[bmw] New battery failed?

[john <j.s.smith@xxxxxxxxxxxx>]

Sorry for this long post...

My '89 E30 325i failed to start last night - flat battery :-(
The thing is I bought the battery new from a BMW shop only 6 weeks ago, to replace the existing 
battery which had been in the car for 7 years! My problem is now that I don't know whether this new 
battery has actually failed in some way - or is there a fault on the car. btw I only replaced the old 
battery because that ran flat too.

What I have done so far:

1) Measured the current drain with ignition OFF and everything electrical in sight turned off. The 
current was about 2mA so I think that's ok

2) Measured the battery terminal voltage with engine running at 1000 rpm and most every electrical 
thing turned ON. The reading was 13.4 volts - so looks good to me.

3) The red battery lamp on the dash goes out as normal when I start the car so I *guess* is charging 
the battery?

The way the battery went flat is also strange... I used the car the previous evening, no problems. It 
was standing overnight, weather was warm. Next evening it was completely flat.

Also, the new battery is a sealed type and has a led indicator built into it. The label says 
green=ok, black (no light)= needs charging  yellow= replace battery. I've had this thing on charge 
for 10 hours and led is still off - although the battery voltage is 12.4V and I can take take several 
amps from it to drive a latge test lamp.

Is there an easy and reliable way to tell the charging current when engine running?

I don't want to look a right idiot by taking the battery back and then them telling me it's ok - so 
would appreciate some help with this.

Thanks

ps When I bought this battery from BMW it had a minor scuff mark on the side and wasn't in any kind 
of box - I just had the feeling maybe it had been lying around a while. Also the labelling on it says 
it's sell-by date is 4th April 04. Mmm
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