525d wont start

[sjp63]

Hi

Over xmas my 52 plate 5 series touring refused to crank, instead loads of quickly flashing lights on the dash.

Tried jump starting but same thing. Left jump leads attached to "charge" the BMW battery for 10 mins - started!

Drove to the shops and back (about 60 miles of motorway)all ok. Just tried to start it again (3 days idle) and same problem. Can probably jump it again but it seems there may be a slow drain on the battery from somewhere??

Any ideas?

thanks

Steve

[gazzab]

Put a new battery in!

[sjp63]

gazzab said:

Put a new battery in!

I was hoping for something a bit better thought through but thanks anyway

[off_again]

Actually, if a battery has had the charge drained out of it then it is unlikely to get it back again - even if it might seem to last, its unlikely to last more than a day or so. The more times that the charge gets low, the less chance it can be recovered. I work on the premise of "once its dead, its dead". So yes, the only real course of action is to get a new battery.

But, what could cause it? Could be a multitude of things. Basically, chuck a new one in and see what happens. Sounds crap, but the old battery could have been on its last legs, charging wise. So it worked fine until there was a bit of a drain on the battery and then gave up the ghost - they do give up. If this one starts to loose charge too - you will usually get 1 year free replacement anyway so it wont cost a bean - then get it to a dealer or electrical specialist. Something is draining the battery and needs to be checked.

I believe Derestrictor had a problem with his M5 along these lines and there were a few posts on what to look for. Personally I would let someone else do it (modern BMW's use a bus system which is a nightmare - its not a simple live and negative setup!). But there was a post saying what you could do DIY to check it out - try the search.....

[sjp63]

off_again said:

Actually, if a battery has had the charge drained out of it then it is unlikely to get it back again - even if it might seem to last, its unlikely to last more than a day or so. The more times that the charge gets low, the less chance it can be recovered. I work on the premise of "once its dead, its dead". So yes, the only real course of action is to get a new battery. But, what could cause it? Could be a multitude of things. Basically, chuck a new one in and see what happens. Sounds crap, but the old battery could have been on its last legs, charging wise. So it worked fine until there was a bit of a drain on the battery and then gave up the ghost - they do give up. If this one starts to loose charge too - you will usually get 1 year free replacement anyway so it wont cost a bean - then get it to a dealer or electrical specialist. Something is draining the battery and needs to be checked. I believe Derestrictor had a problem with his M5 along these lines and there were a few posts on what to look for. Personally I would let someone else do it (modern BMW's use a bus system which is a nightmare - its not a simple live and negative setup!). But there was a post saying what you could do DIY to check it out - try the search.....

Thanks I think Ive found it - maybe. Over the last couple of weeks on starting there has been a strange whistle like aircon thru a vent or something. Poking around today in rhe footwell I heard it louder and its coming from the LRC100 speaker. Disconnected the LRC from the mains and whistle gone.

Hope thats it - prsume LRC has developed short, probably at the lens unit.

Jump started ok.....wait for the morning to see if it starts or I'll have to take the Maser!

Steve