Phoned my nearest Ford service agent 1st thing, they said it would be a week before they could look at it, but suggested calling Ford assistance as the car is under 12 months old. I did, the AA arrived, turned on the car and no warning light or problem appeared, he checked the battery and systems, no fault. If it happens again I will take a picture.

On 11/10/2023 at 7:58 AM, magic14 said:

Well just a little update... 

After getting back the car the other week it wouldn't get out of deep sleep mode no matter where i drove, making sure everything was off like heated seats etc... Driving like miss daisy to try and boost the charge and watching the monitor like a hawk 😂...

So charged it up for 14 hrs... Lasted 2 days before remote features disabled 🙄

Then this Wednesday morning took it off charge after charging for 23 hours... 

This morning... Deep sleep mode so didn't even last 48 hours 

Only just over a week before it is booked into go back... Typically it's coincided with the drop in temperature so I have to freeze to death every morning as limited heating 😫

Safe to say the glove box light staying on isn't the main cause of the issue like Ford was hoping as it's been disconnected yet the problem has gotten worse. 

Any recent updates on your situation? I have a 2022 Focus MK4.5 and I've had all the same issues as you the entire time i've had the car. I could do a 200 mile drive and as soon as I turn the car off it will go into deep sleep..

I recently caved in and bought a Yuasa YBX7096 battery (at my own expense) yet to fit it though. I imagine this will just prolong times between deep sleeping and normal function and not fix any underlying issues. My main gripe with all this is that my air conditioning does not get cold when the car has been started from deep sleep mode.. and with another hot summer around the corner I can't bear not having any air conditioning.

I got the car brand new in July 2022 and I took it back to the dealer in December that year complaining about this issue and they just replaced the battery which gave me 6 weeks or so of normal functioning before going back to deep sleeping constantly. Strangely my start-stop has always worked but I turn it off as soon as I get in the car so I don't know for sure if it has ever been disabled mid drive. Loads of other people online reporting this issue yet still no-one seems to really know what the issue is here..

8 minutes ago, Gus T said:

Any recent updates on your situation? I have a 2022 Focus MK4.5 and I've had all the same issues as you the entire time i've had the car. I could do a 200 mile drive and as soon as I turn the car off it will go into deep sleep..

I recently caved in and bought a Yuasa YBX7096 battery (at my own expense) yet to fit it though. I imagine this will just prolong times between deep sleeping and normal function and not fix any underlying issues. My main gripe with all this is that my air conditioning does not get cold when the car has been started from deep sleep mode.. and with another hot summer around the corner I can't bear not having any air conditioning.

I got the car brand new in July 2022 and I took it back to the dealer in December that year complaining about this issue and they just replaced the battery which gave me 6 weeks or so of normal functioning before going back to deep sleeping constantly. Strangely my start-stop has always worked but I turn it off as soon as I get in the car so I don't know for sure if it has ever been disabled mid drive. Loads of other people online reporting this issue yet still no-one seems to really know what the issue is here..

On the MHEV I’m pretty sure the lithium battery is used for stop start so not related to 12V SoC. 

33 minutes ago, Gus T said:

Any recent updates on your situation? I have a 2022 Focus MK4.5 and I've had all the same issues as you the entire time i've had the car. I could do a 200 mile drive and as soon as I turn the car off it will go into deep sleep..

I recently caved in and bought a Yuasa YBX7096 battery (at my own expense) yet to fit it though. I imagine this will just prolong times between deep sleeping and normal function and not fix any underlying issues. My main gripe with all this is that my air conditioning does not get cold when the car has been started from deep sleep mode.. and with another hot summer around the corner I can't bear not having any air conditioning.

I got the car brand new in July 2022 and I took it back to the dealer in December that year complaining about this issue and they just replaced the battery which gave me 6 weeks or so of normal functioning before going back to deep sleeping constantly. Strangely my start-stop has always worked but I turn it off as soon as I get in the car so I don't know for sure if it has ever been disabled mid drive. Loads of other people online reporting this issue yet still no-one seems to really know what the issue is here..

Hi Gus,

On MHEVs the 48V battery is supporting the Start/Stop, so unless the SOC of this battery is low, your Start/Stop shall function even if you get the Deep Sleep message.

When the engine stops due to the Start/Stop feature, the 48V battery supplies the entire car electronics (reading the BMS current flow with Forscan this can be seen). So again the 12V battery is in fact charged by the 48V battery via the DCDC converter.

The AirCon stops engaging when the 12V battery SOC is below 50%. This thing I really don't understand, because the aircon can function only when the engine is running so the SOC of the 12V battery should be irrelevant since the BISG supplies the energy while the engine is running. The BISG's rated power is enough to supply all electronics and to charge the battery, but it is the charging control which decides how it delivers the power.

Now regarding the 12V battery SOC calibration which is said the be carried out when the current draw falls below 100 mA. My car constantly stays 10-12 hours (evening till morning) without being opened. I have tested the sleep current draw and it is around 30-40mA. During sleep the battery voltage (after charging it) was 12.69 V, which according to the voltage chart @unofix posted many times results in more than 80% SOC, BUT, the SOC has not been recalibrated and is still 48-50%. I left the car for more than 72 hours unlocked and nothing. So I think the recalibration information is incorrect and the SOC is being updated some other times, but I cannot figure out when. For sure recalibration is performed after disconnecting and reconnecting the battery, this I have tested and confirmed. But this is not practical.

I too have ordered the 7096 and I hope after installing it and performing the BMS reset, things will go back to normal. I never had any issues for 3years and 3 months, until I took it to Ford for the 60k km service, and these issues appeared afterwards. I am pretty sure the battery got severely discharged and possibly some cell damage happened...

 

3 minutes ago, RaduF86 said:

Hi Gus,

On MHEVs the 48V battery is supporting the Start/Stop, so unless the SOC of this battery is low, your Start/Stop shall function even if you get the Deep Sleep message.

When the engine stops due to the Start/Stop feature, the 48V battery supplies the entire car electronics (reading the BMS current flow with Forscan this can be seen). So again the 12V battery is in fact charged by the 48V battery via the DCDC converter.

The AirCon stops engaging when the 12V battery SOC is below 50%. This thing I really don't understand, because the aircon can function only when the engine is running so the SOC of the 12V battery should be irrelevant since the BISG supplies the energy while the engine is running. The BISG's rated power is enough to supply all electronics and to charge the battery, but it is the charging control which decides how it delivers the power.

Now regarding the 12V battery SOC calibration which is said the be carried out when the current draw falls below 100 mA. My car constantly stays 10-12 hours (evening till morning) without being opened. I have tested the sleep current draw and it is around 30-40mA. During sleep the battery voltage (after charging it) was 12.69 V, which according to the voltage chart @unofix posted many times results in more than 80% SOC, BUT, the SOC has not been recalibrated and is still 48-50%. I left the car for more than 72 hours unlocked and nothing. So I think the recalibration information is incorrect and the SOC is being updated some other times, but I cannot figure out when. For sure recalibration is performed after disconnecting and reconnecting the battery, this I have tested and confirmed. But this is not practical.

I too have ordered the 7096 and I hope after installing it and performing the BMS reset, things will go back to normal. I never had any issues for 3years and 3 months, until I took it to Ford for the 60k km service, and these issues appeared afterwards. I am pretty sure the battery got severely discharged and possibly some cell damage happened...

 

Hey, thanks for the detailed information!

Let's hope the new batteries give us some peace 😂

I went to replace mine yesterday and only then realised that the battery clamp bracket on my model is different to all the models I have seen in video tutorials.. one side of the clamp is secured much deeper into the chassis (it runs down the side of the battery) and so I now have to source an extension socket bit. My car is in for it's first service (2 year mark) in July and I am now wondering if it's worth putting in the new battery before then as I don't want the dealer kicking off for whatever reason 🧐 😂

Yes, the clamp does have one nut for which an extension socket is required. However, in my car it seems that nut can be left alone because the only way to remove the battery is to slide it towards the car's nose. Therefore, the air filter box must be removed. Of course I have found this the hard way, I first disconnected the battery, then removed the clamp, then I tried to lift it. But the battery tray doesn't let it lift, only slide forward.

By the way, does anyone know how to remove (without damaging) the clips securing the wire for the MAF sensor? I couldn't remove them so it was pretty difficult to remove the airbox.

I believe you should be fine changing it before your first service. IN my case the car was in for 3 days due to some warranty work besides the oil and filter change. So I suspect it stayed awake for a long time so the battery drained. This should not be the case for a normal first service.

 

Turns out I was wrong and the down low nut does need to be untighten or removed.

Anyways, I installed the Yuasa today and the voltage difference is quite big. Clearly the old Varta was at the end of its life.

I have found something interesting and strange at the same time and I wonder if anyone around here knows why this is happening and/or if it is the same for all Fords.

So:

1. I connected the battery, hooked up Forscan and SOC = 99% Excelent!

2. Next BMS reset => All info was reset (battery service life number of start stops, cumulative discharge etc.

3. Started engine aaaand no charging. Current draw of about 21 Amps!

My Jaw dropped. So I thought ok, the Smart charging does not want to keep the battery at 99% and will discharge it to around 80%

4. I fool around, check air conditioning, steering wheel sensor calibration etc.

5. Because it got pretty warm inside, I increased the blower speed to 6 while I was again at the BCM stream and surprise:

6. I stop the AC, the battery is still charging. I set the blower to 5 and still charging, set it to 4 and it stops charging!?

This is with engine running but at standstill. Not sure what it does during driving.

So is this blower speed 5 something like a hack? Charging mode? Has anyone seen this before? Is it the Smart charging or I actually have a problem.

Can we keep our batteries properly charged by driving while having noise inside from that fan? Could it be so easy? :)))))

With the old battery the voltage was always 14.5V or above because of the very low SOC. But there was around 1 Amp being pushed into the battery which now in fact makes sense because the battery was almost dead.

So I don't know if this new behaviour is normal or not. What do you guys think?

Thanks!

All of that behavior of the charging system is normal.

Change the factory set SOC from the 80% default and increase it to 95% which will help keep the battery SOC healthy for much longer.

14 hours ago, unofix said:

All of that behavior of the charging system is normal.

Change the factory set SOC from the 80% default and increase it to 95% which will help keep the battery SOC healthy for much longer.

Is there a recommended cable for the OBD link to use with Forscan? I am assuming the cheaper bluetooth connectors are not recommended? I am very new to Forscan but am keen to increase my SOC on the new battery to 95%

Use the vLinker products: NOTE only the Windows version can make programming changes.

On 4/7/2024 at 8:59 PM, unofix said:

FORScan (for use with Windows Laptop) : https://forscan.org/download.html

It's what many Ford owners use including some Ford technicians.

vLinker FS, cable for laptop: https://www.amazon.co.uk/Vgate-vLinker-Adapter-FORScan-MS-CAN/dp/B0952P4MLP

vLinker FD, for android phone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H82WC8L

vLinker FD+, for iPhone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H8JHWP2

 

4 minutes ago, unofix said:

Use the vLinker products: NOTE only the Windows version can make programming changes.

 

Thanks so much, have bought the cable for windows laptop. Do you know if altering the SOC to 95% voids the warranty? Car is in for its 2 year service in July and I am worried they will kick up a fuss if I have swapped the battery as well as altered the SOC..

1 minute ago, Gus T said:

I am worried they will kick up a fuss if I have swapped the battery as well as altered the SOC..

They have no records of what battery is fitted and by who. If another Ford dealer changed the battery or even someone like the RAC in an emergency they would not know or even care.

Changing the SOC to 95% is very unlikely to be seen by the dealership. They do not check software or even check for updates to fix bugs so unless you point it out to them then there is no chance they would know.

6 minutes ago, Gus T said:

Thanks so much, have bought the cable for windows laptop. Do you know if altering the SOC to 95% voids the warranty? Car is in for its 2 year service in July and I am worried they will kick up a fuss if I have swapped the battery as well as altered the SOC..

As long as you fit an EFB battery the same capacity or larger it won’t affect the rest of the car warranty. (Assuming you didn’t break something in the process of changing it ofc). 
 

They won’t detect the change to the SoC. Fords server doesn’t verify the config on the car is the same as the asbuilt. Worst case if you get the BCM replaced under warranty it will be put back to 80% and you’ll need to reprogram it. 
 

Changes are made to the cars config all the time. If you’d asked for a feature to be disabled or have a tow bar fitted etc. It won’t then match asbuilt. 

3 minutes ago, unofix said:

They have no records of what battery is fitted and by who. If another Ford dealer changed the battery or even someone like the RAC in an emergency they would not know or even care.

Changing the SOC to 95% is very unlikely to be seen by the dealership. They do not check software or even check for updates to fix bugs so unless you point it out to them then there is no chance they would know.

 

1 minute ago, alexp999 said:

As long as you fit an EFB battery the same capacity or larger it won’t affect the rest of the car warranty. (Assuming you didn’t break something in the process of changing it ofc). 
 

They won’t detect the change to the SoC. Fords server doesn’t verify the config on the car is the same as the asbuilt. Worst case if you get the BCM replaced under warranty it will be put back to 80% and you’ll need to reprogram it. 

Thank you both! Appreciate the info 👍

On 5/17/2024 at 9:16 PM, RaduF86 said:

Turns out I was wrong and the down low nut does need to be untighten or removed.

Anyways, I installed the Yuasa today and the voltage difference is quite big. Clearly the old Varta was at the end of its life.

I have found something interesting and strange at the same time and I wonder if anyone around here knows why this is happening and/or if it is the same for all Fords.

So:

1. I connected the battery, hooked up Forscan and SOC = 99% Excelent!

2. Next BMS reset => All info was reset (battery service life number of start stops, cumulative discharge etc.

3. Started engine aaaand no charging. Current draw of about 21 Amps!

My Jaw dropped. So I thought ok, the Smart charging does not want to keep the battery at 99% and will discharge it to around 80%

4. I fool around, check air conditioning, steering wheel sensor calibration etc.

5. Because it got pretty warm inside, I increased the blower speed to 6 while I was again at the BCM stream and surprise:

6. I stop the AC, the battery is still charging. I set the blower to 5 and still charging, set it to 4 and it stops charging!?

This is with engine running but at standstill. Not sure what it does during driving.

So is this blower speed 5 something like a hack? Charging mode? Has anyone seen this before? Is it the Smart charging or I actually have a problem.

Can we keep our batteries properly charged by driving while having noise inside from that fan? Could it be so easy? :)))))

With the old battery the voltage was always 14.5V or above because of the very low SOC. But there was around 1 Amp being pushed into the battery which now in fact makes sense because the battery was almost dead.

So I don't know if this new behaviour is normal or not. What do you guys think?

Thanks!

Out of interest, did you get anyway with this or just default to not using fan speed 4 🤣

Hello,

What I did was to track the behaviour for a while. My main worry was that the smart charging will let the battery drain way below the 80% SOC target. But I found that this does not happen, and the battery rests between 77%-80%. The Yuasa is indeed very good so far and I never got another deep sleep since I have changed it. Remains to be seen how it holds up in time.

My conclusion is that I can use the car normally, and not care about the blower speed nor battery  state of charge as long as the smart charging is not buggy and there is no high drain during sleep. And it seems that my car has none of those issues. What I am not sure about is how battery life is affected if it is always kept between 75 and 80%. Time will tell

1 minute ago, RaduF86 said:

Hello,

What I did was to track the behaviour for a while. My main worry was that the smart charging will let the battery drain way below the 80% SOC target. But I found that this does not happen, and the battery rests between 77%-80%. The Yuasa is indeed very good so far and I never got another deep sleep since I have changed it. Remains to be seen how it holds up in time.

My conclusion is that I can use the car normally, and not care about the blower speed nor battery  state of charge as long as the smart charging is not buggy and there is no high drain during sleep. And it seems that my car has none of those issues. What I am not sure about is how battery life is affected if it is always kept between 75 and 80%. Time will tell

Thanks for the follow up, have you been tempted with changing the SOC to 90 or 95%

I'm tempted to get a Yuasa battery instead of going to the Ford garage again. 

You are welcome. Tempted yes! However, there is a big difference between the Yuasa and the Varta, so, at least for now, i do not find the need to change the SOC target. If the Yuasa lasts also for 3 years only, I shall revisit the thought of rising the SOC target.

 

Hi all,

I know this is an old topic, covering countless Ford models (including Fiesta, Kuga, who knows how many others). I noticed that the most common approach on the battery drain issue seems to be the "replace the battery with one made by Yuasa and change the SOC target". 
However, I have some additional information that I've never seen discussed before, and I think it worth being shared.

I own a 2024 Active X mHEV, which is affected by the "12V Battery low" issue since the first month. In my case. I won't dive into the relation with the service/dealer etc, it is irrelevant, they operated by he book provided by the mother company and, obviously, nothing wrong was found, for a few months. However, when the car reached the age of about 9 months, one of their battery tests indicated that the original 12 battery needs to be replaced. I want to underline this, that the battery reached an "no longer usable" rating from a certified Ford service unit after 9 months of ownership. Let's label this piece of information as A.

I've also learned about the glove box button issue (which doesn't break the contact every time), it was affecting me as well, but this is a small issue, because the glove box light power is cut after a few minutes after locking the car. This light doesn't stay lit for sufficient time to discharge the battery. 

The attempt to identify the root cause

I spend some time building a least-intrusive voltage logger solution, to find out what is happening, using a quite short sampling interval (1-5 seconds), which I've kept connected to the battery for extended periods of time, powered by an alternate battery. I wasn't able to make an accurate current logger, this would have become too intrusive, which I've avoided, therefore I've only relied on voltage information.

Taking the voltage into account, and the chart provided by @unofix, this logger provided interesting information, like a drop in voltage recurring once every hour when the car was parked, with the duration of 6 minutes on every occurrence. By doing some math, I ended up with the conclusion that the voltage drop can only be created by an electrical load of about 10 amps, and the drop was recurring with sufficient precision to consider this something which a) it is very likely controlled by software and b) operating on schedule, as programmed.

When does this thing stop? This recurring pattern ends when the battery reaches the "12V battery low" state, as a measure of protection. Again , this makes me think that what happens there is controlled entirely via software. It worth noting that there are exceptions from the pattern, in certain cases there is no recurring voltage drop every hour. I have no idea why. But, as a rule of thumb, the recurring voltage drop occurs more than half of the total time when the car is parked. The effect of this programmed activity is that the battery loses about 50% of its charge in less than two days. Let's label this piece of information as B. 

I wasn't able to find any link between this and other software/remote related settings. Turning remote start on and off didn't change anything, I also made an attempt to disable communications entirely, that didn't help as well. However, I have an active subscription for FordSecure (let's call this piece of info C)and real time maps, I believe these services are blocking the complete deactivation of all remote services.

Putting the things together

What matters here is that, from info A and B we can understand

• why the original batteries die very quickly - e.g. less than a year, instead of 4+. The programmed load wipes out discharge cycles out of the battery at a much higher rate, thus making the battery reach it's charge/discharge cycle count much faster. The problem doesn't seem to be caused by the accumulators, as much as it could be caused by excessive discharge, because of inefficient programming. 
• that replacing the battery with a larger one and setting the target SOC at a higher value doesn't solve the issue, it only makes it less visible. 

I suspect that FordSecure (C) could be the culprit, I work with software, and I think that it is very likely that a function like FordSecure reporting could be related to a recurring task running on the car.  I also know that the car is calling back home, as part of the 'Remote Features', and it does more things than we can see on the app dashboard. For example, I'm only able to see the mileage, the remaining fuel, oil life related info and tire pressure. But I'm pretty sure that additional info is sent, e.g.: battery battery levels.

As of now, the service still claims that this is not a known issue (which would have led to different issues, e.g. people suing the dealerships and claiming damages for known product faults)

What I'm suspecting is that the car does at least one of the following:

• powering up too many power hungry modules for telemetry, when it isn't actually required, neither demanded explicitly by the car owner. The car could be tasked to send too much information to Ford's servers.
• recurrently powering up required modules (e.g. to read tire pressure) through extremely power inefficient electronics.

And I also believe that Ford could fix that by analyzing the power waste, checking which modules are turned on by mistake, and adjusting the software to no longer activate them. And the badly engineered - and extremely inefficient - ones probably need to be redesigned.

On 10/1/2025 at 2:53 PM, EmilC said:

Hi all,

I know this is an old topic, covering countless Ford models (including Fiesta, Kuga, who knows how many others). I noticed that the most common approach on the battery drain issue seems to be the "replace the battery with one made by Yuasa and change the SOC target". 
However, I have some additional information that I've never seen discussed before, and I think it worth being shared.

I own a 2024 Active X mHEV, which is affected by the "12V Battery low" issue since the first month. In my case. I won't dive into the relation with the service/dealer etc, it is irrelevant, they operated by he book provided by the mother company and, obviously, nothing wrong was found, for a few months. However, when the car reached the age of about 9 months, one of their battery tests indicated that the original 12 battery needs to be replaced. I want to underline this, that the battery reached an "no longer usable" rating from a certified Ford service unit after 9 months of ownership. Let's label this piece of information as A.

I've also learned about the glove box button issue (which doesn't break the contact every time), it was affecting me as well, but this is a small issue, because the glove box light power is cut after a few minutes after locking the car. This light doesn't stay lit for sufficient time to discharge the battery. 

The attempt to identify the root cause

I spend some time building a least-intrusive voltage logger solution, to find out what is happening, using a quite short sampling interval (1-5 seconds), which I've kept connected to the battery for extended periods of time, powered by an alternate battery. I wasn't able to make an accurate current logger, this would have become too intrusive, which I've avoided, therefore I've only relied on voltage information.

Taking the voltage into account, and the chart provided by @unofix, this logger provided interesting information, like a drop in voltage recurring once every hour when the car was parked, with the duration of 6 minutes on every occurrence. By doing some math, I ended up with the conclusion that the voltage drop can only be created by an electrical load of about 10 amps, and the drop was recurring with sufficient precision to consider this something which a) it is very likely controlled by software and b) operating on schedule, as programmed.

When does this thing stop? This recurring pattern ends when the battery reaches the "12V battery low" state, as a measure of protection. Again , this makes me think that what happens there is controlled entirely via software. It worth noting that there are exceptions from the pattern, in certain cases there is no recurring voltage drop every hour. I have no idea why. But, as a rule of thumb, the recurring voltage drop occurs more than half of the total time when the car is parked. The effect of this programmed activity is that the battery loses about 50% of its charge in less than two days. Let's label this piece of information as B. 

I wasn't able to find any link between this and other software/remote related settings. Turning remote start on and off didn't change anything, I also made an attempt to disable communications entirely, that didn't help as well. However, I have an active subscription for FordSecure (let's call this piece of info C)and real time maps, I believe these services are blocking the complete deactivation of all remote services.

Putting the things together

What matters here is that, from info A and B we can understand

• why the original batteries die very quickly - e.g. less than a year, instead of 4+. The programmed load wipes out discharge cycles out of the battery at a much higher rate, thus making the battery reach it's charge/discharge cycle count much faster. The problem doesn't seem to be caused by the accumulators, as much as it could be caused by excessive discharge, because of inefficient programming. 
• that replacing the battery with a larger one and setting the target SOC at a higher value doesn't solve the issue, it only makes it less visible. 

I suspect that FordSecure (C) could be the culprit, I work with software, and I think that it is very likely that a function like FordSecure reporting could be related to a recurring task running on the car.  I also know that the car is calling back home, as part of the 'Remote Features', and it does more things than we can see on the app dashboard. For example, I'm only able to see the mileage, the remaining fuel, oil life related info and tire pressure. But I'm pretty sure that additional info is sent, e.g.: battery battery levels.

As of now, the service still claims that this is not a known issue (which would have led to different issues, e.g. people suing the dealerships and claiming damages for known product faults)

What I'm suspecting is that the car does at least one of the following:

• powering up too many power hungry modules for telemetry, when it isn't actually required, neither demanded explicitly by the car owner. The car could be tasked to send too much information to Ford's servers.
• recurrently powering up required modules (e.g. to read tire pressure) through extremely power inefficient electronics.

And I also believe that Ford could fix that by analyzing the power waste, checking which modules are turned on by mistake, and adjusting the software to no longer activate them. And the badly engineered - and extremely inefficient - ones probably need to be redesigned.

Really interesting read, I've also got Ford Secure but only just noticed that it's being decommissioned December 2025.

 

So I wonder if after then we might see a change in battery drain. 

 

I've bitten the bullet and getting a Yuasa YBX7096 fitted hopefully soon. 

There seems to be quite a big difference between the MK4 and MK4.5 when it comes to this battery drain. My mk4 behaves perfectly since I replaced the battery. No crazy drain, and deep sleep occurring only after being parked for two weeks, or when unlocking and opening doors for a few days in a row, which is normal since the ECUs are awake for longer times.

Concerning the wakeup times, nowadays all cars have that implemented to run system monitoring tests. This is supported by your findings where you saw there is an increase in current drain every hour or so. My car wakes up to run a brake system test (probably tests other things as well, but I can hear the clicking in the brake module so I know this runs) four or five times, at different intervals, and after that it stops doing that. 

It looks like whatever Ford implemented in mk4.5 is buggy since it doesn't stop until the battery saving comes in. My guess is that they already know what it is and they are trying to solve it without admitting to their customers they screwed up :D.  

On 10/2/2025 at 5:26 PM, theroninhunter said:

I've also got Ford Secure but only just noticed that it's being decommissioned December 2025.

So I wonder if after then we might see a change in battery drain. 

I'll be able to tell after about two weeks, when my subscription will expire and it won't be renewed anytime before sorting out if it is connected to the drainage or not.

47 minutes ago, EmilC said:

I'll be able to tell after about two weeks, when my subscription will expire and it won't be renewed anytime before sorting out if it is connected to the drainage or not.

I don't think you'll be able to renew, it'll be  decommissioned this December........

Looks like theroninhunter has done a runner, or their battery has gone flat 🤣

On 10/1/2025 at 2:53 PM, EmilC said:

Hi all,

I know this is an old topic, covering countless Ford models (including Fiesta, Kuga, who knows how many others). I noticed that the most common approach on the battery drain issue seems to be the "replace the battery with one made by Yuasa and change the SOC target". 
However, I have some additional information that I've never seen discussed before, and I think it worth being shared.

I own a 2024 Active X mHEV, which is affected by the "12V Battery low" issue since the first month. In my case. I won't dive into the relation with the service/dealer etc, it is irrelevant, they operated by he book provided by the mother company and, obviously, nothing wrong was found, for a few months. However, when the car reached the age of about 9 months, one of their battery tests indicated that the original 12 battery needs to be replaced. I want to underline this, that the battery reached an "no longer usable" rating from a certified Ford service unit after 9 months of ownership. Let's label this piece of information as A.

I've also learned about the glove box button issue (which doesn't break the contact every time), it was affecting me as well, but this is a small issue, because the glove box light power is cut after a few minutes after locking the car. This light doesn't stay lit for sufficient time to discharge the battery. 

The attempt to identify the root cause

I spend some time building a least-intrusive voltage logger solution, to find out what is happening, using a quite short sampling interval (1-5 seconds), which I've kept connected to the battery for extended periods of time, powered by an alternate battery. I wasn't able to make an accurate current logger, this would have become too intrusive, which I've avoided, therefore I've only relied on voltage information.

Taking the voltage into account, and the chart provided by @unofix, this logger provided interesting information, like a drop in voltage recurring once every hour when the car was parked, with the duration of 6 minutes on every occurrence. By doing some math, I ended up with the conclusion that the voltage drop can only be created by an electrical load of about 10 amps, and the drop was recurring with sufficient precision to consider this something which a) it is very likely controlled by software and b) operating on schedule, as programmed.

When does this thing stop? This recurring pattern ends when the battery reaches the "12V battery low" state, as a measure of protection. Again , this makes me think that what happens there is controlled entirely via software. It worth noting that there are exceptions from the pattern, in certain cases there is no recurring voltage drop every hour. I have no idea why. But, as a rule of thumb, the recurring voltage drop occurs more than half of the total time when the car is parked. The effect of this programmed activity is that the battery loses about 50% of its charge in less than two days. Let's label this piece of information as B. 

I wasn't able to find any link between this and other software/remote related settings. Turning remote start on and off didn't change anything, I also made an attempt to disable communications entirely, that didn't help as well. However, I have an active subscription for FordSecure (let's call this piece of info C)and real time maps, I believe these services are blocking the complete deactivation of all remote services.

Putting the things together

What matters here is that, from info A and B we can understand

• why the original batteries die very quickly - e.g. less than a year, instead of 4+. The programmed load wipes out discharge cycles out of the battery at a much higher rate, thus making the battery reach it's charge/discharge cycle count much faster. The problem doesn't seem to be caused by the accumulators, as much as it could be caused by excessive discharge, because of inefficient programming. 
• that replacing the battery with a larger one and setting the target SOC at a higher value doesn't solve the issue, it only makes it less visible. 

I suspect that FordSecure (C) could be the culprit, I work with software, and I think that it is very likely that a function like FordSecure reporting could be related to a recurring task running on the car.  I also know that the car is calling back home, as part of the 'Remote Features', and it does more things than we can see on the app dashboard. For example, I'm only able to see the mileage, the remaining fuel, oil life related info and tire pressure. But I'm pretty sure that additional info is sent, e.g.: battery battery levels.

As of now, the service still claims that this is not a known issue (which would have led to different issues, e.g. people suing the dealerships and claiming damages for known product faults)

What I'm suspecting is that the car does at least one of the following:

• powering up too many power hungry modules for telemetry, when it isn't actually required, neither demanded explicitly by the car owner. The car could be tasked to send too much information to Ford's servers.
• recurrently powering up required modules (e.g. to read tire pressure) through extremely power inefficient electronics.

And I also believe that Ford could fix that by analyzing the power waste, checking which modules are turned on by mistake, and adjusting the software to no longer activate them. And the badly engineered - and extremely inefficient - ones probably need to be redesigned.

Thank you so much for this detailed write up, I also agree that it's Ford Secure as the likely culprit to this battery drain issue. Based on your assumption I've cancelled my Ford Secure subscription 5 days ago and do far (touching wood) I've not had a single issue of Low SOC error in the console or cabin lights not working on door opening. 

I naturally asked the rep who cancelled my subscription in the Ford CRC about if there is a known link with Ford Secure and the MK4.5 battery drain and obviously they denied it.