MG5 12v Battery Replacement Cost?

HoriUK

HoriUK

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Evening all. Looks like this cold weather has done for our 12v battery - after a week of the infotainment playing up, today the car was totally dead.

Our neighbour kindly (especially as the AA aren't responding to homestarts today) gave us a jump, and when it came back to life I think it went though every warning it's got! Annoying, as when I looked yesterday it was reading 14.5v (now 13.7v).

Anyway, as our car is now a whopping 14 months old it looks like we'll have to cough up for a replacement - anyone know how much the dealers charge for one, or what regular battery size fits? Cheers.

12v battery.jpg
 
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It is not that unusual for the vehicle manufacturers to limit the 12v battery to 1 year warranty, it is classed as a consumable component. When component manufacturers offer an extended warranty it is the component manufacturer that is responsible for that warranty not the company that used that component. I bought a TV with a 5 year warranty, I could not claim for new batteries in the remote.
 
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Hairyfool said:
It is not that unusual for the vehicle manufacturers to limit the 12v battery to 1 year warranty, it is classed as a consumable component. When component manufacturers offer an extended warranty it is the component manufacturer that is responsible for that warranty not the company that used that component. I bought a TV with a 5 year warranty, I could not claim for new batteries in the remote.
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If the remote runs out of battery you can still walk up to the TV and use physical buttons…
 
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Alb said:
13.7V will not be the battery voltage, it will be the charger voltage.
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Take heed to this folks!! If you put a meter across the battery whilst connected to the car, your reading the voltage being fed to the battery from the charge controller.
To check and test properly, it should at the very least be disconnected from the car.
 
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Surly when the car is FULLY powered down, the 12 volt battery should be displaying its standing / idle state, otherwise if it was displaying power supplied from the charge controller you mention you run the risk of draining the battery via a phantom drain ?.
A disconnect is always a good idea, but easy enough to prove.
Take a reading with a volt meter with the battery connected, then disconnect one of the battery terminals and recheck the voltage then.
 
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You would think with all the advancements in EV battery technology some of that science would be incorporated into 12v batteries. Sadley no. My previous ICE car had 3 batteries in a 2 year period. The last one had a 5 year 'guarentee' when it gave up after 18 months. It failed the criteria for replacement because it still had some charge in it.
I was also told by the garage that battery 12v manufacture is rubbish now and there is no point getting a 5 year warrenty.
Hope yours is fixed soon.
 
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If you turn power on but don’t press the brake pedal to connect the HV battery (which charges the 12v battery) the dash displays the 12 volt battery voltage. This will start at about 12.8 which is the nominal voltage with no charge/discharge, and then it will drop fairly fast to about 12.1/12.2 because the battery is supporting all the 12 volt loads which are quite large. Lead acid battery terminal voltage is dependant on state of charge, rate of charge or discharge and temperature. There are some good graphs of all these factors on the internet.
 
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Most do have buttons that give rudimentary control but they're normally placed in a very unobtrusive location (often behind the screen).
 
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So Kithmo if you read you tv instructions it will tell you where your buttons are or get the model number of the back and google it you never know if your remote control goes up the creek you will be stuck.
Somewhere there will be a master on/off button and probably a volume up&down buttons must be but if it’s an MGnisee model Maybe not in that case then I suggest opening up a new thread on the forums lol
Les
 
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The nominal at rest fully charged voltage for a lead acid car battery is 12.6-12.7 volts, the measurement has to be fairly accurate as the difference between full and 50% (the lowest you should take one down to) is 0.6v

The problem is they are a little sensitive to environmental effects. When charging they get warm and you have to allow the temperature to stabilize to ambient at 20°c. Then they should have no discharge current at all otherwise that will skew the reading down, it doesn't take much to take it down to below 12v so the only accurate way is to disconnect the battery and leave it for an hour or two stabilise

Also what the voltage won't tell is its capacity. A fully charged battery will read 12.6v even if it has half the capacity.
 
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HoriUK said:
Anyway, as our car is now a whopping 14 months old it looks like we'll have to cough up for a replacement - anyone know how much the dealers charge for one, or what regular battery size fits? Cheers.
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If you do decide to replace your battery, I know a lot of the trade use the service of these people.
It's an on-line service with next day delivery and if you enter your registration number in the field supplied in the link, it should offer you what is available for your model.
If not, give them a call and they will tell you what WILL fit and options on different capacities.

www.tayna.co.uk

Car Batteries - Motorcycle Batteries - Leisure Batteries - Cheap Prices!

Tayna Batteries offer batteries for all applications at cheap prices. We specialise in Car Batteries, Leisure Batteries, Motorcycle Batteries and Mobility Batteries. With the UK's widest range of famous brands and next day delivery we cannot be beaten.
www.tayna.co.uk www.tayna.co.uk
 
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HoriUK said:
Evening all. Looks like this cold weather has done for our 12v battery - after a week of the infotainment playing up, today the car was totally dead.

Our neighbour kindly (especially as the AA aren't responding to homestarts today) gave us a jump, and when it came back to life I think it went though every warning it's got! Annoying, as when I looked yesterday it was reading 14.5v (now 13.7v).

Anyway, as our car is now a whopping 14 months old it looks like we'll have to cough up for a replacement - anyone know how much the dealers charge for one, or what regular battery size fits? Cheers.

View attachment 13783
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Hi Horiuk, My MG4 shut down a bit like your 5 and the AA powered it up again . I took it to main Dealer they could fine any real reason for this but once recharged all seems fine.
i would re-charge and test , get dealer to check fault log, well worth the hassle.
 
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