Hi everyone…

I know there’s loads of topics on this but I’m asking for tailored advice rather than reopening or taking an existing thread off topic.

I’ve recently purchased a Focus 2022 (registered December 2022) MK4.5 MHEV 155bhp from an MG dealer. No idea where they acquired it from though

I connected it up to the Ford Pass app and within the first 24 hours it would tell me it’s gone in to low power mode. That lead me to this forum and I’ve read a multitude of posts around battery drain issues over the last couple of months

On entering this mode I’ve immediately connected my multimeter and it shows 11.9V

The car then shows a whole range of issues such as steering lock failure, spanner and various warning lights which ALL clear once turned on so have put it all down to the battery dying. Bizarrely my interior lights have always worked when I receive this message along with keyless entry, puddle lights etc. There is also no light in the glovebox which I will pull out and see whether it’s unplugged, bulb removed or bulb blown.

The car is driven 5 days a week and gets a minimum of 2 hours each day so I would assume that’s plenty of time to charge the battery?

The car drives fine, the only issue I’ve noticed is occasionally the start stop will not work and rather than being green, it will beep at me, show some error message and illuminate orange with a line through it. Usually happens a few times a day but there’s no pattern to it

I was passing Kwik Fit the other day and had a check done. I can’t upload the picture of the print out as there’s a limit size of 2mb so I will copy the writing instead

VOLTAGE:	11.56 V
RATED:	EN 760 A
MEASURED:	EN 470 A
IR:	5.55 ml

TEMPERATURE:

86.0 °F/ 30 °C

STATE OF CHARGE (SOC):

0 %

STATE OF HEALTH (SOH):

61 %

They have told me the battery is healthy and it just needs a recharge and to drive it more than 5 minutes a day. I said it gets driven 2 hours a day 5 days a week, so the guy laughed and said well drive it more then!

I came back to this forum and found the Maypole smart charger suggestion. Purchased one off Amazon for £23, plugged it in and it showed 10v but bizarrely went green after exactly 45 minutes and sat at 13.1v. I left it on overnight anyway as others had suggested so it did eventually have around 10 hours plugged in

I’d like to get a second opinion on the battery as should it be showing 11.56v immediately after turning the car off? More so the measured 470A rather than 760A written above? And the SOH being 61%?

Would it really chew through the battery in 3 years? It would appear it has the original Varta battery installed

Thanks in advance!

Just buy a new, non Ford battery, preferably of a higher capacity as the one already fitted.

Get yourself set up on FORScan and reset the charge level to 95% and it'll be OK, you'll never have another issue

Ford's batteries are cheap junk (cost)

At just about the limit on Ah that that system can cope with (cost)

And the BMS never lets the car charge more than 80% no matter how long you drive it for

My advice will fix it forever

7 hours ago, sm007 said:

The car drives fine, the only issue I’ve noticed is occasionally the start stop will not work

BTW the start/stop on an MHEV utilises the ISG and 48v battery, not the 12v.

https://www.ford.co.uk/support/how-tos/electric-vehicles/hybrid-hybrid-plug-in/how-does-a-mild-hybrid-electric-engine-work

it really does make little difference how far and for how long you drive it, unless the pattern of use suits the system parameters.

Counter intuitively I've often found a mix of shorter journeys, with lots of braking, overrun etc will keep the battery charged better than the traditional "take it for a trip to the coast" advice.

i've found a full session on a smart charger takes it up to around 13.2v, but within a few days its back around 12.4v (80% SOC) as Dave has already mentioned.

You've probably seen this chart before!

I had exactly the same problem, 2022 focus. 11.56v is no good, change the battery. I had this issue about 12 months ago with low power (battery) warnings showing on the app and on one particularly cold morning the infotainment screen failed to come on. I had no others warnings showing though. Ford replaced the battery and battery tray under warranty as the original battery was leaking. It's been OK since. I do think the battery is too small for the car though, especially with the stop/start

3 hours ago, Eric Bloodaxe said:

it really does make little difference how far and for how long you drive it, unless the pattern of use suits the system parameters.

That seems to be the critical issue with the more recent models. From what's been said elsewhere on this forum it appears the system is now set up so the alternator only charges the battery when the engine is not under load. So if you're mainly cruising at 50, 60, 70 it may not be charging at all and only kicks in when you decelerate or are running slowly under low throttle openings. Increasing the maximum SOC setting to 95% and fitting a bigger battery as suggested by @DaveT70 is definitely worth doing and will undoubtedy help but if your driving pattern isn't putting back what's being taken out it will ultimately only lengthen the time between putting it on a charger.

Thanks for the replies…

I’ve seen many people suggesting the Yuasa YBX7096 battery. I do not own a laptop so would be stuffed with the Forscan options

I’ve also seen another member on here purchasing the Yuasa YBX9096 battery and apparently the AGM battery running just fine?

Interesting the comment above regarding cruising. That is EXACTLY what I do with the cruise control

Thanks again for the replies and the help. What’s everyone’s views on the battery report in my initial post? My understanding from that is the battery has had it but I’m unsure why Kwik Fit is saying it’s a perfectly healthy battery? Would the battery really be done after 3 years?

Ive found the Yousa battery for £100 here -

https://www.batterycharged.co.uk/shop/brands/yuasa-batteries/yuasa-automotive-batteries/yuasa-ybx7000-efb-batteries/yuasa-ybx7096-12v-75ah-efb-start-stop-plus-battery-1508671.html?srsltid=AfmBOorgPZ4HWdFAJg6fpQBAuHuznE8ZbmeTntIPd8dl1QoMUqPP4L1z

1 hour ago, mjt said:

Increasing the maximum SOC setting to 95% and fitting a bigger battery as suggested by @DaveT70 is definitely worth doing and will undoubtedy help but if your driving pattern isn't putting back what's being taken out it will ultimately only lengthen the time between putting it on a charger.

@unofix made a similar point in this earlier thread (which also comment on AGM):

https://www.fordownersclub.com/forums/topic/158082-mk45-another-battery-compliant-lol/

(Seems to me it's a bit like all the pills we older members have to take - it won't cure the problem but (hopefully) it delays the inevitable!😀)

If the SOC is set to 95% you are not going to be going anywhere near 80%, that's the main issue.

The SOC being set to 85% is daft

12 hours ago, sm007 said:

What’s everyone’s views on the battery report in my initial post? My understanding from that is the battery has had it but I’m unsure why Kwik Fit is saying it’s a perfectly healthy battery? Would the battery really be done after 3 years?

They're only looking at battery health percentage and ignoring all of the actual information on the reader.

Yes that battery is knackered after 3 year, that's not far off average for a Mk4 Focus battery. But it is frustrating that they don't appear to last any longer on MHEVs, despite the MHEV battery managing stop start instead of the 12v battery.

You can buy a used windows laptop cheaply and even sell it on if you don't have space to store it. I've bought a few over the years specifically for vehicle software. If you do change to an AGM battery I would want to alter the charging type on Forscan. They do charge very differently. I swapped the EFB on my Golf for an AGM and notice a massive difference in the way it holds voltage and also the way it takes voltage from the Maypole charger.

Ended up buying the Yuasa 7096 and charged it up for 24 hours using the Maypole…

Fitted today but was a bit of a pain to install. It was made much easier by removing the air filter then the battery just slides straight in

I reset the BMS, it took about 20 seconds for the battery light to flash 3 times and all is good so far.

I put the multimeter on and running it was on 12.7v. Soon as I turned the lights on it jumped to 14.4v so is that the key to make the alternator come on? Before it would always be on with the old battery lights or no lights

I was pleasantly surprised and some what amazed it hasn’t lost any of the radio stations, or in fact any settings at all!

Next is to sort out FORscan, or find someone local who can do it for more haha

2 minutes ago, sm007 said:

Soon as I turned the lights on it jumped to 14.4v so is that the key to make the alternator come on? Before it would always be on with the old battery lights or no lights

If the battery SOC was above 80% with no auxiliary electral demand then it won't charge.

@TomsFocus hi, i want to change my default battery with this battery "Varta silver dynamic AGM A7 70ah 760A"

is possible?

in this moment i change my soc % and set it to 95%... with the new battery does it need to be changed? and whitch options does it need to be changed?

thanks!

1 hour ago, Riccardo99 said:

@TomsFocus hi, i want to change my default battery with this battery "Varta silver dynamic AGM A7 70ah 760A"

is possible?

in this moment i change my soc % and set it to 95%... with the new battery does it need to be changed? and whitch options does it need to be changed?

thanks!

I don't know unfortunately. On my Golf I changed the setting from EFB to fleece (AGM) using VCDS.

I was hoping Forscan had the same setting, but since posting that I have read that Forscan doesn't have that option on a Mk4.

As you have some experience with Forscan already, I would just recommend looking through the settings to see if there's one for AGM.

Check this post and forum thread for discussion on installing AGM batteries in the Focus

20 hours ago, Riccardo99 said:

@TomsFocus hi, i want to change my default battery with this battery "Varta silver dynamic AGM A7 70ah 760A"

is possible?

in this moment i change my soc % and set it to 95%... with the new battery does it need to be changed? and whitch options does it need to be changed?

thanks!

If you @Riccardo99 make this change (to AGM) I'd interested to hear how it goes. My Focus is of similar vintage (2023) and I suspect there will be need to change the battery if I keep the Focus through next winter. Personally, having already changed the target SOC to 95%, and having seen the benefits, I wouldn't choose to roll back to the absurdly low 80%.

Just an update…

Since installing the battery a week ago it’s solved all the problems, no more notifications from the app and no strange messages on the screen

As a side note, if anyone is local to me (or nearby so I can reach them), I’m prepared to sort someone out to change the battery to 95% in FORScan