Dead (12V battery) on arrival! less than auspicious start

[drjas]

My wife and I picked up our brand new MG ZS EV from the dealer last Wednesday (24th) lunch - oh happy day! A few afternoon errands, then my wife was driving out to a post-COVID dinner gathering when the computer spat the dummy, shouted a range of alarms and then shut down the car. She was fortunate the road was not to busy and she was able to pull off the road onto a relatively flat platform. But with no 12V battery she could not put the car in park nor activate the parking brake - fortunately a friend was able to come with a brick to stop the car rolling when she lifted her foot from the brake.

Then proceeded a rigmarole to call out roadside assistance to verify the 12V battery was completely flat, another wait for a tow back to the dealer, and calls and queries to figure out what is going on? There's clearly both a physical and a computer problem.

By Friday the dealer workshop determined that the 12V battery is dead, and MG tech support instructed ordering a new one, which might turn up tomorrow. Then we need to be convinced as to why the rate of discharge exceeded the 12V charging. Need to find a way to fall in love again (with the car ).

MG are now saying there's a batch of faulty batteries - curious to know if anyone else has come across the like?

We're also new to electric parking brakes - interested to learn from others' experiences like this?

 

[Gomev]

Good to know we are post-Covid and dinner gatherings are allowed in Aus. We are a little way behind.
Good luck with the diagnosis, I'm sure it will be something simple.

 

[bloggsy]

Oh crap! I'm waiting to pick up my wife's brand new ZS EV - hope it's not one of those affected by the faulty battery Are there any warning signs before it goes into 'meltdown'?

Cheers

Bloggsy

 

[drjas]

Some idiot lights and messages to drive the car to charge the battery (which was happening). But if there is a fault with the battery it shouldn't really pass through pre-delivery workshop inspection.

 

[JodyS21]

I'm going to offer a guess here.

When the car is in Ready mode (i.e. it is running/on), the High Voltage battery should keep the 12V battery topped up. When this is occurring, the voltage reading on the 12V battery should read about 14V (as it's being charged).
If it's not reading about 14v (above 12V) - bottom gauge on left dial, then it's not charging it up and it's going to run downnnnnnnn and game over.

 

[TassiedEVil]

Some idiot lights and messages to drive the car to charge the battery (which was happening). But if there is a fault with the battery it shouldn't really pass through pre-delivery workshop inspection.

What a shame and I’m feeling your disappointment. I hope it’s resolved in the next few days and you can make a new start. As for an emergency parking brake : I’m going to put a brick in the car ... or maybe a case of beer...

 

[Cocijo]

Some idiot lights and messages to drive the car to charge the battery (which was happening). But if there is a fault with the battery it shouldn't really pass through pre-delivery workshop inspection.

It’s a hangup from ICE that you have to drive the EV to charge the battery. When the HV battery is engaged ‘ready’ it charges the 12v battery - there’s no need to drive anywhere.

 

[Cocijo]

When the cars are shipped there is a transit switch used on the 12v battery allowing switching on and off during shifting the cars around etc from outside the cars - sometimes the 12v batteries can get run right down and this can lead to a failure later on down the line.

 

[Chrispydoc]

It doesn't look good.....so much for the PDI!

 

[Kithmo]

ISTR someone mentioning a loose battery connection on one.

 

[micky]

What a shame and I’m feeling your disappointment. I hope it’s resolved in the next few days and you can make a new start. As for an emergency parking brake : I’m going to put a brick in the car ... or maybe a case of beer...

make it several cases of beer you might have a wait for the tow truck..

 

[Lovemyev]

It doesn't look good.....so much for the PDI!

What PDI ????.
Number plates fitted, charge the HV pack and ship it, that is my guess !.
Back in the day, at the large dealership where I once worked, the service department use to charge the sales department a flat rate of .5 of an hour ( 30 mins ) to PDI the car, then another .2 of an hour ( 20 mins ) to fit the number plates.
That was it !.
Then it went over to the valeting department to make it look nice and shiny.
I once remember having a Triumph TR6 fuel infection to PDI that would not even run correctly.
I turned out the engine did not have a head gasket fitted between the engine block and the cylinder head !.
How the hell they got it out of the factory I have no idea !.
Hard to believe I know, but totally true.
I have seen some things that would shock you !.

 

[Dave53]

U

I'm going to offer a guess here.

When the car is in Ready mode (i.e. it is running/on), the High Voltage battery should keep the 12V battery topped up. When this is occurring, the voltage reading on the 12V battery should read about 14V (as it's being charged).
If it's not reading about 14v (above 12V) - bottom gauge on left dial, then it's not charging it up and it's going to run downnnnnnnn and game over.

When my car is sitting idle not on ready if I leave the infotainment system on listing to the radio etc. It switches off automatically after a time, I'm not sure if it automatically switches off anything else but I need to switch off the car and start it to ready to bring the system back on, there must be some system that recognizes the 12v system is being drained if I have it sitting on ready it keeps on playing for as long as I like, my old ice car did this as well it had to be running for it to play for any length of time.

 

[drjas]

Update: the dealer has reported the car drained a new 12V battery in less than 6 hours (between installing mid-morning and calling us before COB). So something drastic is draining the battery.

 

[Cocijo]

U

When my car is sitting idle not on ready if I leave the infotainment system on listing to the radio etc. It switches off automatically after a time, I'm not sure if it automatically switches off anything else but I need to switch off the car and start it to ready to bring the system back on, there must be some system that recognizes the 12v system is being drained if I have it sitting on ready it keeps on playing for as long as I like, my old ice car did this as well it had to be running for it to play for any length of time.

It’s always best to have the car in ready if you’re sitting using any accessories - it keeps the 12v charged. I really don’t see the point of having the 12v only setting - it serves no purpose.

 

[Paulie68]

What PDI ????.
Number plates fitted, charge the HV pack and ship it, that is my guess !.
Back in the day, at the large dealership where I once worked, the service department use to charge the sales department a flat rate of .5 of an hour ( 30 mins ) to PDI the car, then another .2 of an hour ( 20 mins ) to fit the number plates.
That was it !.
Then it went over to the valeting department to make it look nice and shiny.
I once remember having a Triumph TR6 fuel infection to PDI that would not even run correctly.
I turned out the engine did not have a head gasket fitted between the engine block and the cylinder head !.
How the hell they got it out of the factory I have no idea !.
Hard to believe I know, but totally true.
I have seen some things that would shock you !.

I can believe that, it was most likely on purpose. Back in those bad old days, workers would do lots of malicious stuff. Another favourite was putting random nuts and bolts loose in the bottom of the doors to cause rattles. Often left over sandwiches from lunch were thrown in as well. Hard to believe today, but car factory workers were an angry lot back then.

 

[Dave53]

It’s a hangup from ICE that you have to drive the EV to charge the battery. When the HV battery is engaged ‘ready’ it charges the 12v battery - there’s no need to drive anywhere.

I wonder if the electric system likes being left in ready and not going anywhere? I have no idea what the state of the car/electric motor is in when in ready mode or what is drawing electricity at that point but it does drain the HVB even with the heating/aircon off etc.

 

[Cocijo]

I don’t think it does anything other than engage the HV battery pack which keeps the 12v topped up to run accessories. It does draw from the HV but there’s plenty to go around compared to using the 12v alone Some EV’s just go straight to the HV battery being engaged on start up. As I’ve suggested the 12v position is really quite pointless in my opinion. There is no real difference between sitting parked in ready state and driving other than of course once you select D or R and move off you use the HV pack to turn the motor that powers your movement - and you get regen of course under certain conditions

 

[Cocijo]

I can believe that, it was most likely on purpose. Back in those bad old days, workers would do lots of malicious stuff. Another favourite was putting random nuts and bolts loose in the bottom of the doors to cause rattles. Often left over sandwiches from lunch were thrown in as well. Hard to believe today, but car factory workers were an angry lot back then.

I love the left over sandwiches in the door thing! I wouldn’t of course if I found one in mine!

 

[Gomev]

I don’t think it does anything other than engage the HV battery pack which keeps the 12v topped up to run accessories. It does draw from the HV but there’s plenty to go around compared to using the 12v alone Some EV’s just go straight to the HV battery being engaged on start up. As I’ve suggested the 12v position is really quite pointless in my opinion. There is no real difference between sitting parked in ready state and driving other than of course once you select D or R and move off you use the HV pack to turn the motor that powers your movement - and you get regen of course under certain conditions

I think this video from Bjorn Nyland demonstrates your point well