Battery flat............

[amk2912]

Since getting the M3 I have hardly driven the 135i over the last 3 weeks (once in fact - about a week ago). Anyway, jump in there today to blow out the cobwebs and up comes the "battery low" warning and then the time and date resets.

Something must be drawing a bit of power when the car is "dormant" - certainly enough power to drain the battery after a week or two.

[Zuzu]

Originally Posted by amk2912

Something must be drawing a bit of power when the car is "dormant" - certainly enough power to drain the battery after a week or two.

Could be the M3 parked along side trying to pinch a bit of extra low down torque..

[d3syd]

Yes that doesn't sound right. Should be able to sit idle for a lot longer than that. Maybe you might have a dud battery.

BTW I would be unfaithful to my 1er as well if I had a M3 mistress

[amk2912]

Back in 1990 I had an '86 Magna that sat idle for 5 months (thanks mum and dad ) while I went to Europe. When I got home it started first time....but it had awesome flat spots on the tyres!!

[minijet]

Originally Posted by d3syd

Yes that doesn't sound right. Should be able to sit idle for a lot longer than that. Maybe you might have a dud battery.

BTW I would be unfaithful to my 1er as well if I had a M3 mistress

I agree.
Have just come back not too long ago from a month long trip and the 135 started up first go!

[Zuzu]

My neighbour purchased a new 320i sedan about 4 months ago, drove it around for 1 week, and hasn't driven it for the past 4 months..Its parked alongside my 1er in the carpark absolutely covered in dust...

Be interesting to see if it starts on his return from China, whenever that is..

[x5mad]

Originally Posted by amk2912

Back in 1990 I had an '86 Magna that sat idle for 5 months (thanks mum and dad ) while I went to Europe. When I got home it started first time....but it had awesome flat spots on the tyres!!

Yeah, these newer cars with fancy electronics just sap the battery. I had an e36 318 which I left untouched whilst I was on holiday for 3 months and when I came back the car started first time round.

I find that in my X5 if I forget to lock the car then after 1 week of not driving it there would be a high battery drain message. As I understand it, if you do not lock the car then the ECU will not shut down fully. I also find that the CD/DVD drive would mysteriously start spinning at random intervals as well. If I lock the car then there seems to be no problems.

Have you experimented with this?

[d3syd]

Originally Posted by amk2912

Back in 1990 I had an '86 Magna that sat idle for 5 months (thanks mum and dad ) while I went to Europe. When I got home it started first time....but it had awesome flat spots on the tyres!!

My boat sits idle for many months. Last Christmas day I took it out for a run after 18 months. To my amazement she started up first go as well.

Another story: When my previous Land Rover was about 3 months old, my car would occasionally fail to start for no reason at all. Turned out that it was a dud battery installed at the factory.

So maybe that's what you've got

[cargeek]

I'm sure X5mad is one the right track. I have had problems with the battery in my E91 and the dealer has asked me to make sure I lock the car at night so it can 'go to sleep'. I assume it could be worse if you have comfort access and leave the key within range of the car.

[amk2912]

Originally Posted by x5mad

I find that in my X5 if I forget to lock the car then after 1 week of not driving it there would be a high battery drain message. As I understand it, if you do not lock the car then the ECU will not shut down fully. I also find that the CD/DVD drive would mysteriously start spinning at random intervals as well. If I lock the car then there seems to be no problems.

Have you experimented with this?

Actually this is an interesting point. The 135i does sit in the garage unlocked. I have the battery charging at the moment for the next 24 hours or so. I will lock it and see if the problem re-occurs in a week.

Whilst on the topic of batteries and charging, I was under the impression that when you drive a car the battery re-charges. Is this so or do you have to drive from Perth to Sydney to top up a flat battery??!!

[Sprey]

ank2912, just curious. Do you have Comfort Access? I wonder if that feature has to keep 'polling' (ie checking to see if the key fob is in range) when the car is parked (locked or unlocked) and potentially put a drain on the battery over time?

[WOPALX]

Originally Posted by amk2912

Whilst on the topic of batteries and charging, I was under the impression that when you drive a car the battery re-charges. Is this so or do you have to drive from Perth to Sydney to top up a flat battery??!!

It was explained to me at with the efficient dynamics the car does not start charging the battery until it's fully warmed up. So in short yes you need to drive it a while for the charging to occur.

BMW also replaced my battery with a larger one and reprogrammed the car so it would start charging at a lower temp.... thus far no issues.

[BMW86]

Originally Posted by amk2912

Actually this is an interesting point. The 135i does sit in the garage unlocked. I have the battery charging at the moment for the next 24 hours or so. I will lock it and see if the problem re-occurs in a week.

Whilst on the topic of batteries and charging, I was under the impression that when you drive a car the battery re-charges. Is this so or do you have to drive from Perth to Sydney to top up a flat battery??!!

Mate I'm pretty sure you don't leave the key in in the fob when the engine is not running (regardless of whether you have comfort access or not) to charge the key. My other merc has the lego block key, same as the 135i, and the dealer said to never leave the key in the fob if your car isn't running as it will drain your cars battery in no time.

[Swift135]

If BMW's after sales is a good a Lexus you should get a new battery. My wife had a Lexus for just under 4 years when the battery died, they replaced it under warranty. Good thing as the genuine battery was about $900.

[CT135]

my MY02 WRX was the worst ... with the keypad immobiliser thing it had the battery would be dead after about 2 days of not driving it. I used to have to keep a jump charger battery kit in the boot! saved me a few times.

[x5mad]

Originally Posted by amk2912

Actually this is an interesting point. The 135i does sit in the garage unlocked. I have the battery charging at the moment for the next 24 hours or so. I will lock it and see if the problem re-occurs in a week.

Whilst on the topic of batteries and charging, I was under the impression that when you drive a car the battery re-charges. Is this so or do you have to drive from Perth to Sydney to top up a flat battery??!!

To keep the battery topped up it is recommended that at least once a week you have a journey which is at least 30 minutes long and is mostly highway cruising.

[BMWDave]

I recently went away for two months to South America. During that time, my 135i was parked at home. Dad took it out once just over a month into my holiday and it started just fine. When I came home, a month later, it also started fine. Sounds like something wrong with your battery.

[amk2912]

Originally Posted by Sprey

ank2912, just curious. Do you have Comfort Access? I wonder if that feature has to keep 'polling' (ie checking to see if the key fob is in range) when the car is parked (locked or unlocked) and potentially put a drain on the battery over time?

I do have Comfort Acccess. I would imagine if it was a polling issue everyone would have the same flat battery problem.

The battery was charged overnight and when I restarted it there was no "Battery Low" warning. I'll lock it this time and see what happens.

BTW - When I leave the car unlocked the key fob is not left in the socket.

If I get another flat battery issue I'll just get BMW Roadside Assistance to sort it out - maybe they'll put in a new battery....

[Swift135]

Originally Posted by BMWDave

Dad took it out once just over a month started fine.

But..... when you got home the tyres were bald.

[TimMc]

Originally Posted by BMWDave

I recently went away for two months to South America. During that time, my 135i was parked at home. Dad took it out once just over a month into my holiday and it started just fine. When I came home, a month later, it also started fine. Sounds like something wrong with your battery.

Ditto. I spent 9 weeks in Sth America earlier this year. Car was left locked. Started fine when I returned - though the tyres had lost nearly 15psi! Maybe battery's ok only if you're in Sth America...?

BTW, does anyone have a problem with their seats not reclining all the way

[cargeek]

TimMc does your car have comfort access? This has to be active even when the car is locked and it is always 'looking' for a key. I am sure this has something to do with the problem.

[RadiuM]

yee ole mans new SS had a "software" issue where it would keep the computer running while it was turned off and would cuase the battery to drain overnight.

a quick firmware upgrade and it was all good :P

the ss seats didnt recline all the way though, going to have to ask the dealer about that.