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Discussion Starter #1
The other day i turned off my car for a couple of minutes, came back inside interior lights went on it opened fine, beofre you know it i stick the key in and turn and the battery is dead... I had issues before hwere my battery had bad contact with the connection but i tightned it... after words i opened my trunk played around with the connection and all was fine... what can be the issue??

When i turned my key allt he way i had that light with the boat.... What exactly can be my problems,? was it just a bad connection or do i need to replace my battery...

Thanks
 

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"that light with the boat"? I'm assuming that is a typo - and hope like hell you aren't talking about the oil pressure light.

If you drain your battery fully (to the point of not being able to turn the car over and hearing just a faint click) you need a new one.

d-
 

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Confused me too - light with that boat??

Any chance you could put a picture up?

In my case when I had what I think was a similar problem it was that connections that were at fault, I removed the battery connections, cleaned the terminals very well and re connected everything making sure they were tight - never had a problem since.

But, as Doug says, if your battery has been drained fully then you will need a new one.

If your car is over 7 years old I would go ahead and replace the battery anyway.
 

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Discussion Starter #6
Can i replace it with an optimum...?(optimum yellow top, red top)

Or do i need to go OEM?
what are my options?
 

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You are probably facing a new battery, but for years (like over 20), BMWs have a circuit that cuts off the electrical current after it gets to a certain low level ... to protect sensitive electronics. If you recharge with a very SLOW CHARGE, it may come back and be fine (depending on how old the battery is). Used to happen to my Mother's 528e (1988) fairly often (she would leave the door not fully closed and not go out to the car for days). The battery still lasted for a long time, I just had to slowly recharge a few times. (The battery terminals were clean and tight.)
 
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Does your battery have the "eye" or light on top? Something like green = good, black = needs recharge, yellow = bad?

I was working on my car last weekend, had the hood/trunk open, and was playing with the fog/headlights a little. After 4 hours of the door/trunk being open, the car wouldn't start. Seemed odd to me, but I put a battery charger on it and it started right up.

My battery light was black though, I haven't checked it since to see if turned green.
 

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Does your battery have the "eye" or light on top? Something like green = good, black = needs recharge, yellow = bad?

I was working on my car last weekend, had the hood/trunk open, and was playing with the fog/headlights a little. After 4 hours of the door/trunk being open, the car wouldn't start. Seemed odd to me, but I put a battery charger on it and it started right up.

My battery light was black though, I haven't checked it since to see if turned green.
Black is NOT good. Should be green and stay green unless it sits a long time, in which case it would eventually turn to black again. Black doesn't mean the battery is "toast," it just means it is discharged too much. (Of course, it also turns black when the battery is dead.)

Your battery "could" be marginal ... I'm not sure how long you can putz around with the doors open. But, the circuit protector probably turned on to keep the battery from damaging any electircal items ... A SLOW charge will bring it up to the point (it doesn't have to be fully charged to start) where it is above the voltage where the circuit breaker kicked in. A "jump start" should be avoided in this situation. A jump start after the voltage is high enough, might be OK, but I would still avoid it.
 

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If im certain of one thing about bats is: Once they start failing thats it just go ahead and change them.
You can sort of tell when the bat is low when you fire her up specially, you will be amazed at what a new bat can do, all the lights, ignition, interior lights etc.. everything seems to work better and look sharper. IMO.
 

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Discussion Starter #12
so you think i can go with an optimum... those battieries have a life time warranty and i used them for all my other cars, never had an issue... You can leave you lights on for as long as you want its a battery garanteed never to die... Retails for about $120-$150

How much is the oem battery?
 

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Roughly the same amount - varies by dealer.

Just remember to get the right Optima - you need 800+ CCA. I seem to recall the Optima was about $150. I also recall a 6 year or so warranty, not lifetime...

d-
 

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Discussion Starter #14
i bought a yellow top optimum for my last car, the salesman told me it was a lifetime, never really looked into it though but maybe your right
 
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