In article ,
Adrian Brentnall wrote:
Just a thought....
If you have a voltmeter of some sort - connect it across the 12v mes
bulb in the above setup.
Naturally, there'll be a voltage drop across the bulb when the door is
opened, but is there any volt-drop across the bulb when the door is
closed..? If there is, that indicates that there's a small current
'leaking' through the interior light, via the door-switch.
Car batteries are designed to provide lots of current for a short period
of time, to start the engine. They're not good at long-term supply of
smallish currents... - and the car ammeter won't indicate accurately
down at that level...

Come to that - can you put a test meter across the in-car ammeter?
With everything off there should be no voltage. A sensitive voltmeter
will tell you if there's a small current being drawn from the battery,
even when everything on the car is 'officially' off..

If you have an accurate voltmeter to measure millivolts, it's likely part
of a DVM that can also measure milliamps directly.

I really don't see how you can expect to do any fault finding on electrics
without a DVM. And even one at a fiver is better than nothing.

--
*I don't suffer from insanity, I enjoy every minute of it *

Dave Plowman London SW
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