12 volt battery

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Marquixanes

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MG ZS EV
I left my 70 plate MG ZS EV on the drive for 2 weeks and when I returned the car wouldnt open or start. Had to call MG assistance who quickly boosted the 12 volt battery and it then started. The AA man said MG supply a very small powered battery. Anyone else had this problem or has anyone a solution.
Brian
 
Do you have anything plugged in (to the OBD2 port for example)?
 
Marquixanes said:
I left my 70 plate MG ZS EV on the drive for 2 weeks and when I returned the car wouldnt open or start. Had to call MG assistance who quickly boosted the 12 volt battery and it then started. The AA man said MG supply a very small powered battery. Anyone else had this problem or has anyone a solution.
Brian
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its 12 volt the same as any other car! :O
 
there is a world of difference between 12 volt batteries. They are rated by the amount of charge they hold in Amps
[ Edit moderator: actually capacity is measured in amp·hours ]
 
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Most manufacturers put in a contract spec battery that even with a good name on it can be cheap and cheerful. It can be a good idea to just have a decent battery installed to remove future potential hassle. I did this after trouble with a top of the range Honda ICE vehicle A few years ago.
 
Any EV will have a lower AH battery than you'd find on an ICE car because it doesn't have to satisfy an engine cranking demand.
 
The 12v battery on any car shouldn't go flat in a couple of weeks, there may be something drawing a small current. On older cars the boot light switch sticking on would do it, on modern cars a "sentry mode" dash cam might be a problem, or one of the computers not shutting down.
 
I ended up with the big C just mid December on a Friday. Got home after the PCR test and parked up. Didn't plug it in as I didn't see the point. Went to plug it in on the following Sunday (day of release), and the car wouldn't open either... I had forgotten to unplug the dashcam. It was recording 24/7 and the 12v battery had gone down to 3.1V.

Couldn't charge it on the 12v trickle charger as it only raised it to 3.6V after 3 hours. Decided to jump start the car to open the charge port (could do with a manual release for that!) then plugged the Pod Point in and left it overnight. Once connected it kept the 12v alive to charge the main battery to drive to work the next day, even if the 12v was flat I could jump it and get the 12v replaced.

However, to my surprise the next morning the car unlocked, opened the bonnet and checked the 12v and it had been revived to 13.1v. happy I didn't have to spend nearly £150-£200 to replace the battery.

TLDR Don't leave the car for long periods with anything plugged in to the 12v (OBD or Dashcams).
Also remember to lock the car as it could still be "awake" (not sure but when i walk past it my phone connects!)..
 
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Marquixanes said:
I left my 70 plate MG ZS EV on the drive for 2 weeks and when I returned the car wouldnt open or start. Had to call MG assistance who quickly boosted the 12 volt battery and it then started. The AA man said MG supply a very small powered battery. Anyone else had this problem or has anyone a solution.
Brian
Click to expand...
I left my zs ev parked at the airport for 3 weeks in that really cold spell we had in December. Started fine on my return. Also the battery on the ZS ev is exactly the same battery that was fitted to the ZS ice I had previously.
 
Marquixanes said:
I left my 70 plate MG ZS EV on the drive for 2 weeks and when I returned the car wouldnt open or start. Had to call MG assistance who quickly boosted the 12 volt battery and it then started. The AA man said MG supply a very small powered battery. Anyone else had this problem or has anyone a solution.
Brian
Click to expand...
Haven't had a flat battery but ensure we don't leave anything drawing current (OBD or dash cam) for any length of time. Suggest you grab a lithium jump starter as a backup. They are reasonably cheap, hold in ya hand and perfect to get you mobile again.
 
I see a few of you mention dash cams. When I asked MG I was told it would cost £500, does anyone know of a cheaper recommended model?
 
Sue H said:
I see a few of you mention dash cams. When I asked MG I was told it would cost £500, does anyone know of a cheaper recommended model?
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Mileage varies on what's classed as a recommendation, but I have a couple on a shortlist and will likely go with the second one as it best suits the requirements I have, at a reasonable price.
There are also lower res versions as well as plenty of other makes depending on what you want:

-Thinkware U1000 4K

-Viofo A129 Pro Duo 4K

Amazon product ASIN B07RXPP143

The Duo version of the latter was fitted to a ZS EV here, and around the 1:11 mark there's footage:




For more sample images, I don't think there's a channel does better side by sides:

 
Elec Car Aust said:
Haven't had a flat battery but ensure we don't leave anything drawing current (OBD or dash cam) for any length of time. Suggest you grab a lithium jump starter as a backup. They are reasonably cheap, hold in ya hand and perfect to get you mobile again.
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I use a halo jump starter not the cheapest but will charge my iphone/ipad thro usb ports and has a pump fitted which i thought might be weak but blows the tyres up brilliant ,used it 3x on next doors car and only used 4% of the charge it holds..
 
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My 12v battery went flat a few times when new, never found the reason, starting behaving by the time I had read the instructions.
I made a short video of me checking the 12v charger with a volt meter in the cigar lighter.

I have a new Bosch battery, I will change it at sometime, Bosch silver line lasted 15 years on my Vectra.
 
micky said:
I use a halo jump starter not he cheapest but will charge my iphone/ipad thro usb ports and has a pump fitted which i thought might be weak but blows the tyres up brilliant ,used it 3x on next doors car and only used 4% of the charge it holds..
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I think I have the same Halo unit !.
 
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