Increased Battery Discharge

[DR-JEKL]

Originally Posted by brownb_2

you shouldnt need to do this for any car.

car should use little no no jibbies from the battery when parked up.

im planning on leaving mine parked for up to 3 and a half weeks at a time.
do not expect to have problems with the battery.

i have done this with many cars without problems

but have you had a bmw before?

[brownb_2]

Originally Posted by DR-JEKL

but have you had a bmw before?

nope

do all bmws do this?

[jav_au]

I replaced the battery with the g14 Varta and this has stopped since. BTW the battery is an absolute bitch to remove and replace in this car. I tool it to the local battery world bloke and helped him our and we were both knackered after 45 min or so. The stupid short bracket that holds the battery in is designed so poorly!

[DR-JEKL]

Originally Posted by brownb_2

nope

do all bmws do this?

Like a lot of european cars these things have a lot of modules which draw power even when the car is shutoff. Over a period of sitting idle for a few weeks this can put a draw on the battery and if its less than healthy you will find you'll start having issues.

BMW actually sell a battery tender, i would recommend that you buy a ctek battery tender to keep your car on charge with if you leave it for a few weeks.

[brownb_2]

Originally Posted by DR-JEKL

Like a lot of european cars these things have a lot of modules which draw power even when the car is shutoff. Over a period of sitting idle for a few weeks this can put a draw on the battery and if its less than healthy you will find you'll start having issues.

BMW actually sell a battery tender, i would recommend that you buy a ctek battery tender to keep your car on charge with if you leave it for a few weeks.

most modern cars now have a lot of "modules"
these shouldn't be using anything significant

i stand by that for any car you should be fine to leave it sitting for that long.

i will report back when i have actually left my car sitting for that long

[s14_kev]

Originally Posted by brownb_2

most modern cars now have a lot of "modules"
these shouldn't be using anything significant

i stand by that for any car you should be fine to leave it sitting for that long.

i will report back when i have actually left my car sitting for that long

I've read that if you have CA (Comfort Access), you should store your key fob far away from the car if you're leaving it for extended amounts of time. From what I've read, if the key fob is nearby, the car will keep certain CA features active which draws more power.

If it's not possible, I've also read to store the key in the freezer while you're away, not sure of the validity of this though..

[DAL344]

My experience:
I drive 20 KM's to work each way per day + between 100-150 / weekend.
I use a CTEK charger monthly to fully charge the battery.
After about a week the stop start function stops working due to the battery not being fully charged.
The dealership haven't found anything wrong with my battery.
Make of it what you will.
My understanding:
I 'believe' the battery continues to work for a period of time after you switch the engine off. The battery doesn't start to be charged by the alternator until you have driven for a period of time - add the 2 up & short drives will cause the battery to discharge over time.

[American Dave]

I drive 30-40 kms per mon-fri and maybe 10 kms on the weekends. I don't charge the battery, I do have comfort access and radar/laser system installed as well. After 9 months I have seen no change or decline in charge. I do garage the car at home and work. Guess I have just been lucky so far.

[brownb_2]

said i would give an update on how my car goes sitting alone.

Have left the car for a period of 4 weeks with no problem at all.
Did nothing. just locked and put my car cover on.

started perfectly and no warnings.

[American Dave]

winner...oh and welcome back

[jmo]

Originally Posted by kevin///mlee

I've read that if you have CA (Comfort Access), you should store your key fob far away from the car if you're leaving it for extended amounts of time. From what I've read, if the key fob is nearby, the car will keep certain CA features active which draws more power.

If it's not possible, I've also read to store the key in the freezer while you're away, not sure of the validity of this though..

The keyfob works using RFID. There is usually an RFID reader near the handle of the car that works to a limited range. Its usually 1m or so. That allows for the automatic unlocking. If the range was any larger, the car could be opened after you walk away. As long as you don't keep the key to your car on a shelf next to your car, I can't see there be any issue here.

The freezer thing isn't anything to do with battery discharge as far as I'm aware. There are tools that thieves use to amplify the RFID reader range. So they stand next to your door handle with a device and it boosts the signal so that they can open your car while your key is inside your house. The idea of putting it in the freezer is the RFID won't penetrate a key surrounded by metal while its sitting in the freezer. You can also buy little RFID pouches for this purpose if you are paranoid.

[Macca74]

A couple of weeks back I returned from an overseas trip (2 weeks) and started getting this message as well. Have been driving it every day since and I thought it had gone away, but yesterday I got a low battery warning! I lock the car every night and the key is well away from it - no idea why this has started.

Guess I need to invest in a CTEK charger. Any recommendations on where to go for one in Melbourne?

[cplagz]

My car originally did this when I first brought it back from Vic and I was playing around setting up BlueTooth. Put it on a charger overnight and it has since gone away (for now)... this was ~3 weeks ago. I have a HAIGH charger. http://www.haigh.com.au/products/bat...arger-4-detail

[DR-JEKL]

Originally Posted by Macca74

A couple of weeks back I returned from an overseas trip (2 weeks) and started getting this message as well. Have been driving it every day since and I thought it had gone away, but yesterday I got a low battery warning! I lock the car every night and the key is well away from it - no idea why this has started.

Guess I need to invest in a CTEK charger. Any recommendations on where to go for one in Melbourne?

There was a seller on ebay selling them unboxed for $60 (just a basic battery tender) when I bought mine 3-4 years ago...

Alternatively Repco battery world all sell C-TEK, even the BMW item is just a rebranded C-TEK charger.

The battery could also be on its last legs, hence why the error message is still popping up. It might be time for a replacement!

[DR-JEKL]

Originally Posted by brownb_2

said i would give an update on how my car goes sitting alone.

Have left the car for a period of 4 weeks with no problem at all.
Did nothing. just locked and put my car cover on.

started perfectly and no warnings.

Happy days!

Albeit the biggest killer of batteries along with heat, excessive vibrations etc is constant draining...

So if you let the charge down by leaving it unattended for a month or so every few months this in itself can lead to premature wear of the battery.

[Macca74]

Originally Posted by DR-JEKL

There was a seller on ebay selling them unboxed for $60 (just a basic battery tender) when I bought mine 3-4 years ago...

Alternatively Repco battery world all sell C-TEK, even the BMW item is just a rebranded C-TEK charger.

The battery could also be on its last legs, hence why the error message is still popping up. It might be time for a replacement!

Thanks. From what I can see the MXS 5.0 seems to be around $109 on EBay at the moment - I assume that is the model I should get?

I am probably just living in denial and no doubt will buy one and then find out I still need to replace the battery, but it's probably worth having anyway.

[DR-JEKL]

this would do the trick

http://www.ebay.com.au/itm/CTEK-XS0-...item43bfce09dd

just read the latest repco catalogue, and lo and behold the ctek is on special for $59

http://catalogues.repco.com.au/catal...logue#pageNo=4

[Macca74]

Originally Posted by DR-JEKL

this would do the trick

http://www.ebay.com.au/itm/CTEK-XS0-...item43bfce09dd

just read the latest repco catalogue, and lo and behold the ctek is on special for $59

http://catalogues.repco.com.au/catal...logue#pageNo=4

Thanks for this. I note that the description of the charger says "Great for motorcycles, jet skis, ATVs and lawnmowers". Would this be too small for the M3?

[Ingenio]

I bought this one from Jaycar after getting some advice from Dave Dee... Works a treat!

http://www.jaycar.com.au/Power-Produ...arger/p/MB3606

[DAL344]

I had mine serviced yesterday...

It appears the module controlling the IPE exhaust valve may be drawing power 24/7 due to the way its been wired.

I'll keep using the C-TEK till I get it sorted...

[American Dave]

I know how to fix that, just leave the valve open and turn it off...

[DAL344]

Originally Posted by American Dave

I know how to fix that, just leave the valve open and turn it off...

It's an option but it'll mean the Minister for Finance won't go in it (could be a positive) & the neighbours will hate me more than they already do