If my battery is reading 12.06 Volts engine off - Is this acceptable level or a potential problem ?     Stop/ start Battery. 

I have been informed it should be minimum 12.5 V   engine off  and when engine on 14.5 Volts advised by dealer are these details correct and accurate. 

Is there an acceptable range during the winter months ?   Thank you. 

 

That battery probably won't last the winter if it's resting at 12.06 volts now.

12.5v would be nice but also unrealistic for a modern Ford.  I'd say anything over 12.2v would be alright for these.

Winter is harder on batteries but the acceptable voltage range doesn't change.

13 hours ago, PJZ said:

I have been informed it should be minimum 12.5 V   engine off  and when engine on 14.5 Volts advised by dealer are these details correct and accurate. 

 

Both these voltage values are relative because:

12.5V engine off would be good if measured when ECUs are awake and even better if that is the voltage when the brake system performs its tests (if you have the MK C1 or MK C2 brake system fitted). If this is the voltage value while car is asleep then it is ok-ish.

14.5V engine on is again relative because of the smart charging system fitted on the focus. If battery State of charge is low, then you can see 14.9V. if the state of charge is good then you might see lower that 14.5V or no charge at all.

However, 12.06V is not Ok.

Yesterday after a 100 mile round trip - engine off approx  1 hour after stationary reading 12.5 V  the following morning reading 12.1 V. 

I will check again in another few days to see on a daily basis is the battery remaining at 12.1 V early morning or if any different, thanks. 

I believe you can re-charge the battery yet what will it continue to hold /  standing voltage  perhaps at 12.1 V and if the colder winter weather will cause battery to drop even further.  This Focus is only 2 years old. 

Wife's car a VW Polo ...  used not too often never let us down over last 10 years ( low mileage ) Battery is sitting at 11.95V only checked as a comparison whilst I was checking out the Focus.   

VW is not  a stop / start battery -  Ford is a stop / start with more accessories needing electrical power. 

I did have a Focus diesel stop/start that needed a new battery after 8 years and a few starting issues due to low mileage trips. 

21 hours ago, PJZ said:

If my battery is reading 12.06 Volts engine off - Is this acceptable level or a potential problem ?

On a 2022 model, the battery in theory should still be functional although the poor quality underrated batteries fitted as original equipment rarely last more than three years.

If you measure battery terminal voltage (approximately 1 hour after parking) with a digital multimeter you will be able to compare your State Of Charge (SOC) against the following table:

Remember that your cars charging system is set to 80% by default.

Follow up ...  Ford Dealer carried out further testing etc. over a couple of days then stated all is fine as you have no error codes and no issues found.  The Battery Voltage was still low as flagged up initially by Ford dealer themselves after a recent service and that's my point Ford told me I had a problem with a low battery hence the further investigations yet when I asked again what is the acceptable battery voltage they would not commit yet their own health checks flagged this as a red warning error. As my car is just 2 years old fortunately I walked away confused and a little frustrated WHY did Ford dealer go through all this malarkey .... and waste my time and theirs for what purpose ?  If I have problems - battery related over winter I will follow up and insist the problem is resolved. 

Still under warranty yet if I had been out of warranty I would have possibly been presented with a larger bill and probably fitted a new battery ...  No real confidence how the service visit and the Ford Checklist Report stated Red Warning errors car battery is reading a low voltage and needs investigating. Did I ask too much from Ford when I asked a basic question what voltage should my car's battery be to in good condition.  

 

Based on my experience with batteries (as said, we are NOT lucky)

Have had endemic Low Battery alerts in warranty and to date,  which we now mostly ignore.
Had multiple tests using Midtronics device which only gives options such as Good, Good/Recharge, Fail and is only test they will accept for a warranty claim?
OE battery eventually was agreed by dealer to have failed within the 3 year Ford car warranty BUT they said:

OE batteries are only "guaranteed" for 1 year so we had to buy a new one (with a minor contribution from Ford)
The replacement Ford, identical battery was "guaranteed"  for 3 years (I'm using quotes because you may think it means that it will start the car reliably for that period of time BUT it may only cover manufacturing defects (less and less likely) and not things like sulphation, low capacity, inability to start as these come under "wear and tear"
When challenged on the different conditions  they stated "market demands"???

So good luck on proving that and be pleasantly surprised if a battery is replaced under warranty if it doesn't do what you would expect (however, always worth trying)

From Yuasa, they also guarantee for 1 year against manufacturing faults and reseller MAY offer a better set of conditions e.g. Halfords warrant our Yuasa for 5 years. However there are disclaimers in the tiny print but complaining may get you a new one to avoid unhappy customer syndrome or they may insist on Wear and tear or user errors.

Do let us know how you get on as it doesn't feel right - any warranty should clearly include starting the car for the time period specified regardless or they should limit the warranty period to one that they are certain that can be met?
End of rant...