Mg ZS EV 2021

[mgzsev2021]

Hi there,

After owning a Nissan Leaf we have bought a 2021 Mg ZS EV, the car has only done 36000 miles however we have a problem, when we charge the car it only takes on approximately 20kw however it still shows 100% charge. Dealer says the car battery is ok and that we need to run it down to zero percent and then granny charge. We have done this and still the car is only taking on approximately 20kw, I suspect the last owner did a lot of rapid charging and the cells are un-balanced, has anyone had experience of this and did granny charging eventually fix the issue?


Thanks in advance!

 

[Alb]

What's the SOH of your battery?

 

[mgzsev2021]

Not sure, is there a way to find this out without taking it to a garage? After taking it to a local MG dealer they said degradation on one cell but not enough to worry about did forget to ask about the SOH!

 

[Catsailor]

Hi there,

After owning a Nissan Leaf we have bought a 2021 Mg ZS EV, the car has only done 36000 miles however we have a problem, when we charge the car it only takes on approximately 20kw however it still shows 100% charge. Dealer says the car battery is ok and that we need to run it down to zero percent and then granny charge. We have done this and still the car is only taking on approximately 20kw, I suspect the last owner did a lot of rapid charging and the cells are un-balanced, has anyone had experience of this and did granny charging eventually fix the issue?


Thanks in advance!

Battery warranty?

 

[mgzsev2021]

All a bit messy, long story, dealer said it had been serviced my mg until last year last service was more than 12 months ago so wouldn’t honor the warranty, having had a leaf this didn’t worry us as our car was sinilar age and mileage so expected similar range. On dropping the car off at a local Mg dealer they had no recollection of the car been serviced. We have a two year RAC warranty from the dealer who sold it to us. The local Mg dealer was the one who checked it and said granny charging should balance and rectify the problem. Sounds messy I know! I’m assuming the Mg dealer didn’t spot any battery issues as they said it all looked ok. It’s hard who to know and what to believe. The reason for posting here was to see if anyone else and a similar issue!!

 

[poldark]

An OBD2 dongle and CarScanner App will give you cell differential info.

Also dealer advice to do a top balance charge was good, but I believe it may take several to help improve any cell imbalance, perhaps 4-5 even.

So every time the battery status is below 20% (red zone) use an AC home charge and ensure it stays charging well beyond showing 100%. You need to check on your charger that the output is 0 volts before switching off.

 

[fred12345]

when we charge the car it only takes on approximately 20kw however it still shows 100% charge.

Yes but from what percentage of the battery you charge? If you charge when the car is on about 40%-50%, it won't take much more than 20kW to be at 100% ...
Could you confirm please?

 

[poldark]

And it can still be charging/balancing when showing 100%

 

[mgzsev2021]

Tried uploading a photo from today’s drive:

59 miles from 7 of 8 bars, 2021 model doesn’t show percentage!!!!
3.8 miles per kwh
Range left is not showing so less than 10 miles remaining.
Going to slow charge and see what happens.

Will repeat four or five times, thanks for your help on this matter so far and sounds like the MG dealer has some good advice.

Will report back!!!

 

[fred12345]

Tried uploading a photo from today’s drive:

59 miles from 7 of 8 bars, 2021 model doesn’t show percentage!!!!
3.8 miles per kwh
Range left is not showing so less than 10 miles remaining.
Going to slow charge and see what happens.

Will repeat four or five times, thanks for your help on this matter so far and sounds like the MG dealer has some good advice.

Will report back!!!

just remember not to stop charging for as long as the car is taking the charge, it will drop to less than 1kW whilst balancing ...

 

[Chris Law]

Post in thread 'ZS EV LR Will suddenly not fast charge'

Mar 2, 2026

2 things i can think of.

1. 2000 km in 4 days, all on CCS, could make the car derate the charging due to repeated CCS charges, which can be harder on the battery, the car will derate the charge speed to protect the batteries (Well to make sure they dont go below the warranty limit, to prevent them from having to give you a new battery)

2. Loads of CCS charges = Loads of "to 80%" charges = Batteries have not been balanced. If the battery balance between cells gets to high, it might limit the current to protect the batteries.

First thing to do is....Try sticking it on a...

• Chris Law

• 

Similar but not identical case where repeated granny charging mhelped