Battery's Keep Dying

DSG2003Mach1

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Today when I went out to test it the car hadn't been turned on since yesterday so it sat all night and I just went out, opened my door, popped the hood (made sure I shut the door) and then disconnected my negative terminal but it was still reading 150 milliamps.

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Opening the door woke it up again if I understand correctly
 

TerminatorCobraJP

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If it’s the 5 amp fuse 39 in the fuse box under the driver side dash it’s for fused battery power to the GEM. Pulling that fuse eliminates multiple interior circuits. It doesn’t look like stereo system is on fuse 39 circuit.
Yes that is the fuse I'm talking about. I pulled it and my meter was reading where it should be. It's related to several interior circuits?

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Albatross

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If you disconnect and reconnect the battery terminal it wakes up when you connect the terminal and all the circuits get power.

It’s best to hook the meter up in series with the negative terminal to the battery. Close all the doors. Make sure everything is off and let it sit for a while. Do not touch anything. Don’t open the doors. Don’t cycle the locks. Nothing. The hood open won’t affect anything. If your meter powers of just cycle the switch to wake it up. Keep checking for a drop in current. If after an hour it hasn’t dropped below 50 milliamps (.050) then dig deeper.
 

TerminatorCobraJP

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If you disconnect and reconnect the battery terminal it wakes up when you connect the terminal and all the circuits get power.

It’s best to hook the meter up in series with the negative terminal to the battery. Close all the doors. Make sure everything is off and let it sit for a while. Do not touch anything. Don’t open the doors. Don’t cycle the locks. Nothing. The hood open won’t affect anything. If your meter powers of just cycle the switch to wake it up. Keep checking for a drop in current. If after an hour it hasn’t dropped below 50 milliamps (.050) then dig deeper.
So when I run the test I should leave the multimeter running and connected to the battery for 45+ minutes? What's the best way of attaching the lead to the negative post so that I don't have to stand and hold it?

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Albatross

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TerminatorCobraJP

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I guess I'll try to wedge this stick in between the post and some vice grips. I don't have an alligator clip.
20230320_211450.jpeg


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MG0h3

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JaCobro

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ninty9cobra

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Do you have anything connected to the gem module fuse? My brother had a similar problem with his 03 cobra back when he purchased it. The dealer installed a low jack security system to the gem module fuse and it would not let the gem module go to sleep and would drain battery after sitting for a couple of days.
 

TerminatorCobraJP

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Do you have anything connected to the gem module fuse? My brother had a similar problem with his 03 cobra back when he purchased it. The dealer installed a low jack security system to the gem module fuse and it would not let the gem module go to sleep and would drain battery after sitting for a couple of days.
I haven't done anything to the car that would mess with fuses. Although it came with an aftermarket styling bar with a brake light in it. Don't know if that involves fuse 39 in any way though.

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DSG2003Mach1

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RX1Cobra

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I’m definitely gonna test this, I always blamed the aftermarket alarm

Anyone ever figure out wtf that wire does?

Who’s the guy on here that does all the electrical diagnosis… drawing a blank on his username

I don't think anyone did. I did it a year or two ago and didn't notice any changes to the car. Except the draw was gone.
 

TerminatorCobraJP

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