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parasitic draw - Retained Accessory Power - draw on battery with ignition off?

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parasitic draw - Retained Accessory Power - draw on battery with ignition off?

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Old January 11th, 2018, 3:51 PM
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Default parasitic draw - Retained Accessory Power - draw on battery with ignition off?

I am tracking a parasitic draw on my battery (until I find otherwise).

What is the 'design' draw on the battery in Amps when the van is "asleep"?

FYI Chevy Designers On Crack: The lid on the fuse box is for access to fuses. All but tying it down with cables and hoses is counter productive.

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2003 Chevrolet Express 3500 Cargo Van; LQ4 6.0L V8

Last edited by tbb2; January 12th, 2018 at 2:52 PM. Reason: add info
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Old January 11th, 2018, 4:46 PM
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If factory everything, probably less than 400-500 miliamps
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Old January 11th, 2018, 7:03 PM
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QUOTE: If factory everything, probably less than 400-500 miliamps

I think you mean 40-50 mA? 400-500 mA would be 0.4-0.5 Amp.
I see generic references to parasitic draw testing that indicate anything over 50 mA is a problem.

I am looking for someone that has gotten this reading when there are no electrical problems.

Last edited by tbb2; January 11th, 2018 at 7:07 PM. Reason: clarification
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Old January 11th, 2018, 7:40 PM
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Miliamp, = 1000 of an amp, so doing remedial math 40-50 MILIAMP is 40- 50 ONE THOUSANDS OF AN AMP.
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Old January 11th, 2018, 7:41 PM
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Also written ma=miliamp
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Old January 11th, 2018, 7:56 PM
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Yes, but 500 ma is a half of an amp. It doesn't take a half an amp to run a clock and keep radio memory.
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Old January 11th, 2018, 8:41 PM
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Originally Posted by StanVan View Post
Yes, but 500 ma is a half of an amp. It doesn't take a half an amp to run a clock and keep radio memory.
Thank you
For those who are confused:
https://www.convertunits.com/from/milliamps/to/amps
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Old January 11th, 2018, 9:45 PM
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It should be less than 50milliamps. not sure what year you have.... the 2007 - 14 trucks go down to 10-15 mAmps in sleep mode.... the vans have a lot fewer modules than the trucks.
50 milliamps won't kill a battery overnight.

aftermarket remote start modules usually add 30 mAmps.
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Old January 12th, 2018, 11:58 AM
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Default parasitic draw - Blower Motor Resistor Assembly

tech2,

I have gotten to fuse 51 for the Blower Motor Resistor Assembly (BMRA) and the draw dropped to 0.004 Amp (4 mA). I was of the same mind that it should be less than 50 mA but 4 mA is much less than I would have expected ... not that I am complaining.

Looking at the BMRA the PN does not look original and there are a lot of aftermarket parts available. This leads me to believe the BMRA fails regularly.

In order to use the van until I get the BMRA sorted I want to pull the wide connector to disable it. On page 1-91 of the green manuals I see the wide electrical connector looks to allow me to do that by breaking the connection from the switch and fuse 51.

This is a hand holding question ... I do not trust the manuals or myself 100%. I am used to working with a comprehensive wiring diagram. Do you think or know if the wiring on these vans is so distinctly separated that fuse 51 and the wide connector are not interrelated with another system?
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Old January 13th, 2018, 10:34 AM
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i looked at a power distribution diagram. fuse 51 feeds the blower resistor high speed blower motor circuit and nothing else. this circuit is used when the blower motor is in the high position. when you turn the hvac switch to high it turns on a relay in the resistor. the relay closes the fuse 51 circuit and runs the blower on high speed. so pulling fuse 51 should only lose high speed for the blower motor and nothing else.
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