My ford focus has been in power save mode for a while but always started. Today the door wouldn’t open on remote.

managed to open drivers door with fob manual key.  No power in car so couldn’t start. 
 

plugged battery in and it was showing 5.5v !!

could the lack of use plus freezing weather have discharged the battery?

1 hour ago, Andyr55 said:

could the lack of use plus freezing weather have discharged the battery?

It certainly won't have helped, particularly as it sounds as if it was in a pretty low state of charge anyway.

Plenty of threads on this. Over the last few years I've simply accepted that, with my fairly irregular pattern of use, the "intelligent" charging system in this and my previous Fiesta will just not maintain a sufficient state of charge and give mine a regular top up.

I did it the other day before the cold spell hit and was rewarded with a first touch of the button start early yesterday, though the car was thoroughly iced over.

Once the outside temperature goes down, battery replacements go up 👍

This happened to me once in summer last year , battery dropped down to 4.5 volts. Went on this club site and I was given the explanation that it can happen when one of the modules fails to shut down draining your battery overnight, it has not happened since. My battery is now five years old and behaving impeccably , stop/start working better than it was three  years ago (fingers crossed).

18 hours ago, Andyr55 said:

Today the door wouldn’t open on remote.

managed to open drivers door with fob manual key.  No power in car so couldn’t start. 
 

plugged battery in and it was showing 5.5v !!

I doubt if your battery will ever make a full recovery now. Once the State Of Charge (SOC) drops below 10.50Volt then the battery capacity is usually permanently reduced.

You can try charging it while still connected to the car, make sure the negative battery charger lead is connected to the chassis earth point and not the battery. Charge for a minimum of 24 hours even if the battery charger is showing it's charged sooner.

1 hour ago, unofix said:

I doubt if your battery will ever make a full recovery now.

Some brands of charger - Ctek and Noco to mention two (don't know about Maypole) - claim that "recond" or "repair" mode respectively will recover a totally discharged battery. Worth a try I suppose if Andrew has access to one.

Never needed to try it myself, so can't comment from experience.

5 hours ago, Phil3747 said:

Once the outside temperature goes down, battery replacements go up 👍

Exactly this.  The cold weather will kill a struggling battery.

Whether you can recover it or not I doubt it will ever be the same.  A replacement is possibly going to be less hassle.  Ironic these climate control measures mean that some of us have to drive our vehicles more regularly to stop the batteries breaking!

7 hours ago, Eric Bloodaxe said:

Some brands of charger - Ctek and Noco to mention two (don't know about Maypole) - claim that "recond" or "repair" mode respectively will recover a totally discharged battery. Worth a try I suppose if Andrew has access to one.

Never needed to try it myself, so can't comment from experience.

It can get them back to a usable state but it can’t repair the damage. Some chargers refuse to charge a battery below a certain voltage. 

1 hour ago, alexp999 said:

It can get them back to a usable state but it can’t repair the damage. Some chargers refuse to charge a battery below a certain voltage. 

Yes, both the manufacturers I mention have an "analysis" function to indicate if the battery is capable of holding charge or not. I was suggesting this mainly as a way to just get the car going if a charger was handy, but it does sound a bit far gone for a long term fix!

The battery in my Mk4 dropped to 2.4v iirc.  (CBA to find the thread)  Maypole wouldn't charge it from that low.  BUT, I used a GB40 jump starter on it, fired up instantly and then charged back up surprisingly quickly just at idle.  Never had another issue with it.  I'm fairly certain it was caused by a module staying awake - either from downloading over wifi, or (ironically) from the previous time that I'd charged the battery without then running the engine.  I've got a feeling that may have confused a module and prevented it shutting down when locked.

I've been waiting to see that car appear on here, as I'd be interested to know whether the battery did eventually fail or not... 🤔

45 minutes ago, TomsFocus said:

I've been waiting to see that car appear on here, as I'd be interested to know whether the battery did eventually fail or not...

Well, that's another solution - get the car going and move it on PDQ!😀

20 minutes ago, Eric Bloodaxe said:

Well, that's another solution - get the car going and move it on PDQ!😀

Have batteries become that expensive 🤣

1 minute ago, tarbyonline said:

Have batteries become that expensive 🤣

I was thinking of if one of the "recovery" methods worked temporarily - but the price of stuff nowadays........😀

23 hours ago, TomsFocus said:

The battery in my Mk4 dropped to 2.4v iirc.  (CBA to find the thread)  Maypole wouldn't charge it from that low.  BUT, I used a GB40 jump starter on it, fired up instantly and then charged back up surprisingly quickly just at idle.  Never had another issue with it.  I'm fairly certain it was caused by a module staying awake - either from downloading over wifi, or (ironically) from the previous time that I'd charged the battery without then running the engine.  I've got a feeling that may have confused a module and prevented it shutting down when locked.

I've been waiting to see that car appear on here, as I'd be interested to know whether the battery did eventually fail or not... 🤔

Just what I did with the help of a knowledgeable neighbour!

ran car in drive for 15 mins and all seems ok.

just plugged my Maypole in and it showed 12.5v at start. 

Car was in battery saver mode but as I was planning a motor way journey 70 miles round trip I didn’t use my maypole. However just arrived home after trip and car is straight in saver mode. 
 

any suggestions? Could my issue when battery dropped to 5v have caused some issue ? 
 

I wonder if there is a reset function? 

5 minutes ago, Andyr55 said:

Car was in battery saver mode but as I was planning a motor way journey 70 miles round trip I didn’t use my maypole. However just arrived home after trip and car is straight in saver mode. 
 

any suggestions? Could my issue when battery dropped to 5v have caused some issue ? 
 

I wonder if there is a reset function? 

Put the Maypole on it overnight if possible.  It'll never get fully recharged by driving.

I wouldn't recommend resetting the BMS in this situation.  Only if you fit a new battery.

31 minutes ago, Andyr55 said:

Could my issue when battery dropped to 5v have caused some issue ? 

Once a car battery is discharged below 10V then you are extremely unlikely to ever get 100% of it's capacity back. Also the more often the battery suffers deep discharge the worse it gets each time.

10 minutes ago, unofix said:

Once a car battery is discharged below 10V then you are extremely unlikely to ever get 100% of it's capacity back. Also the more often the battery suffers deep discharge the worse it gets each time.

This.  

Tbh I’d have got a new battery straight away.  You’ll never be able to trust it unfortunately, its just too far gone.

18 hours ago, tarbyonline said:

This.  

Tbh I’d have got a new battery straight away.  You’ll never be able to trust it unfortunately, its just too far gone.

Even though my present battery is only 2/3 years old? 
 

battery fully charged with maypole but still in battery saver mode! 
 

any suggestions?

3 minutes ago, Andyr55 said:

Even though my present battery is only 2/3 years old? 
 

battery fully charged with maypole but still in battery saver mode! 
 

any suggestions?

If it's been down to 5.5V it's probably taken at least a year off its life.

The batteries Ford fit are weak from factory, especially if you have the 60Ah one.

What voltage do you get from the battery at rest?

Sorry don’t have battery tester. 

Have you driven it yet?  May take a couple of key cycles for battery saver to stop even if the battery is good.

People seem to like replacing batteries on here.  I prefer to squeeze as much as possible out of them.

If voltage drops considerably overnight after being fully recharged then it'll need to be replaced.  You will need a volt tester though.  Maybe ask that neighbour again lol.

Tom, not had chance to drive yet but will be this week! 
 

question. When I attach my Maypole to the battery is the voltage showing the actual battery voltage? 

1 hour ago, Andyr55 said:

Maypole to the battery is the voltage showing the actual battery voltage? 

No.

You need a digital multimeter, something like this will do: https://www.screwfix.com/p/lap-ac-dc-digital-multimeter-600v/75337

 

1 hour ago, Andyr55 said:

Tom, not had chance to drive yet but will be this week! 
 

question. When I attach my Maypole to the battery is the voltage showing the actual battery voltage? 

Hmm.  Not to disagree with Unofix, but I would say that yes, at the very first point you attach the Maypole, it does show battery voltage.

After that it's not reliable as it shows the voltage that it's putting into the battery rather than what the battery will hold at rest.