12V Battery Size

[Pebblefeline]

Hi guys happy new year (nearly)

I want to replace my 12V with a varta 075, it’s a little bigger than the oem battery.

Has anyone had any problems putting in a slightly larger dimension battery or does the fixing adjust?

Many thanks

Jae

Looking at some other posts, sorry I missed them, an 075 will fit even though the original is a T5.

Is there anything else I need to think about? I am planning a non start stop calcium wet battery in 075 size slightly higher start power and capacity thank the saic oem.

Any advice appreciated

Thanks all

 

[CanyonReveller]

MG5s seem a bit fussy over the 12v supply, so personally I'd go for a premium silver battery from Yuasa. A marginal increase in cost for a battery that'll probably outlast the car!

 

[MickeySw]

Is there anything else I need to think about?

Regardless of what you replace it with, make sure the SC052 update (increase aux battery voltage) was done on your car to get optimum life out of a new 12V battery

 

[Pebblefeline]

Yeah the dealer could only find this for the zs Ev not for the mg5

Going to a new dealer this year
Does the size etc sound right for the new battery?

 

[Gomev]

You don't really need higher power, there is no engine to crank over.

 

[Pebblefeline]

All good
Normal Charging voltage is up to 14.3 from 13.8


Old battery seems to be ok and is now powering the Mazda bongo which had a totally dead battery

Happy times

Thanks for all your replies happy new year

 

[1UKDUDE]

I need a new 12v battery on my pre facelift mg5 - is the correct battery a 027 ?

 

[CanyonReveller]

027 and 075 are the same except for the height. The height of the 027 is 190mm the height of the 075 is 175mm. What's the height of your current battery?

 

[Pebblefeline]

The 075 is spot on for me
Same size as the oem

 

[1UKDUDE]

My MG 5 was taken in 3 weeks before Xmas as the dash was like a xmas tree with multiple errors I was going on holiday over xmas so I left it with them - was told all the modiles required software updates - this was done and test drove and all fine - I went to collect the car yesterday and the 12v battery was flat on collection! never had a problem with it before - they did not have one in stock and its not under warrenty! - So I said jump start the car and i will take it home and put it on charge - but the battery is not holding charge - the barrery fitted is a 027N NAPA - I can get the same battery from Tanya £86.52 and it comes with a 5 year gaurantee ! so i dont know why the mg warrenty dont cover the one fitted for 5 years

 

[Jaumg]

My MG 5 was taken in 3 weeks before Xmas as the dash was like a xmas tree with multiple errors I was going on holiday over xmas so I left it with them - was told all the modiles required software updates - this was done and test drove and all fine - I went to collect the car yesterday and the 12v battery was flat on collection! never had a problem with it before - they did not have one in stock and its not under warrenty! - So I said jump start the car and i will take it home and put it on charge - but the battery is not holding charge - the barrery fitted is a 027N NAPA - I can get the same battery from Tanya £86.52 and it comes with a 5 year gaurantee ! so i dont know why the mg warrenty dont cover the one fitted for 5 years

That is woeful service, what a terrible start to the new year!

 

[MickeySw]

! so i dont know why the mg warrenty dont cover the one fitted for 5 years

Simple, the OEM 12V aux is unlikely to last 5 years…

 

[1UKDUDE]

I have bought the same battery identicle part number to the origonal 027N NAPA form Tanya this comes with a 5 year gaurantee. -( From Here )

The Car was left with MG Chesire oaks for over 3 weeks as eml and all the abs etc shut down, they said on arrival the 12v battery was dead ! it was and has been fine, I know the AA disconected the 12v battery when they towed it in, they said they charged it and uspadeted all the software test drove it and all is fine ! - when i went to collect it the 12v was dead they did not have a battery in stock, Hence i told them to Jump it and i would charge the battery - I got it home and tried to charge it but it was not holding a charge - hence new battery now fitted .
I just hope those dash lights dont come back on - its been running for over 2 years without a problem and on the old software - I cant see a software update fixing the problem and i think its only a matter of time before it happens again !

 

[Gomev]

I have bought the same battery identicle part number to the origonal 027N NAPA form Tanya this comes with a 5 year gaurantee. -( From Here )

The Car was left with MG Chesire oaks for over 3 weeks as eml and all the abs etc shut down, they said on arrival the 12v battery was dead ! it was and has been fine, I know the AA disconected the 12v battery when they towed it in, they said they charged it and uspadeted all the software test drove it and all is fine ! - when i went to collect it the 12v was dead they did not have a battery in stock, Hence i told them to Jump it and i would charge the battery - I got it home and tried to charge it but it was not holding a charge - hence new battery now fitted .
I just hope those dash lights dont come back on - its been running for over 2 years without a problem and on the old software - I cant see a software update fixing the problem and i think its only a matter of time before it happens again !

Pedant alert, ..... Tayna, not Tanya although I'm sure she is a perfectly nice person.

 

[1UKDUDE]

Update all the dash lighs came on again so the car will be going back to MG Chesire oaks - as i said i cant see a software update fixing the problem - the car is 28 months old and has never had this problem before - I think its an abs sensor and the light come on when slow and braking

 

[WigglePig]

Ever since I got my 5 in 2021 I have been perplexed by the indicated 12V battery voltage when the vehicle is running...I would expect to see 14.2 V as a minimum for charging it but it always displays 13.8 V, confirmed at the battery with a DMM.

Am I missing something here? I mean I know the traditional startup draw isn't there but I would still expect to see more than 13.8 V...

 

[DBedford]

Our ZS is showing 13.1V. as you say the higher terminal voltage is required to cover the voltage drop when the starter motor is used. On a EV the biggest current draw may be the heater or the wipers. so a higher off-load terminal voltage is generally not required.

Now shows 14.7v after sitting in it for a few minutes playing with Car Scanner !

 

[Jaumg]

Ever since I got my 5 in 2021 I have been perplexed by the indicated 12V battery voltage when the vehicle is running...I would expect to see 14.2 V as a minimum for charging it but it always displays 13.8 V, confirmed at the battery with a DMM.

Am I missing something here? I mean I know the traditional startup draw isn't there but I would still expect to see more than 13.8 V...

Mine shows 13.8V when the headlights are on and 14.1V when they're off. I think i heard that there's an update that brings both voltages higher.

 

[Alb]

It just indicates that the charging supply is current limited.
Both voltages are fine and show that the battery is charging.

 

[Coulomb]

.I would expect to see 14.2 V as a minimum for charging it but it always displays 13.8 V, confirmed at the battery with a DMM.

14.2 isn't good for a lead acid battery for too long. 13.8V is a recognised float voltage, i.e. one that will maintain the battery at full charge, but is safe to leave at that voltage long term (even years, in the case of an uninterruptable power supply).

Those voltages are for 25°C, it needs to be a little higher (e.g. 0.5V higher at -3°C) in colder temperatures.