do not know how to check for a draw

2015 CHEVROLET SILVERADO
65,000 MILES • 6.0L • V8 • TURBO • 4WD • AUTOMATIC
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LOUIS PUGLISI
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  • 1 POST
My aftermarket Alpine radio does not turn off like it used to when I turn the key off. I do not know if that is a radio problem or the truck problem. It is a Duramax diesel so it has two batteries. I do not know how to check for a draw. I started turning the radio off manually and I thought that solve the problem for a while it was a week or two, but now it is doing it again even with the radio off.
Dec 1, 2018 at 2:15 AM
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ASEMASTER6371
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Good morning,

It does sound like you have a parasitic draw that is draining the batteries. Here is an article on how to test for a draw:

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

You will need a voltmeter with an amp meter. You need to remove the negative cable and put the red lead from the meter to the positive post and the negative to the cable. Let the truck sit for about one hour to allow the modules to go to sleep. Then check the amp draw. It should be 50-75 milli amps. If it is more, then you need to remove the fuses one by one until the draw goes to normal. Then you know the circuit that is causing the draw.


Roy
Dec 1, 2018 at 4:35 AM