<E34> <M5> flat battery?

[tom.peacey@xxxxxxxxxxxxxxxxxxx]

Hi,
I went to start my car yesterday and nothing happened
when I turned the key!  The OBC was dead, the service lights
and the interior light were flashing on and off and when I took the
key out the handbrake warning light was still lit (with or without the
handbrake on!).   The interior fan didn't work and the headlights
were very dim.  It was ok last time I drove it and I've done long
trips recently so the battery was fully charged.....also all of the
fuses looked fine.
How do I get to the battery anyway?  Is it under the back seat?
Is this normal behaviour (flashing lights!) with a flat battery on these
cars?
Thanks in advance for any help!
Tom
'92 M5 3.8

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