MG EVs special podcast: All your MZ ZS EV BMS Bug Frequently Asked Questions ANSWERED

[Stuart Wright]

In the latter part of 2020, some MG ZS EVs had a software version installed which contained a bug which caused the batteries to become imbalanced. In this interview, Miles Roberts will answer the questions that the MG EVs community have about this software update.



00:00:00 - Introduction
00:04:08 - How is the software in EVs different to the software in ICE cars?
00:07:06 - Do EVs have more frequent software updates than ICE cars?
00:12:00 - How are software updates to MG electric cars installed?
00:12:37 - What changes to the ZS EV have been made with the updates?
00:18:08 - How to identify what version of the software is installed?
00:19:02 - What is the BMS and what does it do?
00:19:40 - Is the BMS separate to the other software in the car?
00:22:09 - Can MG ZS EV owners see the battery health?
00:22:55 - What should the voltage display read for the ZS EV?
00:25:20 - What if the voltage display reads something else?
00:27:29 - What is balancing the battery and what causes an imbalanced battery?
00:29:44 - How long does battery balancing normally take?
00:30:50 - Does rapid charging create more of an imbalance?
00:31:12 - How do I ensure my battery is balanced?
00:31:33 - Does cell voltage balancing happen on all EVs?
00:32:13 - Is battery balancing an automatic process?
00:33:10 - Which particular ZS EV software update caused imbalanced batteries?
00:34:43 - How many cars were affected by the bad BMS software?
00:35:00 - What was the actual problem with the late 2020 BMS software?
00:35:31 - Does this software update affect other MG models?
00:36:06 - What impact will an imbalanced battery have on the car?
00:38:27 - Will having an imbalanced battery damage the battery or car?
00:39:05 - What should an owner who believes they have the bad BMS do?
00:40:50 - Have ZS EV owners with the particular software version been contacted to update it?
00:42:44 - What is the procedure for re-balancing and how long does it take?
00:47:48 - Should people re-balance while they have the bad BMS?
00:48:48 - What is the latest version of the ZS EV software and when was it released?

If you find the MG EVs forum and this podcast useful, then please consider becoming a Premium Member for just £3+VAT per month. Details at https://www.mgevs.com/account/upgrades

 

[Cocijo]

Excellent - thanks. Quick question for Miles.
can I get one of the illuminated MG logo signs that’s behind him on the podcast?
?

 

[jamesie]

Excellent podcast.

Further question - will unaffected cars i.e. those balancing to 455 volts, get the new BMS software at the next service?

 

[Jake]

Thank you Stuart and Miles for taking the time to produce a very informative explanation of a currently hot topic. As already stated above - Excellent.

 

[Lovemyev]

Excellent podcast.

Further question - will unaffected cars i.e. those balancing to 455 volts, get the new BMS software at the next service?

I did suggest the very same question ready for the Pod Cast, but it was not discussed.

 

[Dave53]

In the latter part of 2020, some MG ZS EVs had a software version installed which contained a bug which caused the batteries to become imbalanced. In this interview, Miles Roberts will answer the questions that the MG EVs community have about this software update.



00:00:00 - Introduction
00:04:08 - How is the software in EVs different to the software in ICE cars?
00:07:06 - Do EVs have more frequent software updates than ICE cars?
00:12:00 - How are software updates to MG electric cars installed?
00:12:37 - What changes to the ZS EV have been made with the updates?
00:18:08 - How to identify what version of the software is installed?
00:19:02 - What is the BMS and what does it do?
00:19:40 - Is the BMS separate to the other software in the car?
00:22:09 - Can MG ZS EV owners see the battery health?
00:22:55 - What should the voltage display read for the ZS EV?
00:25:20 - What if the voltage display reads something else?
00:27:29 - What is balancing the battery and what causes an imbalanced battery?
00:29:44 - How long does battery balancing normally take?
00:30:50 - Does rapid charging create more of an imbalance?
00:31:12 - How do I ensure my battery is balanced?
00:31:33 - Does cell voltage balancing happen on all EVs?
00:32:13 - Is battery balancing an automatic process?
00:33:10 - Which particular ZS EV software update caused imbalanced batteries?
00:34:43 - How many cars were affected by the bad BMS software?
00:35:00 - What was the actual problem with the late 2020 BMS software?
00:35:31 - Does this software update affect other MG models?
00:36:06 - What impact will an imbalanced battery have on the car?
00:38:27 - Will having an imbalanced battery damage the battery or car?
00:39:05 - What should an owner who believes they have the bad BMS do?
00:40:50 - Have ZS EV owners with the particular software version been contacted to update it?
00:42:44 - What is the procedure for re-balancing and how long does it take?
00:47:48 - Should people re-balance while they have the bad BMS?
00:48:48 - What is the latest version of the ZS EV software and when was it released?

If you find the MG EVs forum and this podcast useful, then please consider becoming a Premium Member for just £3+VAT per month. Details at https://www.mgevs.com/account/upgrades

Very informative podcast, I did notice Miles being diplomatic calling the BMS Battery Monitoring System.

 

[Cocijo]

Yes I noticed that...

 

[Dave53]

Excellent - thanks. Quick question for Miles.
can I get one of the illuminated MG logo signs that’s behind him on the podcast?
?

Probibly cost 2 grand, from MG store???

 

[Cocijo]

I wonder of it glows...

 

[DanRiz]

Thanks so much to Stuart and Miles for making this video and for all the other podcasts you both put your time and effort into. It's very much appreciated! Thank you