, we have a four year old EV ( that is now more than half way through it's warranty period ) it has developed a major fault on the HV battery pack, it is determined that a large & substantial warranty claim is required to rectify the problem.
The very first place the manufacture will look, is the service history records of that car.
Trust me I know.
Service history is all in order - Great !.
Oh ....... But wait, they notice that the dealer has made a note on the system, that the owner has refused to allow them to apply the recommended update.
When this update was developed to help protect / improve the future life of the battery, but was not carried out earlier in the life of the car.
As a direct instruction from the owner of the car.
Well, I think we can quickly see where this is claim is heading !.
Refused on the grounds of none compliance under the T&C's of the warranty.
I have to say, this current non conformance situation has the potential of back firing in the faces of SOME of the dealers here in the future.
Why ? - SOME service departments are placing their heads firmly in the sand and avoiding carrying out the work, even though MG have documented evidence that they have received the service bulletin information.
If MG has gone to the trouble of issuing the service bulletin and is willing to pay for the labour costs, then surely THEY do consider the car needs them doing - plain and simple !.
Much cheaper than a possible future claim for a HV battery pack hey ?.
Dealers could circumnavigate this problem, by strongly suggesting / advising the customer that stress the importance of agreeing to the necessary updates.
But we know that many are not doing this.
It should be done correctly, by advising the customer of any important safety updates that the car requires.
If then customer / owner rejects the dealers advice, then it should be duly noted, then by doing so they will be forgoing / voiding any future claims under the T&C's of that warranty.
The current system is not robust in any way shape or form.
Let's hope this type of situation never arises of course.
But having personally seen warranty claims refused / rejected on a technical detail ( e.g. claim refused because the car was submitted for service outside of the 30 day time limit on service schedule ) it really is important to comply with the T&C's.
In main cases, it will largely depend on the size / cost of the warranty claim, just how far the service history of the car is studied.
With a claim on a HV pack, it's going to be both time consuming and very expensive in parts / labour and hire car costs.
But to keep this story balanced, I HAVE seen warranty claims accepted when cars are clearly just outside of warranty also.
These are settled on a "Sympathetic Claim or Gesture Of good Will" basis.
Again - A 100% solid dealer service history will be checked prior to granting the claim, you can be absolutely sure.
My son had a £3,000 "Sympathetic Claim" claim successfully paid out on a 3 year and 3 months old BMW with 25,000 miles on the clock.
It was a one owner car, service history was 100% bang on, the work was conducted at the same large BMW main dealers, each and every single time.
When agreeing the claim, BMW did so by pointing out that the service history had supported their decision in honouring the claim.
Food for thought at least.
 
All very interesting...
My car was purchased new in February 2020 and so had its first service in February this year. At the time the bulletins were full of BMS update problems so I told the garage not to do the update which they supported (not in writing of course).
As the BMS issue seems to have settled down now, I will probably ask for the new BMS update at the next service in Feb next year.
 
All very interesting...
My car was purchased new in February 2020 and so had its first service in February this year. At the time the bulletins were full of BMS update problems so I told the garage not to do the update which they supported (not in writing of course).
As the BMS issue seems to have settled down now, I will probably ask for the new BMS update at the next service in Feb next year.
Typical responce from a dealer who is “Ducking” around the issue.
 
My car had it's first service last month. Not at the supplying dealership but at my nearest which is a very small garage. When I booked it in I asked what software updates would be done. The response was "anything that is flagged up by MG that needed to be done". I didn't argue.

On the day of the service when I went to pick up the car I was served by the owner of the franchise. The BMS update had been done. I got chatting to the owner who told me that MG only allow them 1 hour labour for the first service and this is to include any software updates. He told me in many cases this isn't enough and they can be out of pocket for the service. He was thinking about charging for software updates separately.

I told him that he obviously needs to make a profit and if that means charging for software updates then so be it. However, I said the customer must know this in advance which they wouldn't do when I booked my car in.

Whether this is him just being a bit miffed that they were servicing a car that they didn't supply, I don't know. His demeanour wasn't the greatest tbh.

So, take from that what you will. I'm now on the new BMS and tbh haven't noticed any difference because of it!
 
Although I do agree with your point of view that it still IS the owner property and he / she has the right to refuse the work, but I think we do have to consider the bigger picture a little bit here Dave.
The ZS EV comes with a 7 year warranty and as part of the conditions of upholding / maintaining that warranty, is that the owner submits the car for it's regular annual service intervals under the T&C's laid down.
Also, that any important safety service bulletins released by the manufacture, should also be applied at the time of that annual service.
This is one of the main reasons why manufactures strongly suggest using their dealer network, so manufactures software improvement gets applied at the point of service.
The warranty also includes the HV battery pack and therefore should be subject to similar T&C's.
Having worked in very large dealership myself many years ago, here is an hypothetical situation.
I relate this example to real attempted large warranty claims in my career.
E.G :- So, we have a four year old EV ( that is now more than half way through it's warranty period ) it has developed a major fault on the HV battery pack, it is determined that a large & substantial warranty claim is required to rectify the problem.
The very first place the manufacture will look, is the service history records of that car.
Trust me I know.
Service history is all in order - Great !.
Oh ....... But wait, they notice that the dealer has made a note on the system, that the owner has refused to allow them to apply the recommended update.
When this update was developed to help protect / improve the future life of the battery, but was not carried out earlier in the life of the car.
As a direct instruction from the owner of the car.
Well, I think we can quickly see where this is claim is heading !.
Refused on the grounds of none compliance under the T&C's of the warranty.
I have to say, this current non conformance situation has the potential of back firing in the faces of SOME of the dealers here in the future.
Why ? - SOME service departments are placing their heads firmly in the sand and avoiding carrying out the work, even though MG have documented evidence that they have received the service bulletin information.
If MG has gone to the trouble of issuing the service bulletin and is willing to pay for the labour costs, then surely THEY do consider the car needs them doing - plain and simple !.
Much cheaper than a possible future claim for a HV battery pack hey ?.
Dealers could circumnavigate this problem, by strongly suggesting / advising the customer that stress the importance of agreeing to the necessary updates.
But we know that many are not doing this.
It should be done correctly, by advising the customer of any important safety updates that the car requires.
If then customer / owner rejects the dealers advice, then it should be duly noted, then by doing so they will be forgoing / voiding any future claims under the T&C's of that warranty.
The current system is not robust in any way shape or form.
Let's hope this type of situation never arises of course.
But having personally seen warranty claims refused / rejected on a technical detail ( e.g. claim refused because the car was submitted for service outside of the 30 day time limit on service schedule ) it really is important to comply with the T&C's.
In main cases, it will largely depend on the size / cost of the warranty claim, just how far the service history of the car is studied.
With a claim on a HV pack, it's going to be both time consuming and very expensive in parts / labour and hire car costs.
But to keep this story balanced, I HAVE seen warranty claims accepted when cars are clearly just outside of warranty also.
These are settled on a "Sympathetic Claim or Gesture Of good Will" basis.
Again - A 100% solid dealer service history will be checked prior to granting the claim, you can be absolutely sure.
My son had a £3,000 "Sympathetic Claim" claim successfully paid out on a 3 year and 3 months old BMW with 25,000 miles on the clock.
It was a one owner car, service history was 100% bang on, the work was conducted at the same large BMW main dealers, each and every single time.
When agreeing the claim, BMW did so by pointing out that the service history had supported their decision in honouring the claim.
Food for thought at least.
I have agreed it is better to have the BMS update however your warranty argument is flawed. It is not work required under recall and therefore not under the terms and conditions of a service to maintain warranty. As you would be aware to maintain warranty a car service can be carried out by any vat registered dealer not just MG dealerships all they have to do is follow the manufactures service schedule. This complies with MG warranty terms and conditions. The last time I checked the MG EV schedule it did not stipulate a BMS update (There are legal reasons why MG cannot include a BMS update on the service schedule). In addition the BMS update is not on a safety bulletin as you have suggested.

The law is clear in this matter, hypothetical examples do not add to the argument. I could put forward dozens of real life examples which have gone to court.
 
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I think Miles had suggested that it is possible, that only certain updates will be sent via OTA.
Larger more important / critical updates ( maybe BMS 🤫 ? ) may still require a visit to the dealers.
We will see I guess ???????.
HOPEFULLY - Their has been lessons learnt on the previous model, that will prevent a repeat of the quick fire release of major updates, too soon in the face lifts models life.
"Slowly, slowly, catchy monkey" as the old saying goes.
 
I think Miles had suggested that it is possible, that only certain updates will be sent via OTA.
Larger more important / critical updates ( maybe BMS 🤫 ? ) may still require a visit to the dealers.
We will see I guess ???????.
HOPEFULLY - Their has been lessons learnt on the previous model, that will prevent a repeat of the quick fire release of major updates, too soon in the face lifts models life.
"Slowly, slowly, catchy monkey" as the old saying goes.
I am not in the market for a Gen2 (yet!) but if I was then OTA would concern me.
 
I think Miles had suggested that it is possible, that only certain updates will be sent via OTA.
Larger more important / critical updates ( maybe BMS 🤫 ? ) may still require a visit to the dealers.
We will see I guess ???????.
HOPEFULLY - Their has been lessons learnt on the previous model, that will prevent a repeat of the quick fire release of major updates, too soon in the face lifts models life.
"Slowly, slowly, catchy monkey" as the old saying goes.
I just read earlier, Miles say that he asked MG, and they said the ECUs can be updated OTA too. Obviously we'll have to wait for a while to see that if it is definitely true. (Some things it will always be necessary for a dealer to plug in and do)
 
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