>
> DW writes:
>>
>>I isolated where the short was. I was getting a 10 milliamp current flow from
>>the battery (and a 1300 ohm resistance accross the disconected battery leads)
>>with everything switched off and all fuses removed. The short is inside the
>>altenator. I have a less than infinity resistance accross two of the male
>>conectors (where the wires plug in) and the car earth. The third male conector
>>gives an infinate resistance. This third one is the conection to the warning
>>lamp on the dash.
>>
Jean Hertzberg writes:
> This sounds like a run around I put myself through some years ago. If you
> work it out, 10 milliamps will take more than 4 months to drain a 30 amp hour
> battery, although less to drain it past the point of utility..
I meant to post this when the original question came up, but didn't get around
to it. Trying to debug automobile electrical problems with a multimeter is
like trying to read fine print with an electron microscope; inconsequential
details completely obscure what you're trying to figure out. As primitive
as it is, the correct tool for automobile electrical problems is the test
light. In trying to figure out a current drain on the battery the thing to
do is to disconnect the positive battery lead and attach the ground clip of
the test light to the positive battery post. Then touch the 'probe' to the
positive battery clamp. (Got that? The test light is now in series with the
entire electrical system) If you've got a significant drain the light will
light up brightly, if not it won't. If it does light, debugging just means
pulling out fuses until it turns off, then tracking down that particular path.
Of course if it doesn't light, it means that your problem is something other
than a static drain.
The advantage of this approach is that it allows significant current to flow
which can allow a relay to click on and turn on the real power hog, accounts
better for nonlinear resistance components (such as light bulbs!), etc.
Joe
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