ACG Fuse Draw
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ACG Fuse Draw
I'm having issues with a parasitic power draw of ~90mA which causes my battery to drain periodically. I grabbed my multimeter and hooked it up in series to the negative terminal and started going down the line to see which fuse lowers the draw. I pulled the ACG/Alternator fuse and bam, it dropped to ~20mA draw. I'm not sure what ACG stands for but since alternator is part of that fuse could it be the rectifier? Not sure on how to proceed, any advice is greatly appreciated.
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I'm having issues with a parasitic power draw of ~90mA which causes my battery to drain periodically. I grabbed my multimeter and hooked it up in series to the negative terminal and started going down the line to see which fuse lowers the draw. I pulled the ACG/Alternator fuse and bam, it dropped to ~20mA draw. I'm not sure what ACG stands for but since alternator is part of that fuse could it be the rectifier? Not sure on how to proceed, any advice is greatly appreciated.
The line that this ACG fuse is attached to "sees" several systems. So, any one of those maybe causing the parasitic draw.
Here's an article.
https://hondatheotherside.com/acg-fuse/
Joined: Jul 2014
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From: Chesterfield VA
How long is the car sitting between drives? How old is the battery? What's the battery voltage at rest neither charging nor discharging other than parasitic discharges for 24 hours?
90mA doesn't seem excessive. 0.090 amps will consume about 15 amphours a week which should not exhaust your battery in that much time. Battery typically has at least 50 amphours available. Two weeks gets iffy.
I haven't checked the parasitic draw on my S2000 but if will sit for more than a couple weeks I connect the battery charger.
Easy enough to fit a battery cutoff switch but then you'll need the radio code and the ECU may need to learn some things all over again.
Finally there's a device called Priority Start which will cut the battery when it drops to a certain voltage and retain enough power in the battery to start the car (pressing on the brake triggers it back on). Mainly intended for vehicles with radios and other electronics which may sit with the engine off but still using the radios. My Fords leave the power ports hot all the time and a couple devices (GPS, radar detector) would kill the battery if I neglected to unplug them. Honda cuts that power with the ignition.
-- Chuck
90mA doesn't seem excessive. 0.090 amps will consume about 15 amphours a week which should not exhaust your battery in that much time. Battery typically has at least 50 amphours available. Two weeks gets iffy.
I haven't checked the parasitic draw on my S2000 but if will sit for more than a couple weeks I connect the battery charger.
Easy enough to fit a battery cutoff switch but then you'll need the radio code and the ECU may need to learn some things all over again.
Finally there's a device called Priority Start which will cut the battery when it drops to a certain voltage and retain enough power in the battery to start the car (pressing on the brake triggers it back on). Mainly intended for vehicles with radios and other electronics which may sit with the engine off but still using the radios. My Fords leave the power ports hot all the time and a couple devices (GPS, radar detector) would kill the battery if I neglected to unplug them. Honda cuts that power with the ignition.
-- Chuck
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Joined: Dec 2021
Posts: 13
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How long is the car sitting between drives? How old is the battery? What's the battery voltage at rest neither charging nor discharging other than parasitic discharges for 24 hours?
90mA doesn't seem excessive. 0.090 amps will consume about 15 amphours a week which should not exhaust your battery in that much time. Battery typically has at least 50 amphours available. Two weeks gets iffy.
I haven't checked the parasitic draw on my S2000 but if will sit for more than a couple weeks I connect the battery charger.
Easy enough to fit a battery cutoff switch but then you'll need the radio code and the ECU may need to learn some things all over again.
Finally there's a device called Priority Start which will cut the battery when it drops to a certain voltage and retain enough power in the battery to start the car (pressing on the brake triggers it back on). Mainly intended for vehicles with radios and other electronics which may sit with the engine off but still using the radios. My Fords leave the power ports hot all the time and a couple devices (GPS, radar detector) would kill the battery if I neglected to unplug them. Honda cuts that power with the ignition.
-- Chuck
90mA doesn't seem excessive. 0.090 amps will consume about 15 amphours a week which should not exhaust your battery in that much time. Battery typically has at least 50 amphours available. Two weeks gets iffy.
I haven't checked the parasitic draw on my S2000 but if will sit for more than a couple weeks I connect the battery charger.
Easy enough to fit a battery cutoff switch but then you'll need the radio code and the ECU may need to learn some things all over again.
Finally there's a device called Priority Start which will cut the battery when it drops to a certain voltage and retain enough power in the battery to start the car (pressing on the brake triggers it back on). Mainly intended for vehicles with radios and other electronics which may sit with the engine off but still using the radios. My Fords leave the power ports hot all the time and a couple devices (GPS, radar detector) would kill the battery if I neglected to unplug them. Honda cuts that power with the ignition.
-- Chuck
Sorry for the late reply. I never got the notification of a new post. Normally I only put about 3k miles a year, so yeah it spends a lot of time in the garage.Turns out my battery was bad, got a new Honda unit, and ACG was not the issue. Checked additional interior fuses and found the interior and trunk lights wiring was drawing the additional juice. Oddly enough, today I installed the Izze pump simulator and noticed a black box and two sliced wires and antenna.... Turns out the previous owner had LoJack installed so I took that shit out and boom back to normal.
-Armando
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