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Not all batteries degrade quickly if not kept fully charged, different chemistries like different states. Li based batteries for example, have the greatest longevity when charged to around 80%.

Hence well designed electronic manufacturers fool you, when they say the battery is 100% charged, in reality it’s only charged up to 80%.

Apple have introduced “Optimised charging” to only charge to “100%” for the shortest amount of time before use (based on your previous usage patterns), and I believe the A250e also runs a similar charge program when allowed to.
 

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Not all batteries degrade quickly if not kept fully charged, different chemistries like different states. Li based batteries for example, have the greatest longevity when charged to around 80%.

Hence well designed electronic manufacturers fool you, when they say the battery is 100% charged, in reality it’s only charged up to 80%.

Apple have introduced “Optimised charging” to only charge to “100%” for the shortest amount of time before use (based on your previous usage patterns), and I believe the A250e also runs a similar charge program when allowed to.
True but I think we are taking about AGM batteries sent we?
 

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Don't think I can wait till the first service in Feb to sort out my A35 battery. I have a total of 26 battery warnings since the start of November I've charged the battery on a number of occasions and I now carry a jump starter in the back of the car. First time I've had to do that since my Austin A35 in the 60's. Must be something to do with the designation 'A35' Looks like we haven't made much progress since then, the car wouldn't start this morning as I hadn't used it yesterday. Unbelievable.
 

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First time I've had to do that since my Austin A35 in the 60's. Must be something to do with the designation 'A35' Looks like we haven't made much progress since then, the car wouldn't start this morning as I hadn't used it yesterday. Unbelievable.
Ah those were the days 🤣 Every winter morning was a voyage of discovery, would it start, wouldn't it? 🤣🤣🤣
 

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Don't think I can wait till the first service in Feb to sort out my A35 battery. I have a total of 26 battery warnings since the start of November I've charged the battery on a number of occasions and I now carry a jump starter in the back of the car. First time I've had to do that since my Austin A35 in the 60's. Must be something to do with the designation 'A35' Looks like we haven't made much progress since then, the car wouldn't start this morning as I hadn't used it yesterday. Unbelievable.
Take it in, tell them to look at TIPS GI54.10-P-071664
 

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And don't forget having to thump the bulkhead to keep the SU fuel pump ticking.
🤣🤣🤣 I had forgotten all about that one.

Did you carry a lump of wood to hit the starter motor when it got jammed, I carried one for years 🤣

The things we had to endure just to keep our cars on the road 😁
 

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🤣🤣🤣 I had forgotten all about that one.

Did you carry a lump of wood to hit the starter motor when it got jammed, I carried one for years 🤣

The things we had to endure just to keep our cars on the road 😁
And they've come back to haunt me after 39 cars, many of which are on my 'wish I'd kept that' list!
 

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2020 A180 Sport Exec Polar White
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Hi folks
I took my A180 out this morning for a run of nearly 40 miles including fast A roads. Just come back and the app STILL says Battery Partially Charged which I'm a bit surprised at. I was out for well over an hour as well with no heated seats etc on, just heating.

Any ideas how it can still be only partially charged or is the battery faulty? Its got 2500 miles on it, registered in May this year.

Thanks in advance!
 

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Hi folks
I took my A180 out this morning for a run of nearly 40 miles including fast A roads. Just come back and the app STILL says Battery Partially Charged which I'm a bit surprised at. I was out for well over an hour as well with no heated seats etc on, just heating.

Any ideas how it can still be only partially charged or is the battery faulty? Its got 2500 miles on it, registered in May this year.

Thanks in advance!
It's quite possible that it is not 'fully' charged but I would have thought it would be sufficiently charged not to see this message, however, I would suggest a trip to the dealers. It could be a fault with the car, the app or the battery, I just hope your dealer is skilled enough to find out which but most likely he will just charge the battery and send you on your way 🙄
 

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It's quite possible that it is not 'fully' charged but I would have thought it would be sufficiently charged not to see this message, however, I would suggest a trip to the dealers. It could be a fault with the car, the app or the battery, I just hope your dealer is skilled enough to find out which but most likely he will just charge the battery and send you on your way 🙄
Thanks, just checked the voltage on MBUX, it's constant between 14.8 and 14.9v. Stop start is automatically disabled so clearly the car thinks the charge is too low.... 🙄😒
 

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Thanks, just checked the voltage on MBUX, it's constant between 14.8 and 14.9v. Stop start is automatically disabled so clearly the car thinks the charge is too low.... 🙄😒
Sadly the volt meter on the dash only tells us the voltage the alternator is pushing out and not why. One explanation could be that because the battery needs charging the alternator is giving full charge current & voltage or it could mean that the battery is fully charged and it's just topping it up, or there could be other explanations unfortunately.

If you have a volt meter you could check the battery yourself but to get any sort of realistic reading you need to open the bonnet then lock the car for half an hour or so before taking a reading. If you get 12.3v or less it suggests the battery needs charging and if its more than 12.7v it suggests it's reasonably well charged but these modern charging systems make it very difficult to draw exact conclusions.

My dealer found a fault on my car where one of the electrical circuits was drawing current when the car was switched off and/or the battery was defective. During that time the MBUX volt meter normally showed between 12.3 & 12.8v except when I was coasting when it was 14.8v. Now with a new battery & electrical circuit reset I normally have 14.8v except after a motorway run when it's 12.9v so you can see it's difficult to figure out what the charging circuit is actually doing at any point in time.

I think you would do best to get it to a dealer and ask them to do a full investigation rather than just charge the battery for you
 

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Sadly the volt meter on the dash only tells us the voltage the alternator is pushing out and not why. One explanation could be that because the battery needs charging the alternator is giving full charge current & voltage or it could mean that the battery is fully charged and it's just topping it up, or there could be other explanations unfortunately.

If you have a volt meter you could check the battery yourself but to get any sort of realistic reading you need to open the bonnet then lock the car for half an hour or so before taking a reading. If you get 12.3v or less it suggests the battery needs charging and if its more than 12.7v it suggests it's reasonably well charged but these modern charging systems make it very difficult to draw exact conclusions.

My dealer found a fault on my car where one of the electrical circuits was drawing current when the car was switched off and/or the battery was defective. During that time the MBUX volt meter normally showed between 12.3 & 12.8v except when I was coasting when it was 14.8v. Now with a new battery & electrical circuit reset I normally have 14.8v except after a motorway run when it's 12.9v so you can see it's difficult to figure out what the charging circuit is actually doing at any point in time.

I think you would do best to get it to a dealer and ask them to do a full investigation rather than just charge the battery for you
Much appreciated thanks 😊
 

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Bizarrely enough took the car down to pick up a takeaway just now, 15min round trip with lights, heating on full and both heated seats on, battery now fully charged according to the app. o_O
 

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Bizarrely enough took the car down to pick up a takeaway just now, 15min round trip with lights, heating on full and both heated seats on, battery now fully charged according to the app. o_O
I think some have said that the app can be slow to register the correct readings, if this correct perhaps your earlier run did the trick ofter all :)
 

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My car hasn’t shown fully charged since the pandemic began. Well, that’s not quite true, it was fully charged for 2 weeks after its 1st service and I think they had to charge it in order to update to FU3. Other than that it always says partially charged but I don’t receive any warnings. I have assumed that my once a week drive of 28 miles isn’t enough - mileage/time/correct type of drive - to keep the battery at full charge. The only driving I do on top of this is the occasional down the road trip to take my parents provisions which likely does more harm than good. FYI, my stop/start is always automatically off too, presumably to ensure no overtaxing of the battery. I don’t think there’s a problem with the battery, just a lack of reasonable use. I won’t worry unless the warnings start.
 
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