The dreaded Increased battery discharge warning

Nanu · Post by **Nanu** » Tue Jun 02, 2020 8:35 pm

I know this has been the subject of several posts but I have never understood fully what this problem is and how to cure it. Can someone in very laymans terms explain how I can travel 3 miles to my local supermarket with no warning then on my return the warning is there. Sometimes I can go a week without using the car and no warning then for no reason the next day it appears. sometimes I have to reset it and sometimes it just goes away withou having to do anything. The car is 5 years old so it shouldn't be the battery but would a battery charger help?

Smartbear · Post by **Smartbear** » Tue Jun 02, 2020 8:57 pm

Nanu wrote: ↑Tue Jun 02, 2020 8:35 pm I know this has been the subject of several posts but I have never understood fully what this problem is and how to cure it. Can someone in very laymans terms explain how I can travel 3 miles to my local supermarket with no warning then on my return the warning is there. Sometimes I can go a week without using the car and no warning then for no reason the next day it appears. sometimes I have to reset it and sometimes it just goes away withou having to do anything. The car is 5 years old so it shouldn't be the battery but would a battery charger help?

It does sound like the battery, they can be weakened at that age especially if it’s been allowed to flatten previously.
Charging just masks the problem of a battery not holding its charge very well

Rob

Nictrix · Post by **Nictrix** » Tue Jun 02, 2020 9:05 pm

A few years ago I got this every now and again in the X6.
It didnt really make sense as sometimes the warning would show up after a minute of the ignition being off and other times it could be 10 minutes or more.
Long story short, one day the car wouldnt start as the battery was dead with no other warning. The car was parked in front of the garage with our other car in it and with the auto gearbox and electric handbrake it couldnt be moved.
I would replace the battery before you get stuck.

Maybach_man · Post by **Maybach_man** » Wed Jun 03, 2020 5:02 am

Look for parasitic drain on the car...and get a larger capacity battery installed when you change it...BMW battery's arnt all that only 2 year warranty...

tintoverano · Post by **tintoverano** » Wed Jun 03, 2020 6:12 am

these batteries last, mine served 9 years - when they start going out, one of the first signs is the increased discharge alert

Jollyjoiner · Post by **Jollyjoiner** » Wed Jun 03, 2020 8:01 am

Don't forget that these cars have regenerative charging systems so the alternator will only cut in and start to charge whilst the engine is slowing down i.e when you are braking. So, if your short journey is mainly all on the throttle then the battery will not get much charge.

Pbondar · Post by **Pbondar** » Wed Jun 03, 2020 8:54 am

These prolonged periods of inactivity plus short drives doesn’t do these systems any good...

I’ve had to charge my E88 twice this year due to inactivity...

My Volvo XC70, similar age and limited use has had similar issues..

Normally after 6-10 miles it tell me that auto stop/start is available...for the last 3 months due to very limited use and a charge it’s never become available ...

So it’s a mixture of battery age/lack of use / limited mileage ..IMHO..

tintoverano · Post by **tintoverano** » Wed Jun 03, 2020 8:57 am

Pbondar wrote: ↑Wed Jun 03, 2020 8:54 am So it’s a mixture of battery age/lack of use / limited mileage ..IMHO..

Smartbear · Post by **Smartbear** » Wed Jun 03, 2020 2:02 pm

Jollyjoiner wrote: ↑Wed Jun 03, 2020 8:01 am Don't forget that these cars have regenerative charging systems so the alternator will only cut in and start to charge whilst the engine is slowing down i.e when you are braking. So, if your short journey is mainly all on the throttle then the battery will not get much charge.

They do charge at other times as well if needed, otherwise cars would be getting flat batteries on long motorway journeys when there’s barely any slowing down or braking going on

Rob

Jollyjoiner · Post by **Jollyjoiner** » Wed Jun 03, 2020 7:08 pm

Smartbear wrote: ↑Wed Jun 03, 2020 2:02 pm
Jollyjoiner wrote: ↑Wed Jun 03, 2020 8:01 am Don't forget that these cars have regenerative charging systems so the alternator will only cut in and start to charge whilst the engine is slowing down i.e when you are braking. So, if your short journey is mainly all on the throttle then the battery will not get much charge.
They do charge at other times as well if needed, otherwise cars would be getting flat batteries on long motorway journeys when there’s barely any slowing down or braking going on
Rob

Then I stand corrected

Nanu · Post by **Nanu** » Wed Jun 03, 2020 7:51 pm

Thanks Guys. A mix of ideas but on the whole battery on the way out sounds to be the concensus. Must admit for the sake of £30 I am tempted to see if giving it a charge makes any difference as I believe new batteries for the Zed are not exactly cheap, then there is confusion which again I dont understand around coded or not. On the good news front the last couple of week have given me the chance to do a full valet and it looks great.

Smartbear · Post by **Smartbear** » Wed Jun 03, 2020 10:13 pm

Nanu wrote: ↑Wed Jun 03, 2020 7:51 pm Thanks Guys. A mix of ideas but on the whole battery on the way out sounds to be the concensus. Must admit for the sake of £30 I am tempted to see if giving it a charge makes any difference as I believe new batteries for the Zed are not exactly cheap, then there is confusion which again I dont understand around coded or not. On the good news front the last couple of week have given me the chance to do a full valet and it looks great.

If it’s the battery not holding it’s charge so well, charging will only paper over the cracks & you also run the risk of the dreaded handbrake failure due to low voltage occurring and having to get updated software installed

A replacement battery of the same spec needs registering, a different battery will need coding

I’d keep an eye on the battery voltage after the cars sat for a few days, if it gets near 12v you’re on thin ice.
Rob

mcbutler · Post by **mcbutler** » Wed Jun 03, 2020 10:23 pm

I noticed that my glovebox light stays on when I lock the car if I leave the glovebox open! This accounted for my battery drain warning as I leave the car in storage for long periods regularly.
Also do you have a dash cam with a movenent sensor? If you do turn the camera off before you leave the vehicle in your garage.

Nanu · Post by **Nanu** » Thu Jun 04, 2020 8:02 am

Thanks butI have checked everything for the increased battery charge even unplugging Alexa I fitted and still get the warning so thinking its the battery.

As for which battery and posts such as "needs registering, a different battery will need coding" you may as well be talking Vulcan.

Judging by the differences in prices the internet appears to be the way to go rather than a garage but it would appear gone are the days when you just take the old one out connect up the new one and away you go.

All sounds scary.

Smartbear · Post by **Smartbear** » Thu Jun 04, 2020 10:31 am

These guys have been used by several owners from here with good reviews https://www.tayna.co.uk/
Rob

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