Battery drains overnight

2002 CHEVROLET SUBURBAN
350,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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SCOTTDANNY22@
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I did a test with my digital ohm meter between the battery post and the terminal connector on the negative side. The problem is the hood light comes on still. When I probe just the negative side to test it goes from 9.00 to 14.00 when the light comes on. Also, when I pull the fuse that says rdo amp it drops to 09. Any thoughts on this?
Thanks, Scott F
Aug 8, 2018 at 10:36 PM
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ASEMASTER6371
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Good morning.

When you are looking for a parasitic draw, you measure current draw, not voltage. You need to remove the negative battery cable and put one lead of your meter to the cable and one to the battery terminal. Set the meter to amp scale. Let the car sit for about fifteen minutes and see what the measurements. It should be 50-75 milliamps.

If it is more, pull fuses one by one until the draw comes down. That will tell you the circuit that is causing the draw. If it is normal, then it could be a shorted battery draining itself down.

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

Roy
Aug 9, 2018 at 3:24 AM
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SCOTTDANNY22@
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I did that and the fuse that says edo amp is the only one that made a difference.
Aug 14, 2018 at 9:09 PM
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SCOTTDANNY22@
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Sorry, RDO AMP.
Aug 14, 2018 at 9:10 PM
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ASEMASTER6371
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Please do not use caps. It seems like you are yelling at me.

That fuse powers up the radio. It is very possible that the radio itself is causing the drain. You would need to remove it and have it tested at a radio repair shop to confirm.

Roy
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Aug 15, 2018 at 3:27 AM
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SCOTTDANNY22@
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Okay, sorry about the caps this computer is stuck on caps something amiss with the keyboard just all of a sudden pure caps. Thank you. I was still looking for a vacuum diagram for a 1983 Chevrolet s10 1.8 v6 2wd manual transmission.
Aug 15, 2018 at 4:51 PM
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SCOTTDANNY22@
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Sorry, 2.8 v6.
Aug 15, 2018 at 4:51 PM