25/01/21: Just had latest BMS software. Observations...

So this is odd...

I put my car onto charge at 12:00 pm and it was 92%, charging at 6kwh. Had a look at 4:30pm and it had finished equalising. I unlocked the car and then it started equalising again so I left it a bit.

Had a message on my Ohme app that the charge had finished, so I checked the car again and the MG light was off. I unplugged, then switched the car on and it showed that I had 444v again, but with less mileage than when it was fully charged this morning (full charge this morning was 147 miles, full charge this evening showing as 146 miles - both on Normal mode, everything switched off).
Don't put to much in that GOM reading, after all it is guessing on how you have been driving previously.
 
So this is odd...

I put my car onto charge at 12:00 pm and it was 92%, charging at 6kwh. Had a look at 4:30pm and it had finished equalising.
This is similar to what I am seeing in some respects.
My charge started at 92% but was only charging at 4.0kw according to my energy monitor.
I started at 11.30am this morning and it is STILL balancing at 6.50pm !.
I could have charged my battery from a very low SOC to full in that time, before this BMS update !.
 
Random question, but does temperature effect the voltage in any way? So the colder it is, the lower the volts?
 
Has anybody who's had the latest BMS update had over 450v yet?
I can not tell you, because my car is still stuck on its first charge / balance after the BMS update.
The car was at 92% when put it on charge this morning at 11.30am.
It is now almost 9.00pm and it is STILL balancing the pack.
This is pattern renders the car almost unusable if it is going to take this length of time.
Before the update I could have fully charged my car almost twice in this time !.
Not looking good as a fix in my book.
 
I can not tell you, because my car is still stuck on its first charge / balance after the BMS update.
The car was at 92% when put it on charge this morning at 11.30am.
It is now almost 9.00pm and it is STILL balancing the pack.
This is pattern renders the car almost unusable if it is going to take this length of time.
Before the update I could have fully charged my car almost twice in this time !.
Not looking good as a fix in my book.
Holy Guacamole!

May be worth calling the dealer about it.
 
Hi MAS I got my car from Glyn Hopkin East London on 23rd. Been waiting on a call back from workshop after sales passed on my email as not getting range or correct 455v. Did you phone or book your car online under Service MOT section on website? How long did they take to do BMS update? Were you able to wait inside?

Hi MAS I got my car from Glyn Hopkin East London on 23rd. Been waiting on a call back from workshop after sales passed on my email as not getting range or correct 455v. Did you phone or book your car online under Service MOT section on website? How long did they take to do BMS update? Were you able to wait inside?
Hi Dave, sorry did not see your message until today. I called Glyn Hopkin at Romford at 01708242744 and selected service department. They transferred me to East London Glyn Hopkin and spoke to Dave who booked me in for the next available appointment. I left the car at 11.30 and got call back at 4.30 pm. Please take both keys with you when you go for the update.
 
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This is similar to what I am seeing in some respects.
My charge started at 92% but was only charging at 4.0kw according to my energy monitor.
I started at 11.30am this morning and it is STILL balancing at 6.50pm !.
I could have charged my battery from a very low SOC to full in that time, before this BMS update !.
The garage made a point if saying it will take weeks for the car to fully balance the batteries.

I don't think my battery was very unbalanced but it did take a long time on balancing. It was in excess of 6 hours probably around 12!.
I read the stopped charging message in the Ohme app in the morning and didn't register the time.
 
Well - Finally at last the balance has completed at between 9.45pm and 10.00pm.
The car had sent a signal to the wall box and closed the contactor.
So, it had taken 4 hours to complete the BALANCE only.
The range is still at 153 miles of range, the voltage on the pack is at 449 volts.
This is identical to the figure that the car was displaying when I collected the car from the dealership.
Time range from start to finish :-
Commenced from 92% SOC at 11.30am and completely finished the entire process at 10.45pm.
Over ten hours in total !.
That is a LONG slog from an already 92% SOC.
Gods knows how long it would have taken from a lower SOC !.
Not even close to be usable in normal day to day use for longer trips.
Prior to the BMS upgrade, I could FULLY charge the pack in much much less time than this.
 
Well - Finally at last the balance has completed at between 9.45pm and 10.00pm.
The car had sent a signal to the wall box and closed the contactor.
So, it had taken 4 hours to complete the BALANCE only.
The range is still at 153 miles of range, the voltage on the pack is at 449 volts.
This is identical to the figure that the car was displaying when I collected the car from the dealership.
Time range from start to finish :-
Commenced from 92% SOC at 11.30am and completely finished the entire process at 10.45pm.
Over ten hours in total !.
That is a LONG slog from an already 92% SOC.
Gods knows how long it would have taken from a lower SOC !.
Not even close to be usable in normal day to day use for longer trips.
Prior to the BMS upgrade, I could FULLY charge the pack in much much less time than this.
Mine also is at 449v after balancing the first time.
 
After reading all of these headaches regarding the updates, is it worth telling my dealer not to update a single thing before I pick my pre-reg up in a few weeks? Many here seem to believe in, 'If it ain't broke...'

But if it's already had the updates, I fear I'll have a very low patience threshold for this stuff as my technical know-how isn't great. Sounds like you need an additional degree to get your head around all of the acceptable volts and mileage.
 
So this is odd...

I put my car onto charge at 12:00 pm and it was 92%, charging at 6kwh. Had a look at 4:30pm and it had finished equalising. I unlocked the car and then it started equalising again so I left it a bit.

Had a message on my Ohme app that the charge had finished, so I checked the car again and the MG light was off. I unplugged, then switched the car on and it showed that I had 444v again, but with less mileage than when it was fully charged this morning (full charge this morning was 147 miles, full charge this evening showing as 146 miles - both on Normal mode, everything switched off).
Was it colder in the evening?
Random question, but does temperature effect the voltage in any way? So the colder it is, the lower the volts?
Shouldn’t affect the voltage as far as I’m aware, but the GOM will be less if it’s colder.
 
I've not had issues with mine after the latest update. The voltage has dropped to a maximum of 450v, but my range hasn't changed and my regen seems more responsive than before the update.
 
Hi Dave, sorry did not see your message until today. I called Glyn Hopkin at Romford at 01708242744 and selected service department. They transferred me to East London Glyn Hopkin and spoke to Dave who booked me in for the next available appointment. I left the car at 11.30 and got call back at 4.30 pm. Please take both keys with you when you go for the update.
Hi Thanks for getting back to me. I finally got a call back from Dave and my car is booked in for new BMS update on Monday 1st. As I'm coming from Southend they agreed I could wait on it being done as it should be around 40 minutes. I'm glad you mentioned about taking spare key as Garage did not mention it. I have seen someone have problems on a youtube video when he couldn't get a comfort 2 update as he didn't have spare key with him. Cheers
 
Hi Thanks for getting back to me. I finally got a call back from Dave and my car is booked in for new BMS update on Monday 1st. As I'm coming from Southend they agreed I could wait on it being done as it should be around 40 minutes. I'm glad you mentioned about taking spare key as Garage did not mention it. I have seen someone have problems on a youtube video when he couldn't get a comfort 2 update as he didn't have spare key with him. Cheers
My dealer told me to bring my spare key as both are needed to do the update.
 
Hi Thanks for getting back to me. I finally got a call back from Dave and my car is booked in for new BMS update on Monday 1st. As I'm coming from Southend they agreed I could wait on it being done as it should be around 40 minutes. I'm glad you mentioned about taking spare key as Garage did not mention it. I have seen someone have problems on a youtube video when he couldn't get a comfort 2 update as he didn't have spare key with him. Cheers
I was not told as well, so I had to go back home to get it. May be a feedback on dealer, or I will email head office.
 
After reading all of these headaches regarding the updates, is it worth telling my dealer not to update a single thing before I pick my pre-reg up in a few weeks? Many here seem to believe in, 'If it ain't broke...'

But if it's already had the updates, I fear I'll have a very low patience threshold for this stuff as my technical know-how isn't great. Sounds like you need an additional degree to get your head around all of the acceptable volts and mileage.
I’m picking my pre-reg up this week.
I’ve specifically told them to make sure it has the latest update on it.

I know it seems a bit complicated what is going on, if you follow the timeline on updates though it all makes sense.

We won’t have the issues that others are having with regard to the hours of balancing charges being needed, as our cars haven’t been used so the batteries will be in new/top condition.

It’s folk who’s cars that have had the buggy Battery Management System update, and then used them lots that are having the major balancing issues. The more they’re used/recharged having the buggy BMS, the more their batteries will be out of balance and, therefore will take longer to now get “fixed” to a proper fully balanced state.
 
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