12V Battery Size

P

Pebblefeline

Established Member
Joined
May 21, 2024
Messages
195
Reaction score
128
Points
62
Location
lincoln
Driving
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
 
Last edited by a moderator:
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!
 
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?
 
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
 
Last edited by a moderator:
I need a new 12v battery on my pre facelift mg5 - is the correct battery a 027 ?
 
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?
 
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
 
1UKDUDE said:
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
Click to expand...
That is woeful service, what a terrible start to the new year!
 
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 !
 
1UKDUDE said:
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 !
Click to expand...
Pedant alert, ..... Tayna, not Tanya although I'm sure she is a perfectly nice person. :)
 
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
 

Attachments

  • IMG_4235.jpg
    IMG_4235.jpg
    54.5 KB · Views: 36
  • IMG_4237.jpg
    IMG_4237.jpg
    62.8 KB · Views: 36
Last edited:
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...
 
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 !
 
Last edited:
WigglePig said:
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...
Click to expand...
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.
 
It just indicates that the charging supply is current limited.
Both voltages are fine and show that the battery is charging.
 
WigglePig said:
.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.
Click to expand...
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.
 

Similar threads

biffo
Replacing 12V Battery
2
Replies
30
Views
2K
biffo
biffo
M
12V battery not charging
Replies
18
Views
2K
Mr Gear
M
C
Brand new 12V battery discharging
2 3
Replies
54
Views
2K
pollenface
pollenface
R
MG 5 LR 12v battery replacement
Replies
3
Views
1K
m4rmite
M
Stuart Wright
12v battery problems, causes and solutions
Replies
1
Views
777
John11000
J
Support us by becoming a Premium Member

Latest MG EVs video

MG Hybrid+ EVs OVER-REVVING & more owner feedback
Published
Subscribe to our YouTube channel
Back
Top Bottom