Content by Joningy in January, 2026

So from this can we positively say the High voltage traction battery is definitely charging the auxiliary battery when it drop to or below 12.3 volts? Knowing if this is correct, helps when my car goes in for diagnostic checks on Wednesday, I also suspect the charging system is possibly faulty...

That is a new and very interesting approach, but if MG is capable of the 12v auxiliary battery being topped up from the HV traction battery whilst locked and asleep, why isn't it? This leads me to think perhaps, what I was told that MG does NOT support this is correct, I'm thoroughly confused...

Yes they did a pretty good deal for us on Hyundai, but since I've got the Excellent Penton MG just a few miles away in Salisbury, I don't need to travel all the way to Pompey, unless of course they do a better deal one day :unsure: :ROFLMAO: (y)

Sounds like you'll be doing a similar thing to me on our 2 year interest free deal MG4, chuck it back to the finance company, they wanted 4 grand more than the car was worth @Black estate . Bought MGS5 in Sept, a tad over 24 grand cash in Sept. I guess your local MG is Richmond, I bought my...

My MG44 gave no problems during the 2 years I had it, never a problem leaving the car parked for 4 weeks at Gatwick Airport @tsedge My current S5 is different, the battery problem happened recently, not from the, sobvostart, so something somewhere has recently failed, I think the battery is...

Just as I reckoned it may be Martin, I'm not sure where the info comes from, as it's not easy to find some things at times which AI does!

An important thing to remember @marcbesty , storing your 12V booster is crucial, NEVER keep it in the boot as its very difficult to access when the 12V is down, I used to keep it under the seat, but it did slip out occasionally, now I keep it on the shelf, under the centre console, after reading...

Hi again Terry, thanks again. My DIY solar storage battery bank is the flooded lead acid type you refer to, i.e. colossal thick plates, each 2v cell weighs 50Kg, I have a bank of 24 of the heavy sods, very difficult to manoeuvre, but solid performance.

Yep there are several threads on this forum, I've detailed parts of the installation of my thread back in September. I've also hard wired to a permanent live fuse, all cables neatly tucked behind the head lining. VIOFO A229 Plus: Dual 2K HDR front + Rear

Sounds like the same issue as I have @marcbesty . I was told a similar thing: "MG expect the car to be driven more often" what a load of b******s, Don't stand for it, keep pushing. Not sure how much you've read of this was my thread on the same subject. 12V battery drained in 48 hours whilst...

Thanks @Lovemyev @emmrecs @siteguru & @Martinonline and all other contributors. It may well be the charge controller, but it certainly charges the auxiliary battery, during HV charging, it also works correctly whilst in "ready" or drive mode, it certainly is NOT charging whilst switched off and...

The car was charged to 80% 2 days ago and was still the same this morning @siteguru , but in that time the battery drained to 3v, parked in the garage. So there's either a serious parasitic drain, or IF the HV battery is supposed to monitor & charge the auxiliary battery whilst asleep, then...

12v battery down to 3v again this morning (09/01/26) Phoned local Penton MG, because this points towards the HV battery not charging while the car is in switched off, I was told this is correct. I was under the impression the HV battery did charge, so long as the the HV battery SOC was above...

@Ian Key My Armrest Storage Box & Center Console Lower Storage Tray, from Ali Express turned up yesterday Ian and fitted (perfectly) today, the armrest is by far the more useful, but both delivered in a week from China , both for £12.49p, including all delivery costs, pick up in China, flight to...

I fully understand what you say Terry, well not actually fully @T1 Terry 'caus I'm unable to correctly diagnose it, I don't have anywhere near the correct test equipment, I'm hoping Penton MG does! But I'm personally kinda pointing towards the possibility of some form of charging malfunction...

Snow chains work incredibly well, I've used them in the Alps!

That'll be fine, I'll pop in and video it at the same time, YouTube may recover the repair cost 😂😂 The days when we were able to repair the cars ourselves! No abs on the ole bus either. :ROFLMAO:

Well done Ian, have you tried it lately? imagine the neighbours faces if they were watching it. ;):ROFLMAO:

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...

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 opinion is RWD has many benefits over Front WD, having experienced powerful front wheel drive torque steer and other negative attributes, I'd much prefer RWD or 4WD over front wheel drive. Snow for us in the south is a rare occurrence, so it would not be in any way a decision factor in...

Yes as @Ian Key mentioned above, he and I and presumably lots of others with S5's found it very good indeed.

I did exactly the same today Ian, worked extremely well, but not until I tried to stop at a local road junction and kept going, nearly needing fresh undies. :ROFLMAO:

I thought the same thing Clive, But I'd guess most comms would be by email, if that's the case, Google Translate or similar would be widely used. But if a telephone call is required then as you say, language may be a problem, but wherever we go now, virtually everyone uses English. As I've...

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 we consumers, they are simply rushed of their little arses All through MG keeping trying to...

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...

I remember someone who boasted 6 or 7 miles per kWh on this forum, even posted a photo, we can all do that if we zero the reading and freewheel down a hill as @Everest suggested. 😂

A lot of people are using those new fangled "tuned" calculators from China 😂

Yep that's about it and what most are doing, plug it into the charger set to 100% plus a bit, wake up, all done! 🤞🤞🤞

Or cabling There is loads of routing info on the net, just look at EV routing maps, it'll bring up lots of info and hopefully not yer breakfast through worrying :unsure: :ROFLMAO: size

I used to be on that tariff, and often charged the car and ran household appliances during the half hour slots, but things changed and those slots became fewer, so I switched to Intelligent GO, now I don't have to keep a look out for the cheap slots, it's every night at a steady 7p, OK its...

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...

I agree with everything you say except in your 4th paragraph- Do you actually mean 2 hours AFTER the charge has reached 100% to balance the cells, or do you mean something else? There has been so much talk on this forum regarding balancing or equalisation as it is often referred to and a lot of...

As a matter of fact @T1 Terry, with the surname of Ingram, although I don't have the accent, there's a strong connection to the Colquhoun clan in the Dunbartonshire region of Scotland, north west of Glasgow. :ROFLMAO: :ROFLMAO:(y)

My note to Penton MG hand delivered this morning. "I understood that the main battery is meant to kick in and charge the 12V battery when it drops, even if the car is 'off', is this correct? if so, what is the minimum HV traction battery SOC to achieve this? I’ve read 20 to 30% or possibly as...

@Lovemyev That is a bright idea, I had thought of making something to fit the small key, to enable a better grip and ability to turn the key, but I'll look at your suggestion, firstly I'll see what room is available to turn the key, it only needs a small movement, but of course the door doesn't...

Yes that's a possible solution Ian 👍

Thanks Ian,, as I thought, it all helps @Ian Key

Yes I use the MG i-smart app @Shwd mae , but never had a problem with it logging out and needing to re install it or anything, I don't think its overly slick mind you.

Ian, was your ICS problem only a charging problem? did the 12V battery ever loose power and drain? I'm asking as I'm tying to eliminate potential red herrings on my sudden battery failure after running apparently well for 2.5 months. Thanks for your help and input @Ian Key

I guess being a mechanical engineer in R&D for the early part of my life made me inquisitive. I'm now retired and beyond inquisitive if I get my teeth into something, thanks to all for their support and recommendations, this is a great forum and I still love my S5 to drive. My immediate...

Thanks @Lovemyev , just popped up the garden to the garage (7pm), the CTEC_7 charger is on prog. 7 (float) so I'll unplug at 8pm and check the voltage after resting for an hour after 9pm, that should give me at least a good indication of voltage. I'll then leave the battery disconnected to the...

Update progress. My S5 12v battery dropped from 12.5v to 12.4v overnight after disconnecting the negative lead for 12 hours, this is a kind of expected figure I guess, given the car was "warm" on our return at 10pm last night and close to zero Celsius this morning, so perhaps the battery is...

I guess @Martinonline is referring to the SOC % required to charge the Aux 112v battery from the traction (HV) battery, I seem to remember somewhere reading reading that the "sufficient" figure is 20 to 30% from memory, although 50% sounds more likely! The auxiliary battery on the new MGS6 is...

Try looking at the IM section of this forum Terry, there's a recent chat about the auxiliary 12v battery, https://www.mgevs.com/attachments/im6-battery-webp.42252/ this may answer your question @T1

I'm now wondering if this may have caused my initial battery drain, but now I've removed it, I don't think it's cured the problem @Alb I'm () This demonstrates the importance of a separate 12V Car Battery Booster, Portable Power Bank & combined Jump Leads, although we should NOT be needing to...

I've recently learnt MG IM range, as they are called here in UK, also use lithium auxiliary batteries. I guess the breakdown companies are equipped with the kit to deal with it worldwide today.

Follow up on my flat 12v battery, since getting home from Penton MG with a fully charged 12v battery, like @emmrecs I'm checking the 12v battery, every day, sometimes 2 or 3 times per day and recording the readings. this morning (new years day) the reading was 11.6 volts. A measurement of 11.6...

I like Sam Evans, I follow his You Tube channel, but he does waffle on at times, constantly repeating various points, as in this clip, to the extent that I fast forward a lot of them.