[RS3100]

As above, if you connect anything directly to the battery negative terminal you will upset the battery monitoring system.

My useless local dealer did that with the battery maintainer whilst servicing my car, despite VIDA instructions to the contrary, and start/stop was unavailable when I picked it up. According to VIDA, the BMS should resync if the car is left parked and all doors shut and locked for 6 hours. I found that start/stop was working again the following day after the car had been parked overnight, but it's easier to just avoid the issue!

 

[Suds]

Over the last month or so I started to notice that the "Stop/Start" isn't as active as it normally is on the same journeys, I just put this down to the system holding off due to engine temp or not enough miles since starting the journey, I don't do a lot of mileage from the house to work.

Anyway, last week I took a spin down to the local shops and when I switched off the engine and opened the door a warning message popped on the screen that said "Low Battery Charge", this is the first time in four and half years since owning the car from new that I've seen this ?

The message came on again when I arrived home and again the following morning, however, it has now stopped appearing over the last 4-5 days, but I've now noticed that the "Stop/Start" is not activating at all, and in the "My Car" menu it says "Stop/Start Not Available" ?
Obviously this is linked to the "Low Battery Charge" warning but if this warning message has now ceased why is the "Stop/Start" still not available ?

I've checked the battery with a multimeter and it shows as 14v with the engine ticking over and 12v with the engine switched off.
I was then thinking that perhaps the battery is not holding it's full charge and maybe I should leave it overnight before checking it on a cold engine, which I've done this morning, but it's still showing 12v !

Apparently there are 2 batteries on the V40 but I can only get access to the main one in the engine compartment, could I be checking the wrong one ?


Any advice appreciated.
Thanks

I've just had the same issue on my 2015 V40 T5 R

Over the last month or so I started to notice that the "Stop/Start" isn't as active as it normally is on the same journeys, I just put this down to the system holding off due to engine temp or not enough miles since starting the journey, I don't do a lot of mileage from the house to work.

Anyway, last week I took a spin down to the local shops and when I switched off the engine and opened the door a warning message popped on the screen that said "Low Battery Charge", this is the first time in four and half years since owning the car from new that I've seen this ?

The message came on again when I arrived home and again the following morning, however, it has now stopped appearing over the last 4-5 days, but I've now noticed that the "Stop/Start" is not activating at all, and in the "My Car" menu it says "Stop/Start Not Available" ?
Obviously this is linked to the "Low Battery Charge" warning but if this warning message has now ceased why is the "Stop/Start" still not available ?

I've checked the battery with a multimeter and it shows as 14v with the engine ticking over and 12v with the engine switched off.
I was then thinking that perhaps the battery is not holding it's full charge and maybe I should leave it overnight before checking it on a cold engine, which I've done this morning, but it's still showing 12v !

Apparently there are 2 batteries on the V40 but I can only get access to the main one in the engine compartment, could I be checking the wrong one ?


Any advice appreciated.
Thanks

Just had this same issue on my 2015 V40 T5R, main battery tested fine on a standard battery tester but a deeper test revieled at full charge the battery was only giving a reading of 530 cold crank instead of the rated 760 for a new battery. I was told it had enough to drive it normally but the start stop function would not operate and I'd continue to get low battery warnings. I replaced the main battery and have had no problems since.

 

[Driven]

Four and a half years, battery life over ☠
Get a NEW battery and forget all this charger discussion.

 

[jactac]

Sorry but I tend to disagree.
The service manager at my dealership advised a couple of lengthy runs in the car, would cure the problem, which it has, but not permanently due to the low mileage in general that I do, and this seems to be the overall opinion of other owners.

My issue is short journeys that I do and the battery not getting enough charge, the battery itself is fine.
The car gets used about 4 days a week, with an average of 6 miles a day, Friday through to Tuesday it's just sitting on the drive, so maintaining the battery via a good quality "smart" charger/maintainer every now and then seems to be the answer.

I think in time the same would happen again, even with a new battery, if the mileage is not put on the car.

 

[jactac]

Just purchased the Noco Genius 10 from Halfords.
Retails at around £120 but with trade discount had it for £90.
My old charger was on its last legs anyway, plus it was easily around 20 years old if not more, so I'm guessing it might of caused more problems than good if I tried using it on these newer type Stop/Start batteries.

NOCO - 10-Amp Smart Battery Charger - GENIUS10

The GENIUS10 is a 10-amp battery charger, battery maintainer, and battery desulfator for 6-volt and 12-volt batteries.

no.co

 

[Kepete1]

Have had similar porblems with my battery over the winter.
Sometimes get the "Low battery" warning. Mostly I recognise that Start/stop is not working anymore as it used to.
I have charged my battery directly from the + and - ports of the battery(not chassis, didn't know about that).
After recharging it, the start/stop was working fine for few days, then again will not start to turn off.

Without thinking any further, next step will be to replace the battery. Late 2015 year car, so a bit early to replace it already. But seems that start/stop system also stresses the battery.
At least a battery is quite inexpensive compared to other car parts and one of the parts that is easy to fit yourself even without any technical knowledge

 

[Kepete1]

Four and a half years, battery life over ☠
Get a NEW battery and forget all this charger discussion.

Sorry but I tend to disagree.
The service manager at my dealership advised a couple of lengthy runs in the car, would cure the problem, which it has, but not permanently due to the low mileage in general that I do, and this seems to be the overall opinion of other owners.

My issue is short journeys that I do and the battery not getting enough charge, the battery itself is fine.
The car gets used about 4 days a week, with an average of 6 miles a day, Friday through to Tuesday it's just sitting on the drive, so maintaining the battery via a good quality "smart" charger/maintainer every now and then seems to be the answer.

I think in time the same would happen again, even with a new battery, if the mileage is not put on the car.

I actually kind of agree with what Driven said, from my experience. I also drive quite low miles a day(about 10-12 miles), with windshield heaters, seat heating and all other consumers fully on.
Has never been a problem with the start/stop before, now the first winter experience this. My bet is on changing the battery to a new one and you will have next 4-5 years without problems. Charging it every week seems to be more annoying for sure.

 

[jactac]

A decent smart maintenance/charger will automatically recognise how much to top up the battery by to keep it in peak condition.
Purchasing a new battery seems a bit pointless, especially if a test confirms there's nothing actually wrong with the battery or alternator apart from the battery needing a good charge and a maintenance routine.
Personally I see no hassle in putting the battery on a trickle charge for an afternoon every couple of months to keep it at its max performance..

 

[hullu]

A solar panel trickle charger connected to the OBD socket solved my similar low battery message problem.

 

[snowman]

A decent smart maintenance/charger will automatically recognise how much to top up the battery by to keep it in peak condition.
Purchasing a new battery seems a bit pointless, especially if a test confirms there's nothing actually wrong with the battery or alternator apart from the battery needing a good charge and a maintenance routine.
Personally I see no hassle in putting the battery on a trickle charge for an afternoon every couple of months to keep it at its max performance..

Don't think just an afternoon will be long enough for a smart charger to bring a low battery back to full charge,mine used to take day and half,they not designed as a fast charger,they test charge and maintain the battery,used to just put mine on overnight or a weekend.

 

[jactac]

A weekend for me is fine, bloody thing dont get used enough so its just sitting there most weekends.
At the moment though everything is fine, seems as though that little run up and down the motorway put the charge back into it.
I'm now waiting like an excited kid to use my new "smart" toy !!!

 

[snowman]

A weekend for me is fine, bloody thing dont get used enough so its just sitting there most weekends.
At the moment though everything is fine, seems as though that little run up and down the motorway put the charge back into it.
I'm now waiting like an excited kid to use my new "smart" toy !!!

Neither does ours,the wife potter's about a bit and I mostly ride my Tiger 800,modern charger deals with both so if away I just leave it connected.

 

[Bunny]

Neither does ours,the wife potter's about a bit and I mostly ride my Tiger 800,modern charger deals with both so if away I just leave it connected.

I think I’ve learned a good lesson to make sure that the car is locked.if not the car draws power just sitting there.

 

[snowman]

Thought everything turned it's self off after a set time ?,when been updating maps via usb I have to keep popping out to hit the power button,or just leave it to carry on while driving.

 

[RS3100]

Thought everything turned it's self off after a set time ?,when been updating maps via usb I have to keep popping out to hit the power button,or just leave it to carry on while driving.

Certain systems like the radio/IHU are programmed to turn off after a certain time if the engine isn't running to save battery power. Some systems will go into low power mode or switch off temporarily if start/stop has cut in and the car hasn't restarted for a period of time.

Generally though, as with all modern vehicles, a full sleep mode to minimise battery drain is only initiated when certain conditions are met. This usually involves switching off the engine and removing the key from the vehicle, ensuring that all doors are shut and sometimes also locked, after which the various network busses will start sending various ECUs to sleep after a short time, usually about 3 to 5 minutes. How far they are powered down dpends on the type of ECU. The locking system for instance needs to be capable of detecting the key to allow you to unlock the vehicle at any time ;-)

On my Ducato van, it is necessary to follow that procedure after reprogramming ECUs to ensure that they reset correctly, and Volvo also describe it as being required to allow the battery monitoring system to reset for instance, although in that case requiring the vehicle to be left locked for 6 - 8 hours to allow the system to resync correctly

 

[jactac]

Sods law, since getting the smart charger I've not had the "Low Battery Charge" message.
Be nice to give it a go just to see how well it functions.

 

[snowman]

Just stick it on,won't do any harm.

 

[Bunny]

Just stick it on,won't do any harm.

I’ve just bought the Ctek charger and put it on and left it seams to be a good bit of kit doesn’t even get hot or buzz just some led lights on.

 

[Don Horsey]

Really !
I think you've nailed my problem !
How would I now if its the actual battery not holding a charge or the alternator not putting out enough charge ?

Alternators usually work, or fail! A working alternator should give 14.7 v. at the battery at about 1000 RPM.

 

[HPsauce]

My car strangely came up with the "Low Battery" warning the other day, less than an hour after I'd collected it from the dealer after it's 4-years-old annual service last week.
I'd driven home (about 4 miles) and parked, then returned to the car soon after to program in a SatNav destination for the next day, so I didn't actually start the engine. Not sure if I turned on the ignition or just the Sensus system.
After at most 1 or 2 minutes the low battery warning appeared and said the navigation system would turn off. Normally it would run for 15 or 20 minutes in such conditions.

I started the engine then and finished the task, the car wasn't driven at all until the next day. Subsequently I've not seen the message at all. Makes me wonder what the dealer did and whether sitting overnight reset the battery management?