12V battery drained in 48 hours whilst locked

Good on-ya fella, interesting background mate, any convicts or Vandemonians in the family Terry?
:ROFLMAO: :unsure: (y)

I totally agree with all you say about new arrivals to our country Terry and not speaking the language, we have loads here, they normally work as delivery van drivers and throw our parcels into a neighbour's garden or just sell the whole f***** van load on a well known auction site.
No convicts or two headed relatives, though the wife has a brother with a 100 acre block perched on the side of the Huon near the top .... Not the end of the world, but you can see it from his front verandah :LOL:

T1 Terry
 
Luckily, I don't know any Americans. 😵‍💫
The neighbour is trying desperately to lose any accent, says he is from some island or another but glad he escaped the place ..... can't believe how friendly everyone is in Australia ..... I told him it's probably because you don't talk like a yank, nothing to do with accents, all to do with not thinking everything is better in the USA ....

T1 Terry
 
Good on-ya fella, interesting background mate, any convicts or Vandemonians in the family Terry?
:ROFLMAO: :unsure: (y)

I totally agree with all you say about new arrivals to our country Terry and not speaking the language, we have loads here, they normally work as delivery van drivers and throw our parcels into a neighbour's garden or just sell the whole f***** van load on a well known auction site.
At least they are working and paying taxes (for the most part) unlike our own work shy benefit dodging feckless under class that our half wit government keep rewarding with extra benefits and reasons not to look for work
 
The government is pumping millions of pounds into trying to stop the illegals from coming to the U.K. and handing out millions to prevent them crossing the channel.
None of this is working with any great susses of course.
If you want to stop ✋ the invasion quickly and cheaply, the answer is simple.
STOP ✋ paying them all of this money, and they will soon stop coming.
 
The government is pumping millions of pounds into trying to stop the illegals from coming to the U.K. and handing out millions to prevent them crossing the channel.
None of this is working with any great susses of course.
If you want to stop ✋ the invasion quickly and cheaply, the answer is simple.
STOP ✋ paying them all of this money, and they will soon stop coming.
Send some of our feckless on boats to France in exchange, that will motivate the French to help
 
Yet another update, are we getting somewhere? Just maybe.

Several voltage readings and tests on my S5 12v battery over the past week or so.

Now then I don't exactly suspect the 12V battery is faulty here, as it held up well whilst the negative lead was disconnected for 24 hours @ 12.85 Volts. BUT it likely is causing the issue due to it's puny capacity, see below!

As soon as I reconnected the battery I regularly watched as it had gradually slipped by this morning to 11.78V after 48hrs with lots of regular readings, with NO use & NO charging (remained all the time in a cavity wall garage) cold but not below freezing or as cold as leaving it outside.

I collated the readings, hand delivered to Penton MG Salisbury this morning, they are great, very responsive and helpful, as we all know, it's MG HQ which are the holders of the purse strings as I'll mention shortly.

An appointment and a loan car is booked for Wed 14th Jan, possibly for several days.

But my thoughts are the 35Ah battery is just NOT man enough to cope with the demands of a very cold British winter weather, using heating, demisting, heated seats and steering wheel etc etc.

Why the F*** should we go without the niceties we've become used to in modern cars, like heated seats etc as mentioned above, because MG fitted a crappy "not fit for purpose" 12v battery, IF nothing can be found at fault during the garage visit next week.

Penton MG service department have tried to find a replacement battery for another S5, but NO LUCK, of course not, it not much bigger than a bloody motorbike battery, I've found several of a similar physical size but double the capacity with 70Ah, I'm tempted to just buy one, but I should NOT be replacing anything on any new car because it's not man enough, FULL STOP.

I was told there are only 5 people in the MG HQ tech department answering queries not only ALL of UK's queries, but they also look after Europe as well, no wonder we all think they are not interested in us consumers, they are simply rushed of their little arses.

Cheap car = cheap backup.
 
Yet another update, are we getting somewhere? Just maybe.

Several voltage readings and tests on my S5 12v battery over the past week or so.

Now then I don't exactly suspect the 12V battery is faulty here, as it held up well whilst the negative lead was disconnected for 24 hours @ 12.85 Volts. BUT it likely is causing the issue due to it's puny capacity, see below!

As soon as I reconnected the battery I regularly watched as it had gradually slipped by this morning to 11.78V after 48hrs with lots of regular readings, with NO use & NO charging (remained all the time in a cavity wall garage) cold but not below freezing or as cold as leaving it outside.

I collated the readings, hand delivered to Penton MG Salisbury this morning, they are great, very responsive and helpful, as we all know, it's MG HQ which are the holders of the purse strings as I'll mention shortly.

An appointment and a loan car is booked for Wed 14th Jan, possibly for several days.

But my thoughts are the 35Ah battery is just NOT man enough to cope with the demands of a very cold British winter weather, using heating, demisting, heated seats and steering wheel etc etc.

Why the F*** should we go without the niceties we've become used to in modern cars, like heated seats etc as mentioned above, because MG fitted a crappy "not fit for purpose" 12v battery, IF nothing can be found at fault during the garage visit next week.

Penton MG service department have tried to find a replacement battery for another S5, but NO LUCK, of course not, it not much bigger than a bloody motorbike battery, I've found several of a similar physical size but double the capacity with 70Ah, I'm tempted to just buy one, but I should NOT be replacing anything on any new car because it's not man enough, FULL STOP.

I was told there are only 5 people in the MG HQ tech department answering queries not only ALL of UK's queries, but they also look after Europe as well, no wonder we all think they are not interested in us consumers, they are simply rushed of their little arses.

Cheap car = cheap backup.
The thing is if the battery isn't fit for purpose them just about every car should be experiencing the same issues you are and they aren't
 
As soon as I reconnected the battery I regularly watched as it had gradually slipped by this morning to 11.78V after 48hrs with lots of regular readings, with NO use & NO charging (remained all the time in a cavity wall garage) cold but not below freezing or as cold as leaving it outside.

I can relate to these figures, to some extent (details below).

Since my series of 12v battery failures and consequent use of a booster pack, along with the fact that a two-day diagnostic check by my local MG dealer failed to find any fault, I have been quite studiously checking the state of my battery at least once per day and collating the results to give to the dealer when the car goes in for further diagnostic checks tomorrow and Wednesday.

The following are some of the results (and I think you will see what I mean by my earlier comment of some extent of similarity):
  • Following the use of a 12v battery charger, the voltage, recorded as "Full" on the charger, was 12.8v
  • Over the next approximately 7 days this gradually fell as low as 12.0.
  • The day after the 12v result, the figure, with the car fully "off" read 14.7!!
  • The next two readings were 12.3.
  • Every day since January 1st the readings have been 14.7 or 14.8, still with the car definitely "off"!
It would seem that the "Intelligent Battery Charging" is doing something at least! And I obviously haven't needed the battery booster again since December 22nd.
The thing is if the battery isn't fit for purpose them just about every car should be experiencing the same issues you are and they aren't.

Quite so! And if my results listed above are anything to go by, the reason for this "flat 12v battery problem with the MGS5" is likely to be very difficult to diagnose and correct.
 
It would seem that the "Intelligent Battery Charging" is doing something at least! And I obviously haven't needed the battery booster again since December 22nd.
Where is the Intelligent Battery Charging option? Or is this something the MGS5 offers that the MG4 doesn't?
 
According to the MG4 Manual, keeping the 12V battery charged is 'intelligent'.

Screenshot_20260105-203722.Moto App Launcher.webp
 
Well I suppose it is as it would be stupid to let it go dead🤔
But "going dead" was exactly what happened to me last week Len, with the car garaged and turned off and nothing running for 48 hours, that is what this thread is all about!!

Irrespective of any excuses or reasons why, no modern car should self flatten the battery if unused for this short time, my previous MG4 at least 3 times in 2 years for nearly 4 weeks without a problem.

So my conclusion has to be either a parasitic drain or inadequately sized 12V battery, unable to cope with the rigors of a very cold snap and a wife who needs more heat than most . :ROFLMAO::ROFLMAO:

Hopefully MG will be able to sort it one way or the other! 👊🫰
 
Well, Caliban is now in his garage at 69% charge with temperatures rapidly heading for the minus department. I'll let you know in a month how that works out. Since the garage is locked and the keys are inaccessible, I've left the car unlocked just in case.
 
So my conclusion has to be either a parasitic drain or inadequately sized 12V battery, unable to cope with the rigors of a very cold snap and a wife who needs more heat than most . :ROFLMAO::ROFLMAO:

Hopefully MG will be able to sort it one way or the other! 👊🫰
My conclusion would be that the "intelligent charging" isn't working. No matter the capacity of the battery, if it's getting charged when needed, there shouldn't be a problem.

Is this because the HV battery isn't full enough, or is there another fault?
 
My conclusion would be that the "intelligent charging" isn't working. No matter the capacity of the battery, if it's getting charged when needed, there shouldn't be a problem.

Is this because the HV battery isn't full enough, or is there another fault?
That is another point I've already put to my local MG garage @decrep, in my case the 12v battery suddenly went flat, now I don't know if it was a gradual decline which was unnoticed or a complete failure of something, possibly due to the battery management system, but whatever the cause it appeared without warning.
 
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