Strange battery / electrical problem

Last week, I go out to use my car and the battery is completely dead. So dead even the car clock isn't functioning. I see from my receipts that the battery is 7 years old, so I figure I'll just replace it, which I
do. I get an Exide with 700 CCA (basically same model as I bought 7+ years ago; no problems). I drove the car for 10 min., parked it, and left it for a week. (BTW, electric windows, fan, etc. worked fine.) I come back this morning and it is completely dead--not even the clock was working (the same deadness that caused me to replace the battery).
At the garage, the mechanic tells me the alternator is putting out <13, that the minimum is 13.5, and that I need a new alternator. As far as the drain, he has no idea.
Now, the only thing I had happen to the first dead battery was a fuse issue. The fuse controlling the interior lights went out. I mistakenly popped in a 20 amp when it called for a 15. When the lights didn't work, I discovered my mistake, put in the proper fuse, and everything was OK. The car worked fine for a week, and then the battery problem.
So, any ideas as to what is draining my battery? This car is an '84 Audi 5000 wagon. The battery is in the back seat.
I know it's old but otherwise it's in great shape. I'd like to keep it around for a while longer. Appreciate any and all help. Thanks, Bill
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My '87 5000S had a low charging voltage problem. I traced it back to a poor connection at the field wire connection at the alternator. A small amount of resistance here can affect the charging current. If the alternator has removable brushes (my old BMW did) then this would cheaper and easier than replacing the whole thing.
As for the power drain, I suggest you disconnect the battery, charge it, then insert a multi meter (set on Amps) between the positive post of the battery and the detached positive cable. Read the drain -- should be no more than ~20mA. If it's more (greater than 10A may pop the fuse in the multi meter), then start pulling fuses one-by-one noting any change in the drain current. You may also have to pull relays. (Note that if the drain is large, then letting it drain for a while should warm up the fuse and/or relay, perhapsallowing you to find it with out removal.) Hopefully you'll eventually find a circuit with a minor short; if you do, then start disconneting devicee on that circuit, such as pulling bulbs, disconnect the big plug on the back of the radio, the master window switch (driver's door), etc. (the fuse panel cover should list everything on a given circuit).
Good luck! Jaz
PS, a buddy of mine thought he had a bad battery on his camper so he replaced it... then he decided he must have a power drain... until I pointed out that he had been leaving it on Accessory. Days later he decided that he indeed had a drain, and it was probably through a bad alternator diode, so he replaced the alternator... until I pointed out that the left-most key position was Accy, not Off. The upside is that he now has both a new battery and anternator. LOL.

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The test procedure should be followed. If I were to guess what you find it would be broken and frayed wires in the drivers door hinge area. The rubber accordion contains a lot of wires for multiple accessories and flexing breaks the wires. Some are hot all the time and if one of those shorts with a ground ...
Tony '91 100Q 5spd BTDT
Jaz wrote:

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wrote:

Oh yeah, I had that!
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Well, Tony, you nailed it! Thanks for the excellent advice. -bill
BG wrote:

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