Replacement 12V auxiliary battery for MGS5

I have setup a card in Home Assistant to monitor my S5:
1770379698103.webp

As you can see it does monitor the Aux battery (voltage) so the data is available?
 
how do you do this? I am familiar with HA, not an expert but I imagine you need HACS and your card may be custom
Yes exactly that - the setup involves a 2nd user for the MG app logon (as only one logon per user at once) and chat gpt walked me through the steps AND suggested the card to use and it worked a treat (obviously you can choose what info you want to display)
 
Brilliant news on my S5 12v auxiliary battery, after being sat at Gatwick airport for three and a half weeks and my previous experiences of it going totally flat.

Despite my fears, it survived and started the car perfectly on our return last night 17th Feb.

I've now got restored confidence in my MGS5, all the hassle was down to fitting permanent live a dash cam, sounded a good idea at the time, but thinking about it, the number of times a car is going to get a bump whilst parked and asleep must be pretty minimal.

So this is a warning to all thinking of being a smart arse like me, fitting a dash cam with permanent live monitoring, the puny 35Ah12v battery cant cope with any more than a few days idle without causing grief and flattening the battery.

BTW my dash cam is a Viofo A229 Plus, other brands may not draw as much standby current, it would be interesting to know if others have similar problems with their dash cams.
 
My issue was that the gateway module was staying awake and draining the 12v battery. Let's see if I have anymore issues over the next few weeks
That follows on with the theory the phone being so far away from the vehicle, Bluetooth couldn't keep waking it up .....

T1 Terry
 
So this is a warning to all thinking of being a smart arse like me, fitting a dash cam with permanent live monitoring, the puny 35Ah12v battery cant cope with any more than a few days idle without causing grief and flattening the battery.
I have successfully installed the Blackvue front and back dashcam connecting to a external Blackvue battery (see photos) which is connected to the 12V cigarette plug permanently in the middle compartment. Contrary to popular belief, this outlet isn't permanently on, as I have the Blackvue battery app that confirmed the supply is off as soon as the car is off. I had this system connected this way for couple of months now, and I have never depleted the external 12V battery. The only catch is to fit a toggle switch between the camera and battery, so as soon as I'm home I can turn off the camera system. Otherwise it will deplete the Blackvue battery overnight. This battery system can maintain the camera in recording mode whenever I'm out and about for security purposes.
 

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