Discharged 12 volt battery

[siteguru]

On the MG3+ I don't know. On the MG4 the state of charge of the HV battery is shown (in %) on the driver screen and the Infotainment screen. The MG4 does not, however, show the current HV battery voltage.

 

[Coulomb]

Maybe you've misinterpreted my post?

Yes, I did. My apologies.

 

[Big Ears]

I notice on this forum we ask a lot of questions, but a lot go unanswered as there just isn't enough info.

 

[MG Clive]

There is a lug in the fuse box under the bonnet for jump charging, to save the hassle of getting into the boot.

So now that we're aware of this convenient lug for jump starting, does anybody know if it would also be possible to charge the battery in this way, rather than attaching a charger to the battery in the boot?

 

[Coulomb]

if it would also be possible to charge the battery in this way, rather than attaching a charger to the battery in the boot?

That lug has to have a high current (fat wire) connection to the auxiliary battery, so it will be fine for battery charging.

I used to use a similar lug for 12V charging in my Prius back when I owned one.

 

[MG Clive]

Thanks @Coulomb, that makes charging a little easier, if I ever need to?

 

[Big Ears]

Thanks @Coulomb, that makes charging a little easier, if I ever need to?

Have you got your power pack yet?

 

[MG Clive]

Have you got your power pack yet?

Yes I've got a power pack, I don't have a charger though. ?

 

[Big Ears]

?????????????

 

[MG Clive]

?????????????

Sorry mate, I don't understand?

 

[Big Ears]

You said you don't have a charger, mine came with one.

 

[MG Clive]

You said you don't have a charger, mine came with one.

What came with one, your power pack?

 

[Big Ears]

Is it me???

Sort of, it's part of the power pack it just has a USB A to C lead.

https://amzn.eu/d/ixiN6KJ

I think we may be at cross porpoises.

 

[MG Clive]

Is it me???

Sort of, it's part of the power pack it just has a USB A to C lead.

I'm talking about charging the 12volt battery in the car, well I was way back in Post #44.

 

[Big Ears]

I have never ever had a charger that was worth the trip to buy it, they seem to last for one or two charges then die on me, even more expensive ones, so I'm hoping the new tech will work around that and just start stuff.

 

[MG Clive]

This actually leads to another interesting question Kev, I wonder if we can charge the 12volt battery with our Power Packs? I'd think that as long as there's sufficient power in the Power Pack, it should put some of it into the 12volt battery.

 

[Big Ears]

Maybe a little short term but that isn't its job.

My thinking is to attach it, start it and if the car will take over and charge it, job done, if not then it will certainly (possibly) allow you to drive to get a new battery, assuming there is a safe place for it to sit for the journey and all unneeded stuff it turned off for the trip, the ignition system shouldn't take much.

 

[TonyD 2024]

If the 12 V battery is flat, then my understanding is that you use the power pack to get the ignition going, run the car for 30 minutes to put some charge back then limp home with minimum electricals running.

Once home trickle charge the 12 V battery in the boot with a full sized grown up charger that can assess is health at the same time. At this early stage in the battery’s life it should fine and not need replacing. The battery in my Golf lasted ten years and you soon know the end is nigh because it doesn’t hold a charge.

 

[Big Ears]

I also have a CTek ms5 smart charger, I keep one in the van and I have a spare as they are very much cheaper than a new battery.

 

[MG Clive]

Probably a silly question (sure someone will tell me) where is the negative terminal if using the fuse box method ?

There's a nice chunky bolt down by the front chassis leg to attach the negative lead for jump starting or charging. The terminals in the fuse box are NOT suitable as earth/negative connections.