I’ve had my 2023 mk4.5 Focus ST for three weeks and am getting the well known “Remote features disabled to preserve battery” problem that has been widely discussed.

The usual advice seems to be:

1.      Use a trickle charger regularly

2.      Get a new battery

3.      Drive the car a lot more

4.      Change the SOC threshold from 80% to 95%

 

My issue with all of these is that they are treating the symptoms, not the cause.

 

The deep sleep seems to kick in when the car measures SOC to be about 47%.

Yesterday the car, which was parked, dropped from 52% to 47% in 10 hours.

So there is a permanent current draw of something like 350mA when parked.

It is this current draw that is the cause of the problems, not points 1-4 above.

 

I assume it is “features” like the remote monitoring of the car that is causing this.

 

Can anyone suggest how I could do some or all of the following?:

 

5.      Reduce current draw when parked by disabling as many features as possible. (eg with settings, Forscan or mods)

6.      Change deep sleep settings so that puddle lights and interior lights come on when the car is unlocked

7.      Increase deep sleep threshold from 48% to eg 65%

Even the alarm immobiliser causes draw.

The cause of the issue is poorly set BMS and cheap batteries with just enough capacity to cope

It's pointless keep charging your car as BMS will just let it drop to 80% again

Fit a new, fully charged, higher capacity battery than what is fitted. Whatever is on fit the next one up👍

Adjust BMS SOC level to 95% 

1 hour ago, DaveT70 said:

Even the alarm immobiliser causes draw.

The cause of the issue is poorly set BMS and cheap batteries with just enough capacity to cope

It's pointless keep charging your car as BMS will just let it drop to 80% again

Fit a new, fully charged, higher capacity battery than what is fitted. Whatever is on fit the next one up👍

Adjust BMS SOC level to 95% 

But all that does is buy a bit more time, it doesn't fix the problem.

The 350mA constant current draw when parked is probably being pulled by multiple circuits (regardless of battery capacity or SOC threshold), and I'm sure I would happy to live without some of the features whilst it's parked. It's those possibilities I want to explore.

For context this car is mainly a weekend drive only, not a daily use. The current Ford algorithm will have it sitting in deep sleep mode at 47% charge for the majority of time (in my circumstances). If I had full access to the BMS software I could fix this in no time at all, but I don't, and I don't believe Ford will be interested in improving this now the car is out of production. So I'm looking for workarounds to reduce stationary current draw.

If you want a permanent fix, then buy a car built before 2013.

There is no magic silver bullet going to fix a 2023 model. The best you can do is as Dave has said, fit a larger capacity battery and change the BMS to 95%%

2 hours ago, MarkPi said:

Yesterday the car, which was parked, dropped from 52% to 47% in 10 hours.

So there is a permanent current draw of something like 350mA when parked.

The battery SOC didn't really drop from 52% to 47% in 10 hours. The battery SOC was simply recalculated by the BMS based on the battery voltage and was set to 47% based on that voltage.

Sometimes you will see the SOC increase when the car is parked for the same reason.

Here's an example where the battery SOC reported by the car has magically jumped upwards from 86% to 93% while the car was parked:

 

34 minutes ago, unofix said:

If you want a permanent fix, then buy a car built before 2013.

There is no magic silver bullet going to fix a 2023 model. The best you can do is as Dave has said, fit a larger capacity battery and change the BMS to 95%%

In my circumstances I would see no benefit with a larger battery and changing BMS to 95%, it will still sit at 47% in deep sleep mode for most of the time. The (up to) one hundred miles driven over a weekend won't bring it above 80%, let alone 95%, and it will deplete again over the week.

If there are some features that can be turned off in Setting menu it might help a bit.

If there are other features that can be disabled or altered in Forscan it might help some more.

If there are bits of hardware that can be disabled by splicing a timed relay into a wiring loom it might help further.

31 minutes ago, pcaouolte said:

The battery SOC didn't really drop from 52% to 47% in 10 hours. The battery SOC was simply recalculated by the BMS based on the battery voltage and was set to 47% based on that voltage.

Sometimes you will see the SOC increase when the car is parked for the same reason.

I appreciate the SOC reading is not going to be particularly accurate, however I believe it is calculated by the BMS module integrating current (drawn or charged) over time, rather than simply looking at the voltage (which due to the internal resistance will vary hugely depending on load). This is why it's important to connect the negative lead of a charger to chassis ground rather than battery negative - it effectively counts the coulombs going in and out of the battery.

I'm definitely not taking the 350mA quiescent current draw as particularly accurate, however there must be several hundred mA continuous draw for the batteries to deplete so quickly. If I get time (ha) maybe I'll try to actually measure it in situ.

Older cars would typically draw 10s of mA when parked, not 100s. It's a modern problem, and just because Ford (and others) have dumped it on us doesn't mean that bright minds can't look to improve a bad situation.

14 minutes ago, MarkPi said:

it is calculated by the BMS module integrating current (drawn or charged) over time

Yes, that is true. But in addition to that, when the car is standing idle for a period of time (several hours) the BMS system then resets the SOC based on the battery voltage. This is what you are seeing. 

For information Ford quote a Current Draw of over 50mA after the car has been sitting for a period of time (I can't remember exactly how long, probably around an hour) without being woken up as unacceptable.

There will be a draw of 350mA or a lot more after switching off or waking up the car for a considerable time. 

15 hours ago, MarkPi said:

In my circumstances I would see no benefit with a larger battery and changing BMS to 95%, it will still sit at 47% in deep sleep mode for most of the time. The (up to) one hundred miles driven over a weekend won't bring it above 80%, let alone 95%, and it will deplete again over the week.

There is a benefit and it will work, believe me

My daughter only does about three miles a day and was having the same issue, plus she drives everywhere with the heated steering wheel and seat on

Fitted a much higher capacity battery, can't remember from what to what (it was Diesel plus) and reset BMS to 95% and she's gone two years now with no issues

I feel your pain @MarkPi, having been struggling with this issue since buying my ‘73 plate Focus earlier this year. Following advice on these forums I’ve opted for both

Quote

1.  Use a trickle charger regularly, &  4.  Change the SOC threshold from 80% to 95%

These have definitely helped, and battery saver mode occurrences were significantly reduced, especially during the spring & summer months.  Now in the dark winter months I find myself plugging in the trickle charger on a much more regular basis. I probably should upgrade the battery but (i) I am not sure how much longer I will keep my Focus, and (ii) as I religiously garage my car when not in use, which is a lot of the time, it’s not too big a deal for me to leave it on charge.
-

Quote

6.      Change deep sleep settings so that puddle lights and interior lights come on when the car is unlocked

Personally, it’s this (6) that I find most irritating, in the dark winter months, and if there was a simple Forscan tweak that could detach the loss of lightning then I might find the battery saver mode activations more tolerable.

 

General advice for owners of all Focus Mk4 (all petrol and diesel models), to help improve the reliability of the battery and it's State of Charge:

Fit yourself the Yuasa YBX7096 battery, increase the State Of Charge to 95% and live happy ever after 🎉

52 minutes ago, unofix said:

General advice for owners of all Focus Mk4 (all petrol and diesel models), to help improve the reliability of the battery and it's State of Charge:

Fit yourself the Yuasa YBX7096 battery, increase the State Of Charge to 95% and live happy ever after 🎉

I might give that a try anyway as it can only help. But although it might prolong the time before the problems start again, it doesn't actually fix the root cause.

If I had a leak in a plumbing system I would want to stop the leak, as opposed to pouring more water in at the top or fitting a bigger storage tank.

There's probably dozens of "leaks" in the whilst-parked electronics, and if I can plug a few of them up it would certainly help.

1 hour ago, unofix said:

General advice for owners of all Focus Mk4 (all petrol and diesel models), to help improve the reliability of the battery and it's State of Charge:

Fit yourself the Yuasa YBX7096 battery, increase the State Of Charge to 95% and live happy ever after 🎉

BTW does an 096 battery fit in MK4.5 ST?

I thought they took 100 batteries?

2 hours ago, MarkPi said:

it doesn't actually fix the root cause.

The "Root Cause" is the European Union, and yes we did leave, but it is still affecting us now and will do for at least the next 20 years.

The EU, set impossible emission targets forcing motor manufactures to adopt crazy charging algorithms, using the alternator to only charge the battery on engine over run. It is the EU that insists on all of the extra 'Safety' equipment including the telemetry unit (modem) that tracks the cars moment at all times. It is the EU that has forced the fitting of the 'SOS' call system which is live all of the time. Lastly perhaps not the EU, but the insurance companies who insist on the alarm system and PAT security.

If the car is left undisturbed for an hour or more the quiescent current draw on the battery will fall to around 80mA. It is very difficult to actually get to measure that current, since even just walking near the vehicle with the keyfob in your pocket is enough to cause the vehicle to begin waking up in readiness for you to open the doors and start the engine. 

2 hours ago, MarkPi said:

BTW does an 096 battery fit in MK4.5 ST?

I thought they took 100 batteries?

To be honest I've never tried fitting the Yuasa YBX7096 in to a Focus Mk4.5

The Focus Mk4.5 is normally fitted with the '100' battery so that would have to be the Yuasa YBX7100 which is only 650A 65Ah as apposed to the YBX7096 which is 700A 75Ah

It will depend if you can fit a battery that is 15mm taller in to the battery tray on the Mk4.5

21 hours ago, MarkPi said:

BTW does an 096 battery fit in MK4.5 ST?

I thought they took 100 batteries?

It’s a valid question. If you drill into these forums it appears that the Yuasa YBX7096 has been used by several members with a MK. 4.5 Focus.  Although few ever seem to update threads with confirmation that they did fit; but then they undoubtedly would if it didn’t!?   Reviews on the Tanya web site  also support the view that 7096 works well as a replacement for the 4.5 Focus (and there was one owner with Ford Focus ST 2.3 Petrol 2023).  Probably worth checking whether the ST has a different sized battery box to ‘standard’ 1.0 ecoboost models.