12V Battery Replacement

MadBaz

MadBaz

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Location
Longtown Uk
Driving
MG3 Hybrid+ Trophy
Hi has anyone replaced the 12volt battery in the boot on their MG3 Hybrid ? Mine has decided to lose charge , dropped from 12.6 to 11.4 in four days garaged. It charges back up after a drive so it’s not an alternator problem but the battery not retaining its charge.
Wondering if it would at to get a new battery but struggling to find one that fits this car .
 
Will be contacting them tomorrow about it , just trying to see if it’s a common problem with other owners or just my car. Gathering as much info as possible in case they try to fob me off , as for warranty will find that out as well.
 
No problems here, have had mine since June - regularly indicates 14.5v. Makes you wonder how accurate the reading is on the dash? Well protected in the boot but shame about any spare wheel.
 
Have been logging off the app for the last few days and was hoping it would improve but just looked again and it’s down to 11.5 🤷‍♂️
IMG_3508.jpeg
 
Yes it’s from the app , l get a low battery warning on the dash when opening the doors and also one when stopping the engine. Phoning the garage in the morning to arrange a check up.
 
Good morning all, I had similar concerns after noticing via the app that the battery appeared to be losing charge whilst sitting in the garage, I had the low battery warning come on once. My vehicle was checked at my excellent local MG dealership (Hawkins Blackwater) and given a clean bill of health.

Anyway the purpose of this post is to report that I returned from a 2 week holiday on Saturday where my vehicle was parked outside in a hotel car park.

When I returned it was -4 degrees with my vehicle covered in frost, not only did my vehicle go into "ready" mode with no problems, it actually remained in EV mode until I turned on the heated seats and steering wheel. Prior to leaving my vehicle I had a journey of approximately 80 miles.

I hope this gives some peace of mind regarding the 12v battery.

Bye for now.
 
14.5V is the charging voltage and that's OK. After switching off the car the voltage drops quite quickly, which is completely normal. It's not too bad for a battery to drop to 11.5V in cold temperatures, but it shouldn't go much lower.
 
Thanks for that , it’s going to the dealership tomorrow to be checked over , the lowest l have seen is 11.4 . Will update the thread when l return .
 
I don't know how it is with MG. With Dacia Hybrids, the 12V battery is only needed for basic devices such as ventilation, window lifters, unlocking the car and activating the drive battery. When the 12V battery runs down, it is recharged by the drive battery or generator.
Dacia hybrids do not have a starter motor to start the combustion engine or an alternator.
Unfortunately I haven't been able to look under my ZS Hybrid+ to see if it has a starter and alternator.
 
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