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I'm currently battling a dark current draw on my GMC Sierra pickup so it isn't just an Outback thing. I just recently started driving the truck again after it had been parked for quite a while. I had periodically put a battery maintainer on it while it was sitting, and made sure the battery was fully charged before I put it back on the road. The battery is an Interstate that is about two years old. I drove the truck for about a week and didn't notice any issues. Then I went to use it after it had sat about 24 hours and the battery was dead. I jumped it and drove it to town, leaving it running while I was stopped, and back home. I put my maintainer on it until it was charged again. The next day it was too low to start the truck again.

I decided to test for current draw with everything shut down, though at that time I was actually suspecting I maybe had a bad battery. One of my cheap analog multimeters was handy so I grabbed that, set it at the 500ma setting and checked the current. Promptly either fried the multimeter or most likely blew the internal fuse. Hmmm, maybe there is a current draw issue here. ?

In the second round I found my digital multimeter and found I have a 2.5amp draw with everything shut off. So yeah, 2500ma might have been a little much for the 500ma setting on my analog meter.
I suspect it might be related to the aftermarket remote start but it will take some testing. All I did so far was to pull two inline fuses right at the remote box under the dash but that didn't make any difference in the current draw. I guess the next step is to just start pulling fuses one at a time until I find out what circuit is the culprit. Unfortunately the high temp today is 3F with 10-20mph winds and the truck is sitting outside. I have a snowmobile and a quad in various states of disassembly in my shop so the truck is just going to have to sit for a little while.
Still not Outback related but I think the dead battery problem I was having with my GMC Sierra simply ended up just being a bad battery after all. I was never able to duplicate the 2.5 amp draw that I had but I spent a lot of time testing and retesting and pulling every fuse and relay individually while checking for current drain. I would show close to 200ma for a short time after shutting the key off but it always dropped way down after a few minutes. Along the way I did find a blown fuse for the left trailer light turn signal, which I had no idea had a separate fuse than the truck turn signal. I did pull three fuses for the remote start and the one for the Onstar system which have been known to cause battery drain problems on GMC and Chevy trucks in the past. But even with them in I didn't measure any excessive drain. It is still possible there was an intermittent drain in one or both of those circuits.

Anyway, the battery still didn't seem to be staying fully charged. I finally just decided to try a different battery and after I did I had no more problems. Even after sitting for a week the new battery was still right around 12.6 to 12.7 volts. Meanwhile I charged the old battery (not that old--Interstate MTP48/H6 that I had purchased new just over two years previous). I checked it every day not connected to anything and it showed good voltage for the first three days. Then on about the 4th or 5th day it was suddenly showing 10.6 volts-essentially dead. I charged it again and within two days it was back down in the 10.x range again. I charged it again and brought it to the shop where I had bought it to have it tested. At that time it didn't clearly fail the test but it also didn't react as a good battery normally would either. I left it there so they could charge it again just in case my charger wasn't giving it a full charge. I went back yesterday and he said this time it failed the load test immediately after being charged. I was still within the 30 month replacement so I left with a new battery.

Hopefully that was the problem all along, though I can't explain the huge 2.5 amp draw I measured initially that I could never duplicate again. I still have four fuses left out and I am going to try putting them back in one at a time and continue to monitor the battery voltage to see if it drops after they are reinstalled.
 

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2015 Outback 2.5i Limited, Ice Silver/Black
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I use one of these.
 
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2008 Subaru Outback 2.5I Limited w/VDC, HomeLink, remote start
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Just adding info from my recent Gen 3 post about parasitic draw. I have a peak draw of 130 ma. Tracked it down to the indicator light, whenever it flashes on the instrument panel. Fluctuates on and off every couple of seconds between 130 ma and 70 ma. Without the instrument panel fuse in place, the current drops to 40 ma. Wonder if this is something present in later gen models.

It’s a 2008 Limited with remote start. Hoping this is not an issue on the 2019 3.6R I just purchased today :|

It seems like all Outback gen’s suffer to some extent from relatively high parasitic current, at least compared to other major brands on the market. Wish Subaru would pay more attention to low power consumption in their circuit designs and electronic parts.
 

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2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
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It seems like all Outback gen’s suffer to some extent from relatively high parasitic current, at least compared to other major brands on the market. Wish Subaru would pay more attention to low power consumption in their circuit designs and electronic parts.
The measured dark current in both my 2015 Legacy and 2016 Outback is ~30 mA, with occasional short-term higher current demand. Though I haven't tried to measure it separately, current drawn by the security system indicator LED is perhaps 3 mA.

FWIW, the operating current of a typical indicator LED (like the security system tell-tale) is 20 mA or less. I'm not sure why you're seeing substantially higher spikes in your 2008; there must be something else going on at the same time.
 

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2008 Subaru Outback 2.5I Limited w/VDC, HomeLink, remote start
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Those values you measured make more sense. I've seen a lot of forum posts where people are claiming in excess of 100 ma draw as a baseline, though. Not sure how model dependent this all is. It would be nice if manufacturers released parasitic current values for car models (base configurations and with popular options).

One would think an LED indicator wouldn't draw more than about 20 ma. Is it possible there's an upstream coil relay that powers that electrical circuit? If so, I could see that eating up much more than 20 ma.
 

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2015 3.6R Limited w/ES
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...It would be nice if manufacturers released parasitic current values for car models (base configurations and with popular options).

One would think an LED indicator wouldn't draw more than about 20 ma. Is it possible there's an upstream coil relay that powers that electrical circuit? If so, I could see that eating up much more than 20 ma.
Subaru's FSM for my 2015 does in fact have a specification for dark current - it should be no more than 70 mA (pretty sure it's the same for all Gen 5s). My measurements on my 3.6R with a high precision clamp meter (not ideal - noisy reading) have typically been under 50 mA within 60 seconds of locking the car and moving the prox key out of range.
 

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2008 Subaru Outback 2.5I Limited w/VDC, HomeLink, remote start
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Good to know. Thanks for measuring @AvidHiker. I’m buying a certified 2019 3.6R Limited today and I’m having Flatirons Subaru (local Boulder dealer) run a parasitic draw test before I take it off the lot.

Coincidentally, I just noticed this morning that the CarFax report for the car I’m purchasing had “battery charging system” service performed at the 8K mileage mark, and the certified service at the 12k mileage trade in noted the battery was replaced. The car is just about at the one year mark.
 

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Follow the below mentioned advice and you will never have a problem.

Get a Group 34 battery or similar.
Keep fob 20+ feet away from the car when not in use.
Keep jump starter of your choice in the car at all times.
Get a trickle charger like the battery tender to connect to the vehicle when you dont plan to drive it for a week or two. Or connect it after a week or two.
 

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Keyfob-car spearation is something a few folks around here seem to obsess over, yet for no apparent reason except a couple anecdotal claims of related battery drain but with no real troubleshooting to actually confirm the cause. Based on my measurements over the years, my prox key range has always been within Subaru's published specifications (even with a brand new battery) - 6 feet, even unobstructed, is more than enough to allow the system to sleep. So, just FYI for new owners (IMO), there's absolutely no need to obsess over keeping the fob 10 or more feet away. It's also an easy thing to check if you have approach lights in the side mirrors - they will light up as soon as the prox key is close enough to wake the car up.
 

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2018 Outback 2.5i Limited, No Eyesight, No Navigation
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Discussion Starter #50
Keyfob-car spearation is something a few folks around here seem to obsess over, yet for no apparent reason except a couple anecdotal claims of related battery drain but with no real troubleshooting to actually confirm the cause. Based on my measurements over the years, my prox key range has always been within Subaru's published specifications (even with a brand new battery) - 6 feet, even unobstructed, is more than enough to allow the system to sleep. So, just FYI for new owners (IMO), there's absolutely no need to obsess over keeping the fob 10 or more feet away. It's also an easy thing to check if you have approach lights in the side mirrors - they will light up as soon as the prox key is close enough to wake the car up.
Obsessed is the wrong word. It takes zero work for me to place my keys inside far away, no obsession there. Meanwhile, there is zero reason to have my keys near the car. That is undesirable at multiple levels. What you call obsession is just people who are intellectually curious about the electronics of the proximity system. So, we are on this site discussing it.
 

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Obsessed is the wrong word...
As I said, and made perfectly clear, this is IMO. And a perfectly accurate description, also IMO - no need to fuel unfounded paranoia. Discussion is all well and good (who doesn't understand what we're doing here?) but when misleading statements are made, as I've said many times, I will never hesitate to correct them.
 
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