Is my battery on my new car compromised?

I took delivery of a pre-registered Ford Focus ST-Line X Edition a couple of weeks ago. It was registered by the dealer in Dec 2025 though I don't know how long it was sat with them. A couple of things were of concern:

1. When I got home from the dealer I had a bit more of a look around and the red plastic cover for the +ve terminal was sitting between pipework. I alerted the sales consultant together with a photo and she said it would all sort itself out when the car was driven a bit and to put the cover somewhere safe, or refit it myself.

2. Just spending a few minutes looking through the display etc the low battery warning came on, and has done so a couple of times since. I've not yet done anything other than 3-4 mile trips a couple of times a week.

Today, again the warning light came on as I was sat in the driveway trying to get to grips with the features and controls and so I decided to put my smart-charger on. When full the charger reads 5 bars. This started at 1 bar and 12.0v. After about 8hrs it was reading 3 bars and 13.6v. I can't readily leave the charger on overnight so I'll continue charging to full tomorrow.

I'm now beginning to think that the battery has been allowed to go flat. The car was originally sitting at a different site to where I bought it from and it was driven over the morning that I went to pick it up. I theorise now that the battery was flat and it was jump started, hence the battery terminal cover being removed.

My previous experience with batteries is that once they've been allowed to go flat their life is compromised. Any suggestions please as to what action I should take from here?

10 hours ago, AL26 said:

I've not yet done anything other than 3-4 mile trips a couple of times a week.

This isn't enough to charge a Mk4 Focus battery. You'll need to top it up with the Smart charger regularly.

10 hours ago, AL26 said:

can't readily leave the charger on overnight so I'll continue charging to full tomorrow.

Doesn't work like that I'm afraid. I have the same problem. You'll find the battery charge drains away overnight so it'll be much lower when you start charging again and likely to be just one bar again.

15 minutes ago, TomsFocus said:

Doesn't work like that I'm afraid. I have the same problem. You'll find the battery charge drains away overnight so it'll be much lower when you start charging again and likely to be just one bar again.

Same here. I have both a NOCO and a C-tek charger and need to let both go through the full sequence of bars/lights and on to "float" to be assured of a full charge, however long it takes.

Even then, I've found with two Mk 8/8.5 Fiestas over the last 7 years a regular "top up" is needed.

There are numerous threads on the issue on Focus/Puma/Fiesta forums on here. Because of the "intelligent" (haha!) charging systems in modern cars it quickly reverts to the default state of charge (SOC) of 80%.

Some owners have increased the SOC to 95% using Forscan.

Thanks Tom and Eric for your comments.

My main concern however is whether the battery life is likely to have been compromised by possibly having been left to go flat at the dealer's yard prior to my taking delivery.

6 minutes ago, AL26 said:

My main concern however is whether the battery life is likely to have been compromised

A long gap between build and delivery to customer is not particularly unusual.

The battery is covered by warranty for 3 years, nowadays you seem to be doing well if you get longer than that out of it anyway!

9 minutes ago, AL26 said:

Thanks Tom and Eric for your comments.

My main concern however is whether the battery life is likely to have been compromised by possibly having been left to go flat at the dealer's yard prior to my taking delivery.

Maybe but battery life is only about 3-4 years nowadays anyway. The majority of brand new cars do have be jump started in the compound so that's not unusual.

My personal experience is that my Mk4 was in deep sleep mode from the moment it was delivered. The battery went completely flat just once (down to about 2v iirc!) but I jump started it, ran it for a bit and it never went flat again. So I'd have to say the battery wasn't compromised by that event. But it continued to be in deep sleep mode from then on. Just have to accept that when doing infrequent and short journeys with a modern Ford.

It's going to take me a few weeks to get used to not having a standard non-computer controlled car after 60yrs of standard petrol IC vehicles. It is sounding as though I'm worrying unnecessarily, though I'm disappointed that in the week from ordering the vehicle to picking it up a bit of tlc wasn't carried out, namely a full charge to the battery and setting tyre pressures back to normal.

After this morning's 4 hour charge the battery is steady on 13.2v and full 5/5 bars. I've not seen it below 12v and 1/5 bar charge so it seems as if deep sleep mode could have done its work. I'm not sure I consider needing to charge the battery if the car is only used lightly and not used for a few days as being very green if 3-4 yrs is the likely lifespan. My Mark2 I'm sure only had one battery change in the 15yrs I had it. But then I'm of an era that was sad to see the starting handle disappear 😀

Undoubtably I'll be back with more questions on other questions as I "learn" the car.

Welcome to Focus Mk4 ownership!

We have two mk4.5’s in the family and both were delivered with battery warnings. Clearly Ford don’t charge them before handover, TBH they seem to do the bare minimum for everything despite the eye watering service costs!

We got away quite well with 2 years before having to break out the chargers despite mostly short journeys, though I’ve upgraded to the Yuasa 096 battery in the parents Focus as it moves maybe twice a month 🙈. My own Focus is literally on charge as we speak.

2 hours ago, AL26 said:

My Mark2 I'm sure only had one battery change in the 15yrs I had it. But then I'm of an era that was sad to see the starting handle disappear 😀

Yes, that was very much my sort of experience until fairly recently. My wife's car is 12 years old and still on its original battery, despite doing low mileage. Still on the original.key fob battery also (another frequent hassle with newer cars.)

My first Ford (Mk 1 Cortina) still had a handle and very reassuring it was too!

My Mk2 had a new battery within the warranty period. (2010 Ford battery in a 2008 car). I bought it at 6 years old and often wondered why. That battery then died at 10 years old when I stopped driving it for a few weeks due to buying a Mk3.

I also bought another Mk2 that was on its 4th battery in 12 years! (Based on receipts). Though tbf that one had keyless entry, and I don't think that was programmed particularly well on Mk2s, wasting additional power while parked.

11 minutes ago, Eric Bloodaxe said:

Still on the original.key fob battery also

That really is impressive! Even on older cars I remember changing the fob batteries at around 10 years!

If we had to fully charge the 12v battery's of the cars and vans we see , there would be a queue a mile long waiting to charge 200 vehicles a day. Normally the battery does charge sufficiently from inspection to delivery.

2 hours ago, TomsFocus said:

That really is impressive! Even on older cars I remember changing the fob batteries at around 10 years!

Yes, find it hard to believe myself. Even when it does go, its still a bladed key that goes into a proper keyhole so no messing with emergency keys, etc. I unlock it manually anyway when I use the car to keep things working.

Our battery experience says that the only way Ford will change a battery is if their approved tester (was Midtronics) clearly sates "Replace" and this is usually after a full charge.
Ours was agreed to be faulty just outside the 3 years from new and we had to buy a new Ford one with a contribution and pay the difference. This had the regular "Low Battery" alert on the dash which is never satisfactorily explained
The battery must also be within its warranty period which (2011) was 3 years from new.
However, at that time, replacement Ford batteries were only warranted for 1 year (we were told "market demands")
AND the warranty only covers (increasingly rare) manufacturing faults it does not cover your expectation (maybe) of it being able to start and operate the car for the stated warranty period.

So even buying any replacement battery with a 5 year or other period, doesn't give you the protection you may assume.
Please feel free to give any supplier that does give what you may expect in their warranty terms or changes to what I have said above.

This is a standard car today, and it has been for a number of years now. It is necessary to buy a smart battery charger and to use it if the car only does short trips. The old method of a thirty minute drive to charge the battery is no longer valid because with the price of fuel and concern for the rock we live on, manufacturers use every trick to wring more miles and less CO2 out of your car so they turn the alternater off when the computer says it isn't needed. (Note for the techies: I must admit to thinking a manual changeover field coil switch would be a good dodge on one of these so it would charge when I wanted it to...)

The car uses a lot of battery power for half an hour after switch off, as it recalibrates itself, analyses knitting patterns and talks to the mothership but that is the way it is. Today's battery is charged at very much higher currents than in days of yore when a 45 Amp Alternator was considered a big upgrade over the dynamo in your Mk 1 Cortina. Infotainment electric windows, central locking , ABS, Engine management and the heated front screen, Stability control, electric power steering, parking sensors and several cameras, cruise control and the three radar systems, Crash avoidance, lane control and electric heated folding mirrors, seat and steering wheel heaters all consume current. The modern alternator needs to provide at least double what the older ones did and the battery itself has a limited recharge rate. (This, incidentally is why a Formula one car uses a 40 Kg battery when calculation suggests that a 10 Kg one should do. Those who decry the current formula need to realise that the effort going into radically improving recharging rates without blowing up the battery will trickle down to road cars which will go further on a minute's charge as the technology improves.)

The original battery in my Fiesta titanium lasted seven years before becoming unreliable. I am surprised and delighted with that. They used to need replacing every two years back in the Cortina days.

I too have had this issue. Bought a 2024 ST Line X (16 months old) at the weekend and yesterday had the low battery warning. It's on charge now using a CTEK charger so hoping this fixes it

Dealer told me to put some charge in every few weeks just to be on the safe side

Since I did my charge (in two sessions) the display happily shows "Full accessory charge available" or similar when ignition is turned on.

There seems something rather perverse that after years of quite reliable batteries negating the need of olden days for a battery charger except in emergencies we are now expected to have a smart charger for modern cars. They might just as well build one in and provide a mains socket and I have no idea how my wife/sister etc would cope. Just call breakdown services I guess.

I will say that my "top of the range" £9.99 purchase of a charger in 2020 from Aldi "Auto XS Car Battery Charger" has worked well in this situation. Bought because in lockdown both cars were sitting unused in the driveway.

I have a mk4 (72 plate) Focus ST Line and from new i had the occasional low battery warning and sometimes the infotainment screen failed to come on when it was cold outside. I checked the battery voltage and it was only around 12v. I thought my volt meter was telling me lies as this was a relatively new car. I eventually took it to the dealer who replaced the battery and battery tray because the battery had leaked. All this was done under warranty so I have no complaints and I have had no other issues since. I would say though that I think the battery is very small considering the stop/start requirements