2016 WRX, drains battery from full to dead in 4 days

[gawainx]

I'm trying to troubleshoot a parasitic drain in my 2016 WRX ltd (eyesight)
After some trial and error I've verified that the battery itself is good but the vehicle has a significant parasitic drain

I've been going at the thing with a multimeter but am a bit intimidated sonfsr about either hot pulling fuses or continually disconnecting the battery in short succession.

There's about a [email protected] load on the battery with the vehicle entirely off and no lights lit.
I've found that the ABS system is accounting for about 250 MA of that but not sure where the other ~160 adbornmal MA may be coming from yet.

How much would troubleshooting something like this likely cost me, especially with the ABS seemingly involved.
Any guidance or thoughts before I dump too much time into this or screw something up would be much appreciated.

Could this be related to this pending class action suit?
https://www.google.com/amp/s/www.torquenews.com/1084/subaru-battery-drain-lawsuit-new-claims-now-include-forester-wrx-and-legacy/amp

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[Cougar4]

I don't know what a normal current draw should be in the newer model cars. I know the older ones had around 25ma for a normal current draw after things went into the sleep mode. I would guess that a normal draw should be something less than 80ma.

You have pinned down the ABS system for a large portion of the excess draw. I would disconnect the ABS controller to verify the draw is coming from it. As for the rest of the excess draw, are you leaving enough time for things to go into the sleep mode after you disrupt the power to that area? Pulling and replacing fuses to areas isn't a problem. You won't hurt anything. Keep pulling fuses until you locate the area for the rest of the current draw problem.

I can't say how much a new ABS brake controller will cost you if that needs to be replaced, but I would guess it isn't going to be cheap. There are places that sell rebuilt modules for a lot less than a dealer will charge you for a new module.

[Cougar4]

deleted repeat post

[gawainx]

Originally Posted by Cougar4

I don't know what a normal current draw should be in the newer model cars. I know the older ones had around 25ma for a normal current draw after things went into the sleep mode. I would guess that a normal draw should be something less than 80ma.

You have pinned down the ABS system for a large portion of the excess draw. I would disconnect the ABS controller to verify the draw is coming from it. As for the rest of the excess draw, are you leaving enough time for things to go into the sleep mode after you disrupt the power to that area? Pulling and replacing fuses to areas isn't a problem. You won't hurt anything. Keep pulling fuses until you locate the area for the rest of the current draw problem.

I can't say how much a new ABS brake controller will cost you if that needs to be replaced, but I would guess it isn't going to be cheap. There are places that sell rebuilt modules for a lot less than a dealer will charge you for a new module.

I wasn't giving enough time for things to enter deep sleep mode. After that the draw was around 25-30ma on my meter.
I've gone ahead and replaced the battery with an optima group 35 yellow top .

I've fully charged the new battery and have been popping the hood once every 24 hours to measure the voltage while the vehicle sits. It's been dropping about 0.06v a day or so which the other has been doing until it was down to 12.0 or even 11.8v
In this case I'm giving it more time and monitoring it just in case the battery hasn't fully balanced all of the cells just yet.

[Elbert Bass]

Originally Posted by gawainx

I wasn't giving enough time for things to enter deep sleep mode. After that the draw was around 25-30ma on my meter.
I've gone ahead and replaced the battery with an optima group 35 yellow top .

I've fully charged the new battery and have been popping the hood once every 24 hours to measure the voltage while the vehicle sits. It's been dropping about 0.06v a day or so which the other has been doing until it was down to 12.0 or even 11.8v
In this case I'm giving it more time and monitoring it just in case the battery hasn't fully balanced all of the cells just yet.

You are well below the allowable 70 mA Subaru specifies for dark current. In fact that is about what 90% of Subarus read when tested. A dead/dying cell in your battery will cause your initial concern - you should be OK with a new battery - unless the cars sits for weeks on end and only gets driven a couple hours on weekends.

[gawainx]

Originally Posted by Elbert Bass

You are well below the allowable 70 mA Subaru specifies for dark current. In fact that is about what 90% of Subarus read when tested. A dead/dying cell in your battery will cause your initial concern - you should be OK with a new battery - unless the cars sits for weeks on end and only gets driven a couple hours on weekends.

Brand new battery,
Optima YellowTop D35 (48AH)

The problem still exists with the new battery where it's losing about 0.06V every 24 hours, will drop from full charge (12.68) to barely able to start ~12.00 in less then 10 days.
Is this normal behavior for a 48AH battery with 30MA parasitic drain?

When I do the math it should take more then 66 days for 30MA parasitic drain to kill the battery, so it shouldn't be outside of the starting voltage range at less then 14 days unless the vehicle is periodically coming out of sleep mode or something?

I'll need to reach out to Optima next week to get the discharge curve for this battery.

[gawainx]

Welp, it's possible the new battery may have fixed it, I'll need to lookup what the discharge curve is for it.
While the optima dropped about 0.8v. A day for the first 3 days, it stayed at 12.51 the 4th and 5th day, so perhaps it just needed 72 hours to balance the cells after being charged or to rest? I'm going to continue testing it another week but that was pretty promising.

[PilotKD]

Got this in the mail today:

https://www.subarubatterysettlement.com/

[PilotKD]

Got this in the mail today:

https://www.subarubatterysettlement.com/