SE balancing post update

[gazza487]

Always balanced my 4 half an hour drawing low levels.

Post update it was going for 2.5 hours … I had to stop it as I was going to work. Is that normal ?

 

[Alb]

It may not have been what you previously saw but there's nothing abnormal about that timescale.

 

[siteguru]

Maybe it wasn't balancing properly before, so has a lot more to do now?

 

[gazza487]

Maybe it wasn't balancing properly before, so has a lot more to do now?

Exactly what I’m thinking, it definitely pulled in a new BMS update.

I’ll give it a go after work and leave it for as long as humanly possible. Definitely the longest I’ve ever seen it attempt to go.

 

[Rolfe]

I've occasionally seen mine go on for ages, although 35 minutes is normal.

 

[gazza487]

You can see where she kept on going - the large peak is where I was defrosting.

Will see what happens later but it MUST be down to new SW whatever changes they have made which says to me they know that something needed changing so might be worth ensuring your cars are updated.

 

[gazza487]

A normal balance for reference a week or two ago.

 

[fnegroni]

You can see where she kept on going - the large peak is where I was defrosting.

Will see what happens later but it MUST be down to new SW whatever changes they have made which says to me they know that something needed changing so might be worth ensuring your cars are updated.

What was the outside temperature?

 

[gazza487]

What was the outside temperature?

Approx 1°C.

 

[fnegroni]

Approx 1c

I’m wondering if the battery was cooling down as it was balancing: as the battery gets colder, the voltage lowers too.
Maybe that new BMS now takes that into account

 

[gazza487]

Pass but it is very interesting. I’m half tempted to plug in and make sure the update applied correctly (I’m sure it did as I was fiddling for hours and hours and hours at the weekend).

I’ll let it do what it wants later but it’s a very interesting change. Makes me think it’s not looked after itself in my years of ownership.

 

[gazza487]

The plot thickens. My estimated range is now higher than normal - wonder if I’ve gained some capacity back…… most interesting. Attached are old module numbers - never took a shot of the new ones (I’d already done HVAC and FICM at that point too).

I’ll let it do its thing. Plug my autel in and see what it reports as SOH - few weeks ago it was just below 93% - and report backs.

 

[siteguru]

Check your Accumulated Total trip counter - that probably got reset when you updated the software, and so the GoM resets to pretty much WLTP range. (173 miles at 86% equates to about 201 miles at 100%).

 

[Rolfe]

I had a situation that may or may not be similar, last winter. I started a thread about it at the time. Might be relevant?

Thread 'Unusual charging behaviour at the end of an AC charge.'

Mar 5, 2024

Since I got my car (SR, LFP battery) I have noticed consistent behaviour on AC charging. The app will give an estimated finish time, and round about that time the charging power would fall from about 1.88 kw (on the granny charger) or about 6.5 kw (on a type 2) to negligible, usually about 20 watts. It would go on drawing that small amount of power (can't be seen now on the new app which only gives one digit after the decimal point) for about 30-35 minutes, and during that time the estimated finish time displayed would be the current time. Eventually, when the balancing was complete, the...

• Rolfe
• ac charge behaviour charging charging power mg4 unusual
• Replies: 15
• Forum: MG4 EV Forum

• 

 

[gazza487]

I had a situation that may or may not be similar, last winter. I started a thread about it at the time. Might be relevant?

Thread 'Unusual charging behaviour at the end of an AC charge.'

Mar 5, 2024

Since I got my car (SR, LFP battery) I have noticed consistent behaviour on AC charging. The app will give an estimated finish time, and round about that time the charging power would fall from about 1.88 kw (on the granny charger) or about 6.5 kw (on a type 2) to negligible, usually about 20 watts. It would go on drawing that small amount of power (can't be seen now on the new app which only gives one digit after the decimal point) for about 30-35 minutes, and during that time the estimated finish time displayed would be the current time. Eventually, when the balancing was complete, the...

• Rolfe
• ac charge behaviour charging charging power mg4 unusual
• Replies: 15
• Forum: MG4 EV Forum

• 

Thanks I don’t think this is the same. I’ve had what you describe before in the cold - I assumed it was the battery heater looking after the pack of its own accord.

This is an incredibly long balance, which I ran out of time completing due to having to go to work. Something has changed my journey to and from work is reliably 16% of my battery (each way) a bit more when it’s fully charged due to defrost, lack of regen etc. attached is today …

If this is the case I’m inclined to say (SE SR people at least), run to the updates.

 

[Rolfe]

I remember something similar to what you describe happening to me just before Christmas. I was staying with friends and the car was on a public 7 kw charger just a couple of minutes walk from their house (how handy is that?) I was watching the app to see when the car had finished charging so I could walk over and fetch it back to their driveway. To the best of my recollection it was well over two hours before it finally decided it was done.

 

[siteguru]

I have mine on charge right now - estimated to complete at 20:51 according to the app. I'll try to remember to take a look and see what time it actually finishes.

 

[gazza487]

Weird car. It topped itself off with no real balancing that I could see.

Think a few cycles of flattening and full charging are in order - see if I can make the odd low SOC power restrictions disappear. Will re read the SOH too for reference. I did have another thought - post update I tested it on a DC charger (being cold I put in around 10ish) I wonder…..

 

[siteguru]

I have mine on charge right now - estimated to complete at 20:51 according to the app. I'll try to remember to take a look and see what time it actually finishes.

I forgot to check the app (I was at the pub ) but I got a notification from my charge point app that suggests the charge finished at around 21:30, so about 40 minutes after the predicted finish time I'd seen earlier.

In other news (as I can't easily find the thread) ... @Rolfe I left my car plugged in overnight so it was plugged in not charging this morning. I started remote cabin preheat without any issues. I also started battery heating as a test too ... with both running, by the time I went out to walk the dogs I noticed that the car was charging again. So it looks like my car is doing everything as would be expected.

 

[Rolfe]

Thanks. I think mine has a software issue.