12V battery size

gazza487

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Just got round to fitting a new battery in preparedness for winter as the battery voltage has been getting a bit on the low side and it’s 2 years old. Erm the 027 I have doesn’t fit properly unless I’m going mad the front bracket doesn’t fit as the battery is longer ???
 
I am really surprised that you believe your needed a new battery already. 2 years old doesn't seem much nowadays.
 
I am really surprised that you believe your needed a new battery already. 2 years old doesn't seem much nowadays.
It’s a bit of a story - including it being left open for a considerable amount of time. Boot open and someone putting the car on charge when it didn’t need it for quite some days despite it being 80% when left with them. Me thinks the 12V went flat and they tried to recover it !! The app was showing the battery at 12V which I’ve never seen either so for safeties sake.

Anyhoo Halfords list an 012 battery which is a smaller beast for my reg. Tayna say 027 which I can’t get the bracket to fit.
 
Last edited by a moderator:
012 is indeed the correct size - just saying! Also, I’ve noticed on the display with tyre pressures it is holding the battery at 14.2V rather than 13.9V. Something is clearly different but my electrochemistry days have been forgotten to know exact meaning ?
 
Last edited by a moderator:
012 is indeed the correct size - just saying! Also, I’ve noticed on the display with tyre pressures it is holding the battery at 14.2v rather than 13.9v. Something is clearly different but my electrochemistry days have been forgotten to know exact meaning ?
14.2V and 13.9V are not used to determine whether the battery has reached the end of its life, because it will calculate the remaining power and ambient temperature and adopt different charging strategies.
 
Last edited by a moderator:
14.2V and 13.9V are not used to determine whether the battery has reached the end of its life, because it will calculate the remaining power and ambient temperature and adopt different charging strategies.
Hi Kenneth. Do you have some MG insider information? do you service or work for them in some way maybe?
 
I've taken the decision to replace the 12V battery before it lets me down. The car is just over 2 years old from the date of manufacture and as the supplied battery only has a 12 month warranty I thought I'd replace it and get the most use out of the new battery.

I've gone for a Yuasa from Amazon and thought £62.90 for peace of mind was worth it. I'll let you know how I get on when it arrives and it's fitted.

 
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012 is indeed the correct size - just saying! Also, I’ve noticed on the display with tyre pressures it is holding the battery at 14.2V rather than 13.9V. Something is clearly different but my electrochemistry days have been forgotten to know exact meaning ?
The voltage shown on the TPMS screen is the charging voltage, the higher it is the more charge the car is trying to put in. This may increase if the headlamps are on or if the battery is low.
 
I've taken the decision to replace the 12V battery before it lets me down. The car is just over 2 years old from the date of manufacture and as the supplied battery only has a 12 month warranty I thought I'd replace it and get the most use out of the new battery.

I've gone for a Yuasa from Amazon and thought £62.90 for peace of mind was worth it. I'll let you know how I get on when it arrives and it's fitted.

Same one I replaced mine with a few weeks ago - maybe 45 minutes to fit, needs the bracket holding it down undoing as well as the fabric strap over the battery. Also undid 2 of the screws holding down the large black plastic cover as that needed moving slightly to get the battery out.

Luke you - £70ish for 5 year warranty and peace of mind seems well worth it.
 
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I've taken the decision to replace the 12V battery before it lets me down. The car is just over 2 years old from the date of manufacture and as the supplied battery only has a 12 month warranty I thought I'd replace it and get the most use out of the new battery.

I've gone for a Yuasa from Amazon and thought £62.90 for peace of mind was worth it. I'll let you know how I get on when it arrives and it's fitted.

UPDATE: Battery has arrived and fitting took 20 minutes including removing the large plastic cover and applying Liqui-Moly battery clamp grease. Apart from the usual warnings and having to turn the steering wheel lock to lock a couple of times it as an easy job.

If needed replacement clips for the large plastic cover are the same as Mini wheel arch clips. Don't ask how I know 🤣
 
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It's been a fortnight since I fitted the new battery and I've noticed that when I check the 12V battery voltage on the app after its been standing overnight it's never higher than 12.5V whereas with the original it was often 14.6V plus and would drop as low as 11.8V.

I guess that shows the original battery was, using the technical term, knackered.
 

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