Mk4 negative for charging

[Wino]

11 hours ago, Tizer said:

That is interesting. I wonder if it would charge more if you changed it to whatever size you have. 

The one fitted to my car is a 60/600.  If your one is a 70 then 56 is 80% of it as you probably already know. I don't have an extended licence at the moment so I can't check what mine has been factory set to.

That's what I was thinking as the battery on the car is a 70 so not sure why Forscan is suggesting it's a 52.

[Tizer]

22 minutes ago, Wino said:

That's what I was thinking as the battery on the car is a 70 so not sure why Forscan is suggesting it's a 52.

It would be interesting to see if other people with petrol manual cars and the 60 Ah batteries have their ones set to 48.

[Buxty]

41 minutes ago, Tizer said:

It would be interesting to see if other people with petrol manual cars and the 60 Ah batteries have their ones set to 48.

2019 Vignale 182ps petrol manual, just checked mine, showing in BCM as 43Ah! 

edit for clarity: it’s also a 60Ah original from factory fitted. 

[Tizer]

1 minute ago, Buxty said:

2019 Vignale 182ps petrol manual, just checked mine, showing in BCM as 43Ah! 

That is worse than I thought, nearly 30% less. I wonder if changing it to the correct size would make it charge quicker or not, who knows.

[Wino]

5 minutes ago, Buxty said:

2019 Vignale 182ps petrol manual, just checked mine, showing in BCM as 43Ah! 

edit for clarity: it’s also a 60Ah original from factory fitted. 

So why is it showing a 43ah battery when you have a 60ah fitted ? 

Has it been configured incorrectly when the car war was originally built ? 

[StephenFord]

This thread is a real eye opener! How to charge the battery on a nearly new ca??. Something I do every couple of months on mine, BUT it's 16 years old. Mehhh... you can keep 'new' cars, seem more trouble than they're worth 🤣

[colinmcg71]

Same here for me. 2.3 EcoBoost, 60Ah under the bonnet, FORScan reports 43Ah. 🤨

 

[Wino]

2 minutes ago, colinmcg71 said:

Same here for me. 2.3 EcoBoost, 60Ah under the bonnet, FORScan reports 43Ah. 🤨

 

So it seems a widespread scenario. Thinking of changing ours to what the battery actually is and re setting the BMS afterwards and see if theres any improvement. 

[Buxty]

So, my last message was while sitting for a Halfords to open, he used his Yuasa branded battery tester and it showed 582A charge out of 600A. So it would seem the car is charging fully…annoying how the S/S didn’t get the memo though! 😝

[colinmcg71]

13 minutes ago, Buxty said:

So, my last message was while sitting for a Halfords to open, he used his Yuasa branded battery tester and it showed 582A charge out of 600A. So it would seem the car is charging fully…annoying how the S/S didn’t get the memo though! 😝

That's good to know. At least it's fully charging. 👍

[unofix]

It seems on the face of it that someones software is wrong, and possibly the root cause of many batteries not getting the correct charge.

As I see it, the problem is either Ford have an issue and are 'double' compensating with the charge settings by reducing the real battery size form what ever it actually is and putting a figure of approximately 80% in to the software and then also doing the same again by setting the SOC to 80% when I would have expected it to be only one or the other but not both.  If my understanding of what Ford have done is correct (and I might be totally wrong) then a car fitted with a 70Ah battery would have this set as a battery size of 56Ah. Then with the SOC set to 80% (the normal default for UK vehicles) then that would further reduce it to only 44.8Ah.

The other alternative could be a bit of a software glitch with FORScan. Perhaps FORScan is reading the correct battery size, for example 70Ah and then because the SOC is set at 80% it displays the battery size as 56Ah. This theory can easily be tested by using FORScan to adjust the SOC to say 90% and then see if it reports the battery size as 63Ah.

 

[colinmcg71]

11 minutes ago, unofix said:

It seems on the face of it that someones software is wrong, and possibly the root cause of many batteries not getting the correct charge.

As I see it, the problem is either Ford have an issue and are 'double' compensating with the charge settings by reducing the real battery size form what ever it actually is and putting a figure of approximately 80% in to the software and then also doing the same again by setting the SOC to 80% when I would have expected it to be only one or the other but not both.  If my understanding of what Ford have done is correct (and I might be totally wrong) then a car fitted with a 70Ah battery would have this set as a battery size of 56Ah. Then with the SOC set to 80% (the normal default for UK vehicles) then that would further reduce it to only 44.8Ah.

The other alternative could be a bit of a software glitch with FORScan. Perhaps FORScan is reading the correct battery size, for example 70Ah and then because the SOC is set at 80% it displays the battery size as 56Ah. This theory can easily be tested by using FORScan to adjust the SOC to say 90% and then see if it reports the battery size as 63Ah.

 

I see in David’s @Wino post above he has his SOC set to 95% and FORScan still reports his 70Ah battery as 52Ah.

[unofix]

Hi @colinmcg71, yes good point. So that would seem to rule out FORScan as doing it's own calculations.

Maybe I'm calculating this totally wrong, please feel free to correct me.

70Ah - 25.7% = 52Ah

60Ah - 28.2% = 43Ah

[colinmcg71]

3 minutes ago, unofix said:

Hi @colinmcg71, yes good point. So that would seem to rule out FORScan as doing it's own calculations.

Maybe I'm calculating this totally wrong, please feel free to correct me.

70Ah - 25.7% = 52Ah

 

You’re bang on, 52Ah is 74.3% of 70Ah,

My 43Ah is 71.7% of 60Ah.

No idea why though 🤔

[Buxty]

Is a weird one, my SOC is set to 90% but I didn’t check to see what the Ah was set to before. 

[Jonro2009]

59 minutes ago, colinmcg71 said:

I see in David’s @Wino post above he has his SOC set to 95% and FORScan still reports his 70Ah battery as 52Ah.

I was just about to say that too. 

I know it's a different car but the Mk5 Mondeo always seems to have the correct battery type inputted in Forscan, I'm not sure what the SOC is set to though. It's confirmed on multiple vehicles as being correctly inputted as it's something we regularly discuss. 

[Tizer]

A cynical person might think that because Ford decided not to fit AGM Batteries or cooling ducts (the ducts might increase the emissions and not be compatible with the Active Grill Shutter), to cars that need them then they have gone out of their way to try to ensure that their Batteries last the warranty period without getting fried for anyone that does use their Start Stop.

[colinmcg71]

I've just started a new thread on the FORScan forum to see if we can shed any light on this.

 

[RMurphy195]

That sounds good Colin.

I've just set up an experiment to analyse the S/S behaviour in relation to the use of my CTEK charger, will publish results when I've assembled some data of the next few weeks (well, you've got to do something to fill your retirement time haven't you!)

I've also ordered the cable so I can get my Forscan readings. I won't actually change 'owt yet, partially because the car is under warranty still, and also because when I have the towbar fitted there will be a software update.

This software update will at minimum change the behaviour of the car's reversing sensors, reverse lights and rear fog light when a trailer is connected, run the caravan roadlights in tandem with the car, and will also cause the caravan battery to be charged and the fridge to run (somehow). So it will be interesting to see if anything changes without me actually doing 'owt!  This won't be for a few weeks though.

(I used to work in IT and can recognise not-well-though out processes when I see them ...)

[iantt]

Charging a battery fully will enable stop start if battery was low soc. But as soon as you drive off the alternator will not charge battery at all until battery discharges  back in the 68-80 soc range. So pretty pointless fully charging really. 

Because the way the charging/ discharging at the 68-80 range operates the battery sulphates up and then the battery gets a full charge to 100% with higher than normal charging voltage. All this increases the longevity of flooded/AGM batteries. Changing soc in forscan may or may not change the longevity of the battery. 

Just to add I'm no expert in the technicalities of exactly how or why. 

 

[unofix]

On 1/3/2022 at 2:20 PM, iantt said:

Changing soc in forscan may or may not change the longevity of the battery. 

Very True.

What I would say is given the number of people just on this forum who have had their battery replaced (sometimes more than once) in under 18 months, the current system of charging seems to have a fatal flaw !!

On 1/3/2022 at 2:20 PM, iantt said:

But as soon as you drive off the alternator will not charge battery at all until battery discharges  back in the 68-80 soc range.

Yes I think that is very probably the case. The only thing to do to improve the situation would be fully charge the battery, and change the SOC to 95%. Then as you say the alternator will let the battery charge fall back to 95% and then maintain it there.

[iantt]

I agree the current way the battery and charging system is operating is certainly not ideal. Emission regulations have brought about this less than ideal situation. I'm currently reading what little info I have about how and why. Charging voltage can be as low as 12.2vto 14.7-14.9v  . In refresh stage can be 15.2v. 

Charging ocours in decelaration . So driving style may affect the ability to keep charge at 80% 

[RMurphy195]

On 1/3/2022 at 2:44 PM, iantt said:

I agree the current way the battery and charging system is operating is certainly not ideal. Emission regulations have brought about this less than ideal situation. I'm currently reading what little info I have about how and why. Charging voltage can be as low as 12.2vto 14.7-14.9v  . In refresh stage can be 15.2v. 

Charging ocours in decelaration . So driving style may affect the ability to keep charge at 80% 

I wonder what deceleration means (specifically tht is, within the controlling software)? If, for example, it means noload on the engine that would be interesting at higher speeds where air resistance becomes a factor - even more so towing a caravan, where the air resistance effect is dramatically shown on the diesel by the halving of the mpg and the need to keep a heavy throttle opening - which in my book does not = declration, even downhill (notorway-style) sometimes!

[RMurphy195]

Well, a bit of an update a little earlier than I'd thought, following recharging the battery.

In summary (NB screen heater etc not used unless otherwise stated, drive mode "Normal"):

Day 0 - Fully charged battery, left the car overnight

Day 1 - Did a half-hour journey A roads, Outside Air Temp = 7 deg, SS worked even within 1/2 mile of home where engine was cold. Similar on return journey a couple of hours later, OAT now 8, SS worked when engine was cold and later when warmed-up.

Day 2 - Car not used

Day 3 - Set out on 2 1/2 hour, 40-odd mile journey, OAT 4 0 8 deg, SS worked during first 10 miles or so whether engine hot or cold. Disabled SS then re-enabled near destination - SS no longer working!!! Return journey SS still would not work, either when still daylight (lights off) or after dark (lights on).

Day 4 - Urban shopping 14 mile return trip, OAT 0 deg SS did not work at any time. By then had "discovered" the display which showed “Engine is on due to vehicle recharging”  when idling, “Engine on normal operation” when above idle. Screen heaters (front/rear) used for a short while before setting out

Day 4 (Again) - School run about 10-15 mins each way, urban OAT 3deg. Outward - still not working. Prior to return - tried the headlampflasher+brake pedal BMS reset. Display now shows something like "Engine on will stop at next vehicle stop" or somesuch, switched to "Engine on normal operation” once moving. And the SS worked!

This seems to confirm a theory that there is a discrepancy between what the charging system does when charging the battery, and the Battery Monitor threshold that the Stop/Start uses. I've now changed this threshold to make it lower - now fits the current state of charge of the battery? If so, I might find the problem re-occurring over the next few days! Or I might end upwith a flat battery ...

Plus an observation - Cold outside, engine also cold - the D**N thing isn't supposed to work under those conditions is it? Well, it did!!

 

 

[unofix]

Hello @RMurphy195 an interesting little study. I know somewhere you may have already given these details but can you just confirm these points please:

What Ah size battery is fitted ?

What Ah size battery is actually set in your vehicles software ?

What do you currently have the SOC set to ?