Anyone had the red battery warning indicator show?

highsider

Standard Member
Joined
Jun 12, 2023
Messages
27
Reaction score
23
Points
14
Location
Cheltenham
Driving
MG4 Trophy LR
I was trying to charge the car at a public charger last week, and it wouldn't connect to start charging. I noticed the driver display was showing a red battery indicator. Looking at the manual, it said it was a Low-voltage Battery Charging System Malfunction Warning Lamp.

Screenshot from 2023-09-27 22-32-37.png


I locked the car and left it for a while. Returning to the car later, the indicator doesn't show and the car started to charge fine.

I was going to contact the dealer, but it seems to rectify itself.

Anyone else experience this?
 
Hi, I just saw the same warning light on my car today. I was driving during the weekend and left the car in the garage, connected to the charger with a schedule to slowly charge from my solar system at home (13:00 to 16:30).

It charged just fine yesterday, but today, when I got in to setup the charge current at 6A (cloudy day), I got the error message. As soon as the car restarted the charge (it always stops charging when you open the door), the error icon went off and the battery voltage showed 14.1V, so it is clearly charging. I'll check actual voltage with a multimeter tonight, after the current schedule finishes, and report back.

I'm inclined to think this is just another of those glitches, like the low temperature warning I get from time to time, even though ambient temperature has been over 25 °C from the moment I bought the car back in July.

Update: I didn't check actual voltage with the multimeter, but I've verified that, after the charge schedule finished, the low voltage battery was sitting at 12.7V (fully charged) and went up to 14V a bit after I powered the car on. The battery warning light didn't came up this time.
 
Last edited:
I had the same problem today, not able to charge and the red battery sign was on, however the voltage was 14.1V.
Tried later again and all was oké again.
Trophy R46 phase1
 
I had this on Sunday. I reported in the thread '12v battery charging'. It may be linked to the colder weather. Since Sunday I have not had a problem but I am monitoring the voltage.
 
As the 12v is susceptible to discharging (and not being topped up by the HV battery) if:
1. A charger is connected but not charging the car
2. The HV battery is lower than 20% charge
3. Weather temperature changes
4. The above coupled with App interrogations of the car

I have installed the below and find its very useful. It will notify you of a low battery condition and you can set how low etc. However, be careful installing as the MG4 has a support bar running across the middle of the battery, so waving spanners around in that area is just asking for a new hair style !

BM2 Battery Monitor
 
My current thought is, get a battery booster pack and carry it. If it starts you that quickly, then you're scarcely delayed. If it happens repeatedly, then replace the battery or investigate why it isn't charging up.
 
I'm starting to consider replacing the lead acid battery by one of those compatible 12V lithium batteries. They have the same form factor and integrate a charger inside, so it should be plug and play solution.
 
There has been some discussion about that on one of the other 12v battery threads. Probably this one.

 
I had the same problem today, not able to charge and the red battery sign was on, however the voltage was 14.1V.
Tried later again and all was oké again.
Trophy R46 phase1
If the 12v battery was at 14.1v it means it was being charged from the HV battery. You would get a similar reading from an ICE car with the engine running, and the alternator charging the battery.

It would suggest that you cannot charge the HV battery if the 12V battery is low.
 

Are you enjoying your MG4?

  • Yes

    Votes: 510 79.3%
  • I'm in the middle

    Votes: 86 13.4%
  • No

    Votes: 47 7.3%
Support us by becoming a Premium Member

Latest MG EVs video

MG3 Hybrid+ & Cyberster Configurator News + hot topics from the MG EVs forums
Subscribe to our YouTube channel
Back
Top Bottom