Alarmingly short battery life

stevieb · 6th July 2007, 00:09

I have been working on my 2001 M5 tonight, doing a DVD install & had the boot open, 1 door open & was playing a CD at normal volume (sounded failrly quiet outside). After about 1 hr, the CD cut out, & the battery was so flat I couldn't start the car

Is this normal?

I ran the car last night, so the battery should have been good. I also vaguely remembering that if the boot is open, I can hear the Satnav Cd drive 'cycle' when a door is opened does anyone else have this?

Steve

essex boy · 6th July 2007, 00:15

Ive had this problem, I've found that if I put my keys in my pocket I hit the buttons on key remote and sometimes my screen stays on, dont know how long 4 but now I check the screen is off and dont keep my keys in my pocket, battery has been fine. Also if you open the boot like you say the nav disc does keep going, I thought it was strange but after checking other posts I think is quite normal!!
Good luck.

jclyman · 6th July 2007, 01:56

How OLD is your battery?

timhur · 6th July 2007, 04:28

If your battery is the original it is time for a new one. you have gotten 6+ years of service.

stevieb · 6th July 2007, 09:04

No idea., but probably original. I would have thought though that the CD current drain wasn't that great & normally the engine cranks over fine.

Any recommendations for (UK) brands of replacement?
Steve

maxm5 · 6th July 2007, 09:20

Steve

I had to replace my quite recently. Would you believe it. The cheapest place and in my opinion, the best quality was from BMW!!!!

Shock horror. Only tried them as a last resort as no-one had the battery in stock.

£99.00 inc. ($200)

It takes about 2 mins to DIY.

jclyman · 6th July 2007, 16:49

Leaving just a door open (and interior lights on) for an hour or two (even leaving the glove box open overnight) with a battery near the end of its normal life is enough to drain it. Keep in mind, the battery still powers "stuff" while the car is off ... and, the starter takes a whopping amount of juice to start the engine. I would always have a trickle charger handy for maintaining the battery ... it's cheap insurance ... like 35 bucks.

BMWMPWR · 6th July 2007, 17:00

I agree with jclyman, a trickle charger/battery tender is "cheap insurance" however, I've had my system on while washing/vacuuming the interior for 1-2.5 hours with no issues. It shouldn't die that quick with a strong battery. Overnight, sure- any one of those could drain it, but an hour or so- time for a new battery as the others have suggested.

fvicente · 6th July 2007, 18:21

Quote:

Originally Posted by jclyman

Leaving just a door open (and interior lights on) for an hour or two (even leaving the glove box open overnight) with a battery near the end of its normal life is enough to drain it. Keep in mind, the battery still powers "stuff" while the car is off ... and, the starter takes a whopping amount of juice to start the engine. I would always have a trickle charger handy for maintaining the battery ... it's cheap insurance ... like 35 bucks.

don't know if you've noticed, but if you leave your door or trunk open for more than 10 mins the LCM shuts the lights off. Don't know if it does the glove box too, but have seen this many, many times while I work on the car. Granted, if the key is in the ignition (like when listening to the radio) the lights won't shut off, but I agree a 6+ year old battery is due. Also, beware replacements from the dealer- they don't last long IMO. I had one short out after 6 months with no signs of impending failure.

jclyman · 6th July 2007, 19:09

Batteries like almost everything else sometimes show up dead on arrival.

Purchased a Mercedes (from the dealer) battery and by the time I had gotten it home, battery acid (they had filled it while I waited) had leaked onto the floor of my other car ... Brand new, factory battery, with a leak in the case ...

That being said, I would still shop (dealers charge whatever they want for parts) for a genuine BMW battery, and with a battery tender you will get years of use.