Hi all,

so had focus since July, used daily for work approx 1 - 1.5hr drive each way with traffic. Last week had 2 days off, then back to work for 1 day, went out sat for short 20min drive each way then it sat there rest of sat until wed morning. Windows frosted up so started car, turned on max and scrapped side windows clear then easy to clear front window. Got back in car to see red box with 12v battery low msg.

start stop still worked on way to work then coming home and today no msgs at all.

so do you think battery issue? Should I get it checked it is it just due to cold temp and not used for couple of days? Concern is when off for Xmas would be used for 7days, will car be ok and start it will battery be flat and need new one?

never had this on previous focus just worked, even though car had battery leaking issue but still started.

thanks

kev

Get a multimeter and check the battery yourself.

On 11/26/2025 at 12:00 AM, unofix said:

There is a common misconception that driving long distances charges the battery. While that was certainly very true for cars before 2005, it most definitely is not true for newer models especially those built after 2017.

Due to ever tighter emissions regulations manufacturers were forced to do everything possible to meet impossible government targets. One trick used is to firstly only charge the car battery to a maximum of 80% of it's capacity. Secondly only use the alternator to charge the battery on engine 'overrun' ie. when slowing down, or when going down a hill. This results in the battery State Of Charge gradually getting lower and lower as the weeks go by. Long gone are the days when a 50 mile run down the motorway would recharge the battery. The 'Smart' charge systems used on most modern cars cares little for how long or how fast the car is driven, only about how much the alternator can be used to slow the engine when reducing speed and hence charging the battery with zero emissions.

 

Ok, the fact it not happen yesterday evening and today I presume means battery issue now ok or does it only alert once and doesn’t again until a certain time frame past?

I think I got a old multimeter (big one) I’ll see if that’s capable and see what it reads

Thanks

kev

If it's a 2025 year, I would report it to your Ford dealer!

 

It is, but only had it come on once, wondering if just cos sat for 4 days, then when started pressed max button to clear windows etc, since using last few days, no msgs... car doesn't do long runs, it does about 15miles each way to work which takes just over an hour with traffic each way. start stop still worked so figured cant be that low as otherwise would not work?

Thinking maybe take it on a run for couple of hours let that charge battery a bit. Not found multi meter to test with atm.

Kev

7 minutes ago, kev2011 said:

Thinking maybe take it on a run for couple of hours let that charge battery a bit.

Why not take it for a 24 hour drive around the country, that might add 3 or 4 % to the SOC ?

On 11/27/2025 at 8:55 PM, unofix said:

The 'Smart' charge systems used on most modern cars cares little for how long or how fast the car is driven, only about how much the alternator can be used to slow the engine when reducing speed

 

This happens to mine as well, after a couple of days without use.  I was initially concerned about it so went and got myself a smart charger to top up the battery.  When it's full obviously I get no more warning message.  But then after a couple of days without use, it's back again.

I don't bother about it now. It always starts well.  And I'm very happy with the car.

17 hours ago, kev2011 said:

It is, but only had it come on once, wondering if just cos sat for 4 days, then when started pressed max button to clear windows etc, since using last few days, no msgs... car doesn't do long runs, it does about 15miles each way to work which takes just over an hour with traffic each way. start stop still worked so figured cant be that low as otherwise would not work?

Thinking maybe take it on a run for couple of hours let that charge battery a bit. Not found multi meter to test with atm.

Kev

It wouldn't do any harm to have the information recorded at your dealer, in case of future problems.

My focus STline estate regularly comes up with low 12v battery notice. I took it back to the dealers who kept my car overnight to charge it, then returned it either the advice to take it out on a long run more often, wasting petrol in my opinion, when it is supposed to be more economical 

13 minutes ago, Patricia croft said:

when it is supposed to be more economical 

who ever said it was more economical ?

Get a Smart battery charger and charge the battery every 4 or so weeks if you don't use the car much.

28 minutes ago, Patricia croft said:

the advice to take it out on a long run more often

Amazing how dealers keep trotting out this line. Might have been relevant when we still had dynamos!

As I've mentioned elsewhere shorter runs with lots of slowing down, engine braking, etc are far more useful for charging, counterintuitive though it seems.

There is a common misconception that driving long distances charges the battery. While that was certainly very true for cars before 2005, it most definitely is not true for newer models especially those built after 2017.

Due to ever tighter emissions regulations manufacturers were forced to do everything possible to meet impossible government targets. One trick used is to firstly only charge the car battery to a maximum of 80% of it's capacity. Secondly only use the alternator to charge the battery on engine 'overrun' ie. when slowing down, or when going down a hill. This results in the battery State Of Charge gradually getting lower and lower as the weeks go by. Long gone are the days when a 50 mile run down the motorway would recharge the battery. The 'Smart' charge systems used on most modern cars cares little for how long or how fast the car is driven, only about how much the alternator can be used to slow the engine when reducing speed and hence charging the battery with zero emissions.

My Jan 2025 Focus was fine until Sept, then the red box charge alert starting coming up every week.  In Nov it started to repeat every could have days.  Two 4 hour journeys did hold off the message for about a week, but it's got worse again.  Sometimes the interior lights would not operate if it were too low, as it goes into a saving mode.  In the end I did some experiments by using a multimeter to measure the voltage at different times.

I charged the vehicle to 12.94V, but got an alert 3 days later

Typically the voltage would drop overnight up to 50% of State Of Charge

I also noticed that when measured after stopping, 30 min later the Voltage may go up.  I later read that the 48V Hybrid battery would charge the battery, so this rather skewed some of my results.

Anyway, I charted this all out, and reported it to the dealer.  They took it in for a day, then said they would change the battery.  That's due in a coupe of weeks, so fingers crossed

16 hours ago, GadgetMan999 said:

My Jan 2025 Focus was fine until Sept, then the red box charge alert starting coming up every week.  In Nov it started to repeat every could have days.  Two 4 hour journeys did hold off the message for about a week, but it's got worse again.  Sometimes the interior lights would not operate if it were too low, as it goes into a saving mode.  In the end I did some experiments by using a multimeter to measure the voltage at different times.

I charged the vehicle to 12.94V, but got an alert 3 days later

Typically the voltage would drop overnight up to 50% of State Of Charge

I also noticed that when measured after stopping, 30 min later the Voltage may go up.  I later read that the 48V Hybrid battery would charge the battery, so this rather skewed some of my results.

Anyway, I charted this all out, and reported it to the dealer.  They took it in for a day, then said they would change the battery.  That's due in a coupe of weeks, so fingers crossed

That is interesting information.

Please let us know how you get on after they change the battery.

Shouldn't have these problems with one year old cars (obviously!).

Yes I will do.  The car has had a few alerts recently, so today I went to charge it up, and found that the air vent cover by the battery was cracked - I'm guessing that they left a tool on top then closed the bonnet (hood).

Also, and this is very strange, when I left the garage after they did their testing, the green cruise control speed indicator on the dash has stopped displaying.  Cruise control does work though.  Anyway I dont want to send this discussion on a different route, but I'll update after my next visit on 23rd

Fords swapped out my battery with another identical one, so let's see how that goes.  

They also fixed the Broken air vent.  I was expecting a fight on this, but thankfully the dash cam captured the point the mechanic shut the bonnet on their tool, then opened bonnet to retried it.

As regard to the missing Cruise Control indicators on the instrument display, they have ordered a new instrument display - a bit surprising, but lets see.....