2001 bmw 330

hi all, i have a 2001 bmw 330. 36k miles on the clock.
i forgot to turn the lights off a few days ago and have been meaning to jump the car (i have another one so i didnt' bother straight away).
no i tried to jump it this morning and it won't start. the battery is "completely" flat and although when i connect up the jumper cables the lights all come on, AC starts etc it just clicks continuously and wont start
i didn't expect this to be such a big deal, anyone tell me if i'm doing something wrong and what i need to do to get this car back on the road?
rgds
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Try disconnecting the battery and going just with the jump battery and cables. If your battery is that flat it may be dragging down the jump voltage.
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daytripper wrote:

Or more likely you using crappy jumper cables. You'll need good ones to start a car with no battery, or with a completely flat one. Be prepared to buy a new battery. They don't like it when they are discharged completely. Escpecially when left that way for a while.
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Did you jump it at the battery in the trunk, or at the terminals in the engine compartment (like you should be)?
FloydR
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i'm actually jumping it at the battery in the trunk, not at the terminals in the engine compartment.. does it really make that much of a difference?
re: leaving the battery flat for a period, its been about 6 days since it went flat. i've never had a problem before, do people think i've killed the battery by leaving it for this length of time?
thx!
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Yes. True story: back in the days of metal bumpers, we couldn't get enough juice through the jumper cables, so we pushed the two cars together at the bumpers for the ground contact, put both cables on the positive and got enough current flow to start it.
You need every amp and all the voltage available. The terminal is 12 feet of conductor closer to the starter (and electronics.)

Leaving it flat/uncharged doesn't have much effect. It's the number of discharge cycles that matter.
FloydR
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got it going finally, it was just really flat so i had to leave the other car running for about 5mins before it would start. i didn't that just connecting up the other cars battery to my terminals would start my battery charging.. i thought that would just supply energy to the car and that only when i drove off would the battery start to charge.. live and learn i guess
anyway, thx to all
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