12v battery

sandra54

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Location
Scotland
Driving
MG ZS EV
Owner of MGZS Ev Long range. A month or so after taking delivery the car wouldn’t start. AA called, charged battery got me to dealer. This is visit 1 , charged battery , caused by not being fully charged on delivery . I already had the car booked in as it was showing a “ do not park for more than 3 days “ message. All good.
Still same error coming up .. visit 2 . Battery health good, showing no drainage of battery. A day or so same message plus airbag warning. Visit 3 new sensor fitted, battery heath good , no drainage BUT did I always lock the car with key/ button whenever I switched the car off? Well not a 100% probably. Bingo this is the problem 😳 . 1day later.. battery warning , don’t park, some functions may not be available, air bag warning. Phoned garage really just to have it on record. Bring it in next week. In the meantime , more serious warnings of 12v battery fault, flashing hazard sign Audible ping… pull over when safe !!!
Visit 4 … 2 days… all good , battery a little drained but now charged!!
How can not locking your car 100% cause all of this ?? I’ve absolutely no confidence that the car is now “ warning free “ Cant wait till I go on holiday for 2 weeks, dear knows what the state of play will be then!
I apologise for very long post but I’m beyond frustrated with it all . Anyone gone through similar?
 
Owner of MGZS Ev Long range. A month or so after taking delivery the car wouldn’t start. AA called, charged battery got me to dealer. This is visit 1 , charged battery , caused by not being fully charged on delivery . I already had the car booked in as it was showing a “ do not park for more than 3 days “ message. All good.
Still same error coming up .. visit 2 . Battery health good, showing no drainage of battery. A day or so same message plus airbag warning. Visit 3 new sensor fitted, battery heath good , no drainage BUT did I always lock the car with key/ button whenever I switched the car off? Well not a 100% probably. Bingo this is the problem 😳 . 1day later.. battery warning , don’t park, some functions may not be available, air bag warning. Phoned garage really just to have it on record. Bring it in next week. In the meantime , more serious warnings of 12v battery fault, flashing hazard sign Audible ping… pull over when safe !!!
Visit 4 … 2 days… all good , battery a little drained but now charged!!
How can not locking your car 100% cause all of this ?? I’ve absolutely no confidence that the car is now “ warning free “ Cant wait till I go on holiday for 2 weeks, dear knows what the state of play will be then!
I apologise for very long post but I’m beyond frustrated with it all . Anyone gone through similar?
No Sandra - I have not gone through any of this ordeal with either of my two ZS EV's ?.
I am puzzled why after this many visits, why they have not replaced the 12 volt battery.
Of course they require permission to do so, from the MG mothership at customer services.
This barrage of erroneous messages popping up, can indicate a fault battery.
It maybe charging okay when the car is in ready mode or on charge, but it could be draining when the car is closed down.
Have they check the car for a parasitic drain ??.
Which basically means that something is still pulling power from the 12 volt battery when the car is closed down.
Suggesting it happens because you have failed to lock the car is odd.
First of all, why would you not do this anyway ????.
And why would this drain the battery, unless the car was still in ready mode or you had left the door(s) ajar.
If you are due to go on holiday and you are rightfully concerned, can I suggest you purchase a 12 volt boaster pack and take it with you.
Of course you have MG Recovery ( A.A. ) but you may have a long wait at busy time periods.
 
How is the car being used?
If it's just occasional short journeys and infrequent charging the 12V battery may not be getting enough time "on charge" to keep it topped up & healthy.
If the car gets regular longer journeys and is left on charge every night and the 12V battery is still going flat it points to it being faulty.
Regarding locking the car: the radio stays on for 10 minutes or until the car is locked so there are probably other systems that don't shut down fully as well. These will all be draining the 12V battery, even if only for 10 minutes, so yes, lock the car when you get out.
 
I would get them to swap the 12v battery if only to eliminate it from being faulty.
To me that’s the most obvious solution! However I suppose as the battery is “ in good health “ they haven’t done so. I e accepted locking the car 100% is the way forward but why the dire warnings to pull in safely etc.
 
why the dire warnings to pull in safely etc.
12v system powers the control systems and critical things (airbag is powered off it as are critical sensors) so you can understand it.

One of the signs of a bad 12v battery in a lot of cars is it throwing random errors on various sensors as low power through them sends incorrect readings.
 
The 12 volt battery has its own manufacturers warranty and should be changed. I imagine they are not doing a load test to see if it holds its charge under stress.

I would ask the dealer what the warranty is for the 12 volt battery (usually 2 years) and why they haven't changed it.
 
12v system powers the control systems and critical things (airbag is powered off it as are critical sensors) so you can understand it.

One of the signs of a bad 12v battery in a lot of cars is it throwing random errors on various sensors as low power through them sends incorrect readings.
Thanks, yes I can understand that, but if the battery is showing “ good health “ at the garage does that indicate the battery should just be replaced.?
 
I would ask the dealer what the warranty is for the 12 volt battery (usually 2 years) and why they haven't changed it
Think MG only give 1 year warranty on battery with a claim limit of £100 your property better off buying a premium replacement with its own five-year warranty
 
Think MG only give 1 year warranty on battery with a claim limit of £100 your property better off buying a premium replacement with its own five-year warranty
It’s expense for you to carry, but if you are going on holiday this is a good suggestion by @N2STY.
You don’t want to be spending your holiday on the back of a low loader and stuck at a dealership miles away.
If it fixes the problem, you can speak to your dealer on your return, regarding reimbursement of your outlay.
Keep the receipt of course !.
 
Thanks, yes I can understand that, but if the battery is showing “ good health “ at the garage does that indicate the battery should just be replaced.?
It indicates the garage doesn't want to replace it under warranty.
If everything has been OK since visit 4 they might be right, but if you get any more error messages at all it clearly can't hold a charge and needs replacing. Whether you dig your heels in for a warranty claim or spend £100+ and do it yourself is up to you.
 
Owner of MGZS Ev Long range. A month or so after taking delivery the car wouldn’t start. AA called, charged battery got me to dealer. This is visit 1 , charged battery , caused by not being fully charged on delivery . I already had the car booked in as it was showing a “ do not park for more than 3 days “ message. All good.
Still same error coming up .. visit 2 . Battery health good, showing no drainage of battery. A day or so same message plus airbag warning. Visit 3 new sensor fitted, battery heath good , no drainage BUT did I always lock the car with key/ button whenever I switched the car off? Well not a 100% probably. Bingo this is the problem 😳 . 1day later.. battery warning , don’t park, some functions may not be available, air bag warning. Phoned garage really just to have it on record. Bring it in next week. In the meantime , more serious warnings of 12v battery fault, flashing hazard sign Audible ping… pull over when safe !!!
Visit 4 … 2 days… all good , battery a little drained but now charged!!
How can not locking your car 100% cause all of this ?? I’ve absolutely no confidence that the car is now “ warning free “ Cant wait till I go on holiday for 2 weeks, dear knows what the state of play will be then!
I apologise for very long post but I’m beyond frustrated with it all . Anyone gone through s
 
What voltage is your battery showing in the car it should be between 12 and 14 volts anything lower and it's faulty. First thing to try is a replacement battery.
 
Owner of MGZS Ev Long range. A month or so after taking delivery the car wouldn’t start. AA called, charged battery got me to dealer. This is visit 1 , charged battery , caused by not being fully charged on delivery . I already had the car booked in as it was showing a “ do not park for more than 3 days “ message. All good.
Still same error coming up .. visit 2 . Battery health good, showing no drainage of battery. A day or so same message plus airbag warning. Visit 3 new sensor fitted, battery heath good , no drainage BUT did I always lock the car with key/ button whenever I switched the car off? Well not a 100% probably. Bingo this is the problem 😳 . 1day later.. battery warning , don’t park, some functions may not be available, air bag warning. Phoned garage really just to have it on record. Bring it in next week. In the meantime , more serious warnings of 12v battery fault, flashing hazard sign Audible ping… pull over when safe !!!
Visit 4 … 2 days… all good , battery a little drained but now charged!!
How can not locking your car 100% cause all of this ?? I’ve absolutely no confidence that the car is now “ warning free “ Cant wait till I go on holiday for 2 weeks, dear knows what the state of play will be then!
I apologise for very long post but I’m beyond frustrated with it all . Anyone gone through similar?
Update
The garage have now replaced the 12 v battery. It was fully charged last night and down to 10v this morning at the garage. ! I’m told that everything is good, I hope so but ..,,
 
Update
The garage have now replaced the 12 v battery. It was fully charged last night and down to 10v this morning at the garage. ! I’m told that everything is good, I hope so but ..,,
Had they have done this check on first visit, we would not be having this conversation now !.
When a so called, brand new battery repeatedly looses it charge, there has to be a good reason for it to do so.
Faulty battery or parasitic drain by the car itself.
Just charging it back up and returning it to the customer is a complete waste of every bodies time.
The car was indicating a problem and the random warning lights where the first clue here.
A drop check on the 12 volt battery would have identified the problem.
Charging the battery to full and then leaving it disconnected from the car over night, was enough proof when the SOC dropped to 10 volts, the battery was incapable of retaining a full charge.
I am glad you are now sorted.
It is easy to see and understandable, that you have some concern about this situation.
A really easy way to keep a check on the status of your 12 volt battery, is to install a battery monitor.
It is really easy to install and then you are able to check on the SOH of your 12 volt battery from a App on your phone.
It will even notify you if it thinks the battery voltage is getting low.
This little simple device is a easy fit and will help restore your confidence.
Here is a great video that explains how it works on an EV and how it is installed.
There is a link provided to purchase one for around £21.

 
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