04 Passat battery drain?

In rec.autos.makers.vw.watercooled, Tom's VR6 wrote:

>
>Figuring a car battery is maybe 40 to 60 amp hours, we could easily
>lose 20 amp hours and still have a lot of power to start the car.
>
>20AH =20000 ma-hours.

Correction:
So 20000/40 = 500 hours
500 hours/ 160 hours/week => 3.1 weeks.

Now normally the draw is less than 40 ma, and the battery can spare
more than 20 AH, so normally it lasts longer.

If you are lucky enough to get the car when it's acting up, I have pulled
the radio and found the heat sinks to be very warm after the radio was off
all night. Same goes for amp.

"buschky" > wrote in message
...
> thanks for the detailed explanation. Now I'll try and debug the issue.
> David
> "Woodchuck" > wrote in message
> .. .
>> All the computers draw a slight amount of current when turned of. Such as
>> the engine & trans ECU, clock, radio, window ECU, etc, etc, etc. If you
>> don't lock the car, then it should live several months, maybe longer
>> before the battery gets drained to the point it can't start the car. If
>> you lock the car that kinda puts everything to sleep to save battery
>> life. I'm told even after so long the anti-thief red LED even stops
>> blinking. Never been told how long that is. MY 99 Passat sets in my
>> garage unlocked and key in ignition and I never had problems even after
>> several weeks. As for your car, you got a problem and I think it's going
>> to be a faulty battery(un likely) or like I said before it's the
>> radio/amp.
>>
>>
>> "D&LBusch" > wrote in message
>> ...
>>> If I'm understanding this correctly - the battery continues to drain
>>> unless the car is locked? Why would that be? I'm an old Air Cooled guy
>>> and I love this new Passat, but locking the car in my garage seems a bit
>>> much. Any other thoughts. I appreciate the dialogue. Thanks, David
>>> "Woodchuck" > wrote in message
>>> .. .
>>>> NO, once the key is off, it's off and I think the newer radios turn
>>>> themselves off after a certain time limit. But I have seen amps that
>>>> cause the drain. The difference between locking the car is about a
>>>> 5-10ma reduction in draw.
>>>>
>>>>
>>>> "D&LBusch" > wrote in message
>>>> ...
>>>>> Would the amp continue to drain while the key is in the ignition. If
>>>>> so, the fix seems as simple as just removing the key? David
>>>>> "Woodchuck" > wrote in message
>>>>> ...
>>>>>> Not twice in the same week. To reduce the battery drain to a min the
>>>>>> car should be locked so the alarm is set. I'm going to make a guess
>>>>>> and say the radio or radio amp, if it has one is causing your drain.
>>>>>>
>>>>>> "D&LBusch" > wrote in message
>>>>>> ...
>>>>>>>I have an 04 Passat. I usually leave the keys in the ignition when
>>>>>>>I park it in the garage. Lately the battery drains and requires a
>>>>>>>jump (twice in the last week). Does leaving the key in the ignition
>>>>>>>cause a batery drain due to something else running that I am unaware
>>>>>>>of? Thanks in advance - David
>>>>>>>
>>>>>>
>>>>>>
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