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MG ZS EV HV Battery shut off

Andrew

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When I push the start button twice so the green light is showing on start button, I now get the following warning
HV Battery Shut off
My foot is not pressed on the brake pedal, did notice the 12 volt battery was showing 12 volt usually 1 bar above, I'm sure this has never appeared before, drive 30 miles to work, switched off then 2 presses of the start button, again the same message.

Is this the norm?

HV Battery shut off.jpg
 
Try charging the HV battery as this also charges the normal 12v battery at the same time.
I have myself had this HV shut off before, but this is normally if you push the start button with the brake pedal depressed, but then releasing the brake pedal too soon.
I’ve never had this otherwise, but my 12v battery has never been that low as I drive frequently for work and therefore mainly charge the car daily.

My 12 normally sits 1 or 2 bars over the centre 12v marker.
 
After noticing the message and the voltage of the 12 volt battery, I placed the 12 volt battery on charge over night and in the morning pressed the start button twice so green light on and still got the HV battery shut off message and the voltage on the screen was again showing 12 volts,. The main battery was at 90% charge. Hold my foot on the brake pedal, push start button again, the car powers up and the 12 volt battery charge indicator goes up 2 bars.
Got the car booked into the dealers in July, so well ask then to check.
 
After noticing the message and the voltage of the 12 volt battery, I placed the 12 volt battery on charge over night and in the morning pressed the start button twice so green light on and still got the HV battery shut off message and the voltage on the screen was again showing 12 volts,. The main battery was at 90% charge. Hold my foot on the brake pedal, push start button again, the car powers up and the 12 volt battery charge indicator goes up 2 bars.
Got the car booked into the dealers in July, so well ask then to check.
Looking forward to what’s said...
 
Andrew,

Just as a matter of interest why do you want to press the start button twice with your foot off the brake pedal?

Frank
 
guys, for future.. please refer to this video related to the battery charging .. it seems spending few more pound to keep a charger isnt bad.
 
The reason I press start button twice with my foot off the brake pedal is because i'm having trouble with the my phone connecting with Android auto and the entertainment screen freezing completely, only after leaving the power switched off for 20 minutes will the screen turn back on, many electrical problems with the car, so as i'm playing around with the car I normal double press the start button, but lately i'm now seeing the hv battery shut off screen which I didn't think I've seen before. The latest happening was the message which appeared twice the other day that the front camera was blocked which i lucky took a picture of. I am thinking that may be the comfort update will sort the problems, but will the dealer do this under warranty?
Front camera blocked.jpeg
 
I have also had this front camera blocked but only when the car was covered in ice or when the windscreen was misted; generally once cleared the camera is fine.
 
Please don't waste the dealers time with this one, it's perfectly normal! When you double click the start button without your foot on the brake the car powers up the auxiliary 12v system only as it's meant to. The car is just confirming that it's not in ready to drive mode and the HV battery is offline. It's also normal for the 12v battery to show 12v in this state. If you intend to run the 12v system for more than a few minutes, I'd advise you power up the car with foot on the brake, this will ensure the 12v battery is charging.
 
Well worth knowing in these unusual times, where one person may want to stop in the car, perhaps while the other is shopping.

I have seen something similar before and now always keep my old ICE emergency jump starter in the car.

I don't know if you have ever used one? It's about the size of a small box of chocolates, fits in a neat leatherette case and had two very short heavy duty leads that plug in. You wouldn't think it could start anything....but amazingly it can...only about £30ish...good to have one in any car...just in case. They will also re-charge dead iPhone batteries in an emergency. ;)
 
Thanks for letting me know Paulie68, will not waste dealers time with this one, nice if this information was in the users manual.
 
I agree with @Pualie68 the message you are getting is appropriate and correct.
The HVB will automatically shut of for any any start button sequence that does not proceed to the Ready state. The HVB comes on only in the ready state.
There is absolutely nothing wrong with your car. The message actually indictates that the energy protection circuit in the car is working appropriately. That is the HVB is going off when you do not need it.
As already advised regular slow charging ensures your 12VB (LVB) as well as the HBV are in a good state of charge.
 
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Thanks for letting me know Paulie68, will not waste dealers time with this one, nice if this information was in the users manual.

Manual... I was reading it yesterday and spotted a comment about being careful not to burn yourself on the hot exhaust when jacking the car up!! lol!!
 
Yes this is a well know error in the ZS EV manual. It is thought to be the result of a "cut and paste" from the ZS ICE manual. MG it seems we're too lazy to do a re-write.
 
Well worth knowing in these unusual times, where one person may want to stop in the car, perhaps while the other is shopping.

I have seen something similar before and now always keep my old ICE emergency jump starter in the car.

I don't know if you have ever used one? It's about the size of a small box of chocolates, fits in a neat leatherette case and had two very short heavy duty leads that plug in. You wouldn't think it could start anything....but amazingly it can...only about £30ish...good to have one in any car...just in case. They will also re-charge dead iPhone batteries in an emergency. ;)

I don't think you're supposed to jumpstart the 12v battery of any EV. I think it might be downright dangerous but at least it can turn your computer braindead or the power converter of the computer, since both won't digest high voltage very well.
 
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@ARvanHAS,
I agree with your comment on NOT jump starting EVs.
All the information I have to date indicate no need to charge the 12VB if one charges the HVB regularly.
I have not come across information stating directly that do not jump start the 12VB on an EV. Hence I put the question to my EV Boffins. They laughed their heads off and just said the situation where the 12VB was dead but the HVB had adequate charge is not meant ever to happen in normal everyday EV usage. The only time it may occur is storage for more than 2-3 month. Solution for that situation for ZS EV is to remove the connection leads to the negative pole of the 12VB during the storage period then reconnect and charge the car as normal after storage period before using the car. In the opinion of my boffins, when the situation occurs in normal use that the HVB is OK but 12VB is dead then there is something seriously wrong with the circuits in the car and the solution is not jump starting.
 
@Kithmo,
Yes I have seen this. In the opinion of most EV boffins this is a nonsense and a result of MG's lazy cut and paste approach from the ICE manual.
It says....
Screenshot_20200709_165634_com.adobe.reader.jpg
Just imagine your 12BV and your HBV are both flat.
No amount of Emergency starting with jump leads will get you anywhere in such a situation.
What should have happened here is that they should have differentiated between HBV being flat and 12BV being flat while has HBV has adequate charge.
Now since most EV observers think that flat 12BV with adequate charge HBV situation should not occur in normal use they also tend to disagree that the approach to resolving it when it occurs is simply to jump start.
The general EV advice is that in normal use (ie regular drive and top up charge) flat 12VB with adequate HBV charge should not occur. If it occurs get your vehicle checked.
If is occurs anyway then charging the EV to ensure the 12VB also recharges is one recommended option.
The jump start option is not advised by most. That is all one can say for sure on this issue.
 
I don't think you're supposed to jumpstart the 12v battery of any EV. I think it might be downright dangerous but at least it can turn your computer braindead or the power converter of the computer, since both won't digest high voltage very well.
Its fine to put a 12volt power pack on the 12v battery or jumper cables from another vehicle thats not running if your 12v battery is flat.
 
I asked my chum also a Chris, who is an AA man of many years standing. He says they come across a lot of EV's especially at the Docks. They frequently use a 'power pack on the 12 volt but they dont use Jump leads....
sort that one out..?.....( our posts crossed!!)
 
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