Parasitic battery drain?

2009 HONDA ACCORD
177,000 MILES • 2.4L • 4 CYL • 2WD • AUTOMATIC
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HONDA 2009
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My car battery drains if i don't unhook the cable overnight. 2.6-amp drainage and then i pull the 10a backup fuse the amperage drops down to 1.5 but not the acceptable 50 milliamp's or less. I am just wondering if this is the reason for the drain or to continue pulling fuses until it drops down to an acceptable amperage?
Nov 28, 2023 at 10:35 AM
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STRAILER
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Are you pulling fuses with the doors shut? Also, you must wait about an hour before doing any tests so the BCM will shut down. I have seen the driver's side MICU short out and cause a draw as well, but even more common is the A/C compressor relay stuck on, I would pull it to see if the drain stops.

Here is the location and a guide to help out as well:

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

Check out the images (below). Let us know how it goes.

Nov 28, 2023 at 11:16 AM
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HONDA 2009
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Yes, the doors are closed. If the battery cable has been unplugged the whole time, does it still have to go to sleep after I hook up the meter or after I am done driving an hour later, I should be able to unhook the negative and begin pulling the fuses, correct?
Nov 28, 2023 at 11:35 AM
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STRAILER
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Correct, can I ask how old the battery is? When a battery starts to go bad there can seem like there is a drain on it.

Here is a guide to help you load test the battery:

https://www.2carpros.com/articles/car-battery-load-test

Please go over this guide and get back to us.
Nov 30, 2023 at 9:53 AM
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HONDA 2009
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The battery is brand new, has been tested and fully charged. Also, a new alternator. New starter. I pulled the ac relay and no change. I let it sleep with the door buttons engaged and it drops down to .92 after about 30 mins. I pulled the 18 and 23 fuses accessory fuses on drivers side no change. I am still trying to figure out the drain. Any help is appreciated.
Nov 30, 2023 at 10:30 AM
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STRAILER
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Does this car have a CD player? If so, I have seen a CD get stuck and run the ejection motor to run the battery down. Also, check the glove box light. Is that .92 milliamps?
Dec 1, 2023 at 9:08 AM
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HONDA 2009
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I tracked it down to the fuse that controls the driver's side master door switch for the window control. I will be replacing the switch. Thank you for your assistance.
Dec 1, 2023 at 10:01 AM
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STRAILER
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Thanks for letting us know, we are here to help, please use 2CarPros anytime.
Dec 2, 2023 at 10:28 AM