MG ZS EV - Faults cannot drive...

[Kithmo]

Or the brake light switch is duff.

 

[Evlife]

I had the same issue a month ago aa took car to dealer who said bms was out of date had all updates done to car but still having to slow charge car to equalise battery battery because car still saying please slow charge battery . Don’t know how long i have to do this before i can use my 7kw home charger .

 

[JCFlippen]

I think 7kw charger is a slow charge as I’m pretty sure manual says balancing can be with granny or 7kw

 

[Evlife]

I was told by garage to use only granny .

 

[Cocijo]

You can granny or 7kw ac to equalize the battery pack.

 

[Evlife]

I've been equalising battery now for over three weeks but every time I Stert car it says please slow charge battery is this normal ?.

 

[JCFlippen]

Deep down the dealer should sort this out and give you a courtesy car until process is completed.

 

[Cocijo]

I've been equalising battery now for over three weeks but every time I Stert car it says please slow charge battery is this normal ?.

What HV pack voltage do you get when fully charged? If on latest bms should be 450v the further you are from that the longer it will take to recover. If it’s a good way from 450v the dealer should sort it and give you a car to use while they do.

 

[Evlife]

I've just checked car volts saying 431 badge lights on solid car saying 98 percent charged 2 minutes left. Unplugged car and plugged back in badge lights still permanently on but car says charging complete. Do I leave it plugged in until badge goes out ?,

 

[Evlife]

Car is now saying 98 percent 2 mins left badge still solid on .

 

[Chrispydoc]

I believe a solid lit badge means its balancing the battery cells...mine sometimes sits like that for hours...I just leave it plugged in.

 

[JCFlippen]

Leave it connected till light goes out. Balancing finished when badge goes out. Should have 449 or 455 depending on BMS version unless others know different.

 

[Cocijo]

Leave it connected till light goes out. Balancing finished when badge goes out. Should have 449 or 455 depending on BMS version unless others know different.

Unfortunately no. It can take a long time to build back up to the top voltage depending on how badly your cells are out of balance. It will take many balances if voltage fully charged is showing c430v. That’s why i suggest the dealer does it unless you have lots of patience. ?

 

[Evlife]

OK I will leave it plugged in until badge goes out and granny charger charge lights flash .
Thanks to you all for advice mg dealer not very helpful .

 

[Evlife]

Luckily I'm retired so dont use car everyday when badge goes out I will go for a Sunday drive then slow charged again .

 

[JCFlippen]

If the car is new then it really is a problem for the dealer to sort.

 

[Evlife]

My dealer told me just to keep running battery down and slow charge car . To be honest my dealer not very good and service team are still learning zsev issues. Even AA recovery they still don't know what causes issues with eV cars

 

[Cocijo]

My dealer told me just to keep running battery down and slow charge car . To be honest my dealer not very good and service team are still learning zsev issues. Even AA recovery they still don't know what causes issues with eV cars

I’m sorry you’re having issues And hope that you get it sorted. You only need to run the battery down to about 90% before charging and balancing (not sure if the dealer told you this). The dealer has updated your bms to the latest version haven’t they? You are perfectly fine using your 7kw charger to balance. You should see the fully charged voltage move up after each full balance.

 

[Michael Holt]

My dealer told me just to keep running battery down and slow charge car . To be honest my dealer not very good and service team are still learning zsev issues. Even AA recovery they still don't know what causes issues with eV cars

I'm sure I read somewhere that it can take up to 30 of these rebalancing charges to rectify the problem. If this is not the case I'm happy to be corrected if someone knows differently.

 

[Cocijo]

each balance cycle will balance by a certain amount ( i believe 0.1v). So 10x balances will lift by 1v. If you're low by 20v it can take 200 balances to get back to normal. this is from memory - It‘s been a while since I looked at these numbers. This is why on the very unbalanced packs the dealer needs to do the work and supple a car.