Battery light coming on then car cuts out...

confused2012

Hi

I recently purchased a 08 BMW 320D. Strangely when I put the key in and turn on the electrics (not the ignition), my battery warning light comes on after roughly 10 seconds and then after another 10 seconds the battery cuts out and switches off.

Any idea what is causing this???

Atlantic Dawn

Can you be clearer on what's going on, battery warning light would normally come on when you turn on the electrics, as would all warning lights.

confused2012

Hey

As in after all the lights go off with the key still in the ignition, radio on etc., the Battery warning light comes on after around 10 seconds and the car starts emmiting its beeping warning sound (same beep which would come on if diesel was low)
Then it cuts out after another maybe 10 - 15 seconds.

Is there such thing a 'weak' battery or something ?

Atlantic Dawn

Yes battery may be on the way out, could also be that your alternator is not charging the battery or that the alternator belt is too loose, on a new car it can be hard to know when the battery was last replaced or the health of it.
Have a look at the battery, should be inside the boot of the car on the rear side of it to see if there's any dates of manufactur on it, as a rule of thumb when the battery is 5 years old it's time to replace it, some will recommend replacing at 3 years.

biko

I take it that the car starts ok and drives ok?

confused2012

Cheers for the advice. Any idea how much a battery costs? I'm assuming it varies on the car.

And yes it starts and drives without any hassle.. Just frustrating to think it could decide to die at any time

johnayo

If the car is starting and running without hassle, it is unlikely to be the battery. Get the charging checked as it may be an alternator issue.

breadmond

You'd get one in halfords for about €120. As it's a diesel it needs a beefier one than a petrol car. I wouldn't worry too much about the car dying as you drive it, as long as your alternator is working you should be fine. It's starting on a cold morning when the weak battery will let you down

landmarkjohn

johnayo wrote: »

If the car is starting and running without hassle, it is unlikely to be the battery. Get the charging checked as it may be an alternator issue.

I think this is standard BMW battery low behaviour. It's letting you know battery is starting to get tired. My BMW car has been doing this for a couple of years, I will change when battery fails to start the car.

How long does your battery have left? No one really knows. But of course what you can't do is say "it let me down out of the blue".

aujopimur

Your local motor factor will load test the battery FOC.