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Asus P5KPL-AM SE draining the battery in a few days

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First post, by konc

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Hi guys,
I've got this Asus P5KPL-AM SE LGA775 motherboard that drains the standard CR2032 battery in 3 days. I measure a consumption of 1-2mA with just the motherboard and its battery on a desk, nothing else connected, which I believe agrees with the 3 days duration.

My first step would have been to measure a diode expected in proximity in case it's leaking the wrong way, but I don't see anything I recognize as a diode in the area. I'm far from being an expert in these though so I'm asking for your help
1) To identify the diode I expected to find
2) To get any other ideas and suggestions, if I'm completely wrong about the diode

Here's a photo of the general battery and I/O chip area to get an idea, full board photos are in the retroweb link above

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and closer photos where I tried to make all components as visible as possible, please tell me if more photos are needed

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Reply 1 of 3, by majestyk

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I once repaired an Epox socket 7 mainboard with this exact issue. A tiny ceramic capacitor turned ot to be the culprit. It wasn´t shorted, but showed a small leakage current draining the battery within about 2 days.

Reply 2 of 3, by Yoghoo

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I had this problem a couple of times in the past as well. Like majestyk in one case it was also a ceramic capacitor. Took quitte some time to find and solve it.

This was on a 386 motherboard btw (see: Re: External and internal battery on a PCChips M321 motherboard draining very fast) but the issue is exactly the same.

Reply 3 of 3, by konc

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Ouch... I believe when you measure the resistance of capacitors while they are in circuit they are not always expected to eventually go up to infinity like they do when they are out of circuit. So how exactly did you guys discover the culprit, what measurement exactly was off?

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