Battery drains every night

2010 HONDA ODYSSEY
140,000 MILES • 3.6L • V6 • 2WD • AUTOMATIC
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1ERALBRIGHT
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My battery drains overnight. It used to be more sporadic but now it's every night. Pulled all the fuses in the vehicle to find the parasitic drain, no change in reading. Tested the alternator output while running and under electrical strain-looks good. Battery is new. With the vehicle off and key out of the ignition, I tested with the multi-meter against the metal body of the starter solenoid and the disconnected negative terminal of the battery-about 12 volts. Would the short be in the starter solenoid, cabling or ignition switch?
Mar 17, 2019 at 5:15 AM
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ASEMASTER6371
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Good morning,

Parasitic draw is measured in amps, not volts. Current flow causes a drain.

https://www.2carpros.com/articles/car-battery-dead-overnight

You need to put a voltmeter in line on the negative cable and check the amp draw.

Roy
Mar 17, 2019 at 6:35 AM
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1ERALBRIGHT
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My multi-meter couldn't read amps high enough so I go another one. Now from the negative cable to the negative battery post it would read as high as 2.08 amps, then about 1.61 amps, then 1.05 before stopping at .44 amps. Same thing multiple times.
Mar 17, 2019 at 3:07 PM
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ASEMASTER6371
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Okay, when the modules go to sleep, the draw will drop. Usually around thirty minutes will put them to sleep.

When you test, it should be 50 to 75 milliamps.

.4 is way too high. That's when you remove fuses to see when the draw drops. Then you will know the circuit.

Roy
Mar 17, 2019 at 3:47 PM
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1ERALBRIGHT
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Checked the fuses again and found the draw dropped to nothing after pulling the #7 fuse on the driver's panel. Possibly related to the door latches, I read. Thanks for putting me on the right track!
Mar 17, 2019 at 4:31 PM
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ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
Mar 17, 2019 at 4:35 PM