BMS update-Computer says “No”

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As mine has the long cell balancing issue, but not the range loss, I'm lucky I can wait for others to be beta testers of this update and probably won't get an update till service in September, but that isn't ideal, given lockdown, we could really do with MG loaning some ZS's with this new BMS update to keyworkers who can use the car to get to and from work and test it while most of us are putting a couple of miles a day at most on our cars for the next how many months. This needs to be fully tested now while it is cold, as I wouldn't want warmer weather to mask some of the issues come the Spring when we will hopefully be able to stretch the legs on our cars again.
 
Many thanks to Miles for the update. My concern is that the update is going to be available next week, how much testing has been done to it. So yet again owners will become beta testers for MG again.

As to what is on my car, I will be contacting my dealer/MG to request all the information that they hold on me (subject access request) which they must supply. Including the service record as my car identifies me. Then we will see what is recorded .
Pretty sure they won’t need to get into that level of detail for a SAR since the work the car has had doesn’t identify you in the slightest.

Maybe you could try asking them in a way that makes you sound less self righteous and they’ll comply?
 
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Unfortunately, the software versions are only readable with the MG diagnostic laptop which the dealers use, so you'd have to take it to a dealer and ask them to check.
Thanks for the reply and will do.
 
The engineering team at Longbridge do have ZS EVs, which they are testing the software on this week. I'd offer to test it myself, but I'm in an MG5 now, and we don't have any spare ZS EVs at Burnley for me to swap into.
Miles, just for comparison and you now driving a 5. How does the MG5 compare with the amount of issues/concern people seem to have with ZSev including any software.
I hoping much less concerns with the 5 as its predominantly based on the Ei5 thats been around a while.
 
Miles, just for comparison and you now driving a 5. How does the MG5 compare with the amount of issues/concern people seem to have with ZSev including any software.
I hoping much less concerns with the 5 as its predominantly based on the Ei5 thats been around a while.
A lot of the software issues were fixed before launch. So things like the comfort 2 update regarding bongs etc were never an issue for the MG5. Obviously it doesn't have MG Pilot, so that takes a load of sensors out of the equation. There's no camera to be obscured by condensation, nor speed camera recognition...
But on the whole it's working well. Not had any issues with getting timed charging working. Range seems to be holding up fairly well given the weather (not done any long continuous journeys, due to lockdown, but my numerous short journeys with heating on 22°c this past week has resulted in around 150 miles to a charge.
 
I don't know if it will fix all issues with the coldgate battery heater option, but it's certainly compatible with it, and should fix the range related issues. Not sure if it will actually make the heater work though.
Many thanks Miles... I am due to take my car in on Monday which I suspect is now too early...Is it possible for dealer to remove update until new onw comes in...I need the mileage for work
 
Thanks but the update was carried oiut at first recent first service.... I hope they can reset it back to pre update on Monday
You can't rollback the updates once they are on the car. However, if it was recently carried out at 1st service, there's a chance that MG's server had already been rolled back to the July update (which, whilst taking a long time to do an upper balance, doesn't cause range issues).
 
I have just registered purely to be able to add my thanks to everyone on the forum who provides help, advice, community and reassurance, in this instance particularly Miles.

I recently (mid-December) had the BMS update done and noticed a significant reduction in projected range, which had caused me, unsurprisingly, dismay and anxiety. So to find on here from members that the issue will hopefully be resolved is a great weight off my mind. (I don't want to blow my own trumpet ... but I'm going to ... but I am an NHS worker - I know, hero!! :cool: - and I have a lot of miles to do over the next couple of weeks). Even if I struggle, at least I know there is possible light at the end of the tunnel with an update after this 🤞!
Thanks again to all!
 
Hi all,
I've had confirmation today that MG has spotted a bug in the BMS code from the recent August/October updates.
It looks like the August update caused cell balancing issues when full (so the end balance took 5hours or so). They tried to rectify this in the October update, but then found that this caused cell balancing issues when SOC was lower. This has caused range issues, as the car isn't able to use the full pack capacity.
By the end of next week, there will be a new BMS update released to the dealer network, which will be able to fix the affected vehicles.
Thanks for providing some clarification of the 'BMS Update' issues Miles, it is really appreciated.

My ZS was updated by your good selves on the 20th October, I appear to have crept into the August update as I am not experiencing the range/voltage issues seen by others. I do however have the circa 5hours balancing at the end of my charge:

Screenshot_20210106-182952.png
 
I have both BMS updates and the heater update (don’t bother with it).

My max voltage is 448V so in between the okay and bad, and that is reflected in my range.

On a warm battery after a rapid charge I managed 74 miles on 80%, arriving home with 12%. It was 1°C ambient, the battery coolant was 15°C according to OVMS.
 
All charged mine last night and this morning I had 454 volts, it may have lots a little overnight or perhaps I lost a little battery capacity over the 13,000 miles which isn’t so bad as degradation compared to other EV car makers...
I think Mike Proctor said he’d also only lost 1% over a year and 12,000 miles too.

All charged mine last night and this morning I had 454 volts, it may have lots a little overnight or perhaps I lost a little battery capacity over the 13,000 miles which isn’t so bad as degradation compared to other EV car makers...
I think Mike Proctor said he’d also only lost 1% over a year and 12,000 miles too.
Hi, how does your car GOM show 191mls on 100% charge?
My always show 163mls when is New and after 6 months and 14800mls on the GOM, show 156mls.
 
Hi Taliano2,
To be honest I don’t know mine shot up following the comfort 2 updates, however don’t be to worried I my range hasn’t really increased and in the summer I can get about 173 - 178 miles on a run and nearer 215 in and around the city and therefore it’s a little deceiving, but I’m used to it now.
On my first service I’m going to ask for the Comfort 2 to be installed again and therefore this maybe corrected, prior to the update my range showed about 173 to 178 on a full charge on ECO from what a recall.
 
Hi Taliano2,
To be honest I don’t know mine shot up following the comfort 2 updates, however don’t be to worried I my range hasn’t really increased and in the summer I can get about 173 - 178 miles on a run and nearer 215 in and around the city and therefore it’s a little deceiving, but I’m used to it now.
On my first service I’m going to ask for the Comfort 2 to be installed again and therefore this maybe corrected, prior to the update my range showed about 173 to 178 on a full charge on ECO from what a recall.
I have the comfort 2 updates as well, but don't change the range in the dash, still as normal. I just have my first service done last week, they did more updates, and I noticed the regeneration 3 is little be more smooth then before also changing with unlock door.
 
I have the comfort 2 updates as well, but don't change the range in the dash, still as normal. I just have my first service done last week, they did more updates, and I noticed the regeneration 3 is little be more smooth then before also changing with unlock door.
You may want to check the BMS update that allows you to home charge with the doors unlock or open; the update has been pulled and it will be replaced with another BMS update as it had a problem and has reduced a lot of people’s range as from what I recall it reduced the amount of battery available to be charged, but speak to your dealer they should be able to advise you, but it’s been a big discussion point on this forum.
 
A lot of the software issues were fixed before launch. So things like the comfort 2 update regarding bongs etc were never an issue for the MG5. Obviously it doesn't have MG Pilot, so that takes a load of sensors out of the equation. There's no camera to be obscured by condensation, nor speed camera recognition...
But on the whole it's working well. Not had any issues with getting timed charging working. Range seems to be holding up fairly well given the weather (not done any long continuous journeys, due to lockdown, but my numerous short journeys with heating on 22°c this past week has resulted in around 150 miles to a charge.
Hi Mike, I read you have a MG5 now.
What you say about the range in winter?
I have the ZS EV, and I use for taxi, my miles per Kw is around 2.8 to 3.0 kW per mile now, on in winter, driving around London, city drive. I think to change to MG5 because the battery size.
 
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