Should I be concerned about parisitic drain when buying an outback - Page 7 - Subaru Outback - Subaru Outback Forums
 34Likes
Reply
 
LinkBack Thread Tools Rate Thread
post #61 of 72 (permalink) Old 03-30-2019, 11:20 PM
Registered User
 
Join Date: Feb 2015
Location: Oklahoma, USA
Car: '15 Outback 2.5i Premium
Posts: 2,059
Feedback Score: 0 reviews
Quote:
Originally Posted by jdupton View Post
It would seem that the BIU times out after about 10 to 12 minutes regardless of whether the key fob is inside or outside the car. The test may not be completely valid since the door openings and closings were not included in the test.

We would need someone to repeat a couple of these tests on a 2018 or other model year to see what, if any, differences in behavior may exist.

John
That's good information. It seems like Subaru has addressed a problem some people seem to have had.

I came across this in my 2015's Owner's manual while looking for something else:

Quote:
Never leave or store the access key inside the vehicle or within 6.6 ft (2 m) around the vehicle (e.g., in the garage). The access key may be locked inside the vehicle, or the battery may discharge rapidly.
They don't make clear whether it's the vehicle's battery or the fob's battery that warning pertains to. It's anecdotal, but being more careful to keep the keyless fob well away from the vehicle when not in use seems to have helped some who experienced dead car battery issues, at least before the '19s. As I said earlier, not leaving the fob in the car may solve ausdland's issue with his '18 with minimal effort.

skipw is offline  
Sponsored Links
Advertisement
 
post #62 of 72 (permalink) Old 03-30-2019, 11:51 PM
Registered User
 
russellpat's Avatar
 
Join Date: Aug 2016
Location: Lexington, KY
Car: 2017 Outback Limited 2.5, Twilight Blue/Ivory, Eyesight. Also 1995 BMW 525i with 240,000 miles
Posts: 1,761
Garage
Feedback Score: 0 reviews
Quote:
Originally Posted by skipw View Post
That's good information. It seems like Subaru has addressed a problem some people seem to have had.

I came across this in my 2015's Owner's manual while looking for something else:



They don't make clear whether it's the vehicle's battery or the fob's battery that warning pertains to. It's anecdotal, but being more careful to keep the keyless fob well away from the vehicle when not in use seems to have helped some who experienced dead car battery issues, at least before the '19s. As I said earlier, not leaving the fob in the car may solve ausdland's issue with his '18 with minimal effort.
Why would anyone leave a key in the car? Do you leave your wallet there as well? IMO, that is just inviting trouble even with an attached garage. In my case, I have a lockable detached garage with motion exterior lights and wanted security to be a bit higher.


Thank you
Russell Casey, 2017 Outback Limited 2.5, Twilight Blue/Ivory with Eyesight. Build date: 7/19/16. Purchased 8/5/16 in USA. Currently about 20,000 miles.
Added LED backup, cargo, door courtesy lights and Lamin-X yellow film on LED fog lights. Nushield Dayvue antiglare screen, Soundproofed front/rear doors, floorboard, cargo floor, tailgate & all wheel wells. 7/70 zero gold warranty


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
russellpat is offline  
post #63 of 72 (permalink) Old 03-31-2019, 01:54 AM
Registered User
 
ammcinnis's Avatar
 
Join Date: Jun 2014
Location: metro Kansas City
Car: 2015 Legacy Premium 2.5 CVT w/EyeSight+SRVD ... 2016 Outback Premium 2.5 CVT w/EyeSight+SRVD
Posts: 5,805
Feedback Score: 0 reviews
Quote:
Originally Posted by jdupton View Post
One other thing to note is that I read somewhere that the Outback is not specified as having 70 mAmps parasitic draw. That is instead the criteria the repair shops use for evaluation of whether further diagnosis is required or not.
TSB 07-85-14, Measurement of "Dark Current" (Parasitic Battery Draw), states in bold type:
Quote:
The maximum allowable average dark current draw is 70mA.
jdupton likes this.

"If you don't know where you're going, any road will take you there." ~ Lewis Carroll (Alice in Wonderland)


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
ammcinnis is offline  
post #64 of 72 (permalink) Old 03-31-2019, 09:04 AM
Registered User
 
Join Date: May 2014
Location: South Dartmouth, Ma / Killington, Vt
Car: 2015 Outback 3.6R Package 23
Posts: 1,321
Feedback Score: 0 reviews
Quote:
Originally Posted by russellpat View Post
Why would anyone leave a key in the car? Do leave your wallet there as well. IMO, that is just inviting trouble even with an attached garage. In my case, I have a lockable detached garage with motion exterior lights and wanted security to be a bit higher.

Back when I actually needed a key, I normally left the keys in the car when it was in the driveway. My house is in a private lane invisible from the street and the retired neighbors on the lane are better than a doberman for watching for intruders.


With keyless/pushbutton, it's more convenient to have the key fob in my pocket.
russellpat likes this.
GeoffD is offline  
post #65 of 72 (permalink) Old 03-31-2019, 10:07 AM
Registered User
 
Join Date: Oct 2018
Location: Ontario, Canada
Car: 2019 Outback 2.5 Limited w ES. Tungsten.
Posts: 112
Feedback Score: 0 reviews
Quote:
Originally Posted by russellpat View Post
Why would anyone leave a key in the car? Do you leave your wallet there as well? IMO, that is just inviting trouble even with an attached garage. In my case, I have a lockable detached garage with motion exterior lights and wanted security to be a bit higher.
We do have two key FOBs. When my wife and I drive together, we both have a FOB. I may take mine with me when we park, say to go to a movie, or to have dinner out. In those cases, my wife may choose to leave hers in the car. We still have one FOB to get into car, but car battery could drain unless there is some sort of safety built in.
MBGraham is offline  
post #66 of 72 (permalink) Old 03-31-2019, 05:01 PM
Registered User
 
Join Date: Oct 2012
Car: 2019 Subaru Outback Touring 3.6R
Posts: 207
Feedback Score: 0 reviews
Quote:
Originally Posted by ammcinnis View Post
TSB 07-85-14, Measurement of "Dark Current" (Parasitic Battery Draw), states in bold type:


The maximum allowable average dark current draw is 70mA.

That is a good TSB for reference. That statement also has a footnote for that section - it's not specific to the outback model. Might want to check it out for doing the testing... see attached.


To the original post - I haven't had any issues with letting them sit (4 different outbacks). longest times were 6 weeks at an airport and 7 weeks over this last christmas. Rotors get a nice sheen of rust that's annoying for a bit (bad here, worse at the coast where it sat), but no battery problems.
Attached Files
File Type: pdf 07-85-14.pdf (363.0 KB, 17 views)
jdupton likes this.
walker is offline  
post #67 of 72 (permalink) Old 03-31-2019, 08:34 PM
Registered User
 
Join Date: Oct 2018
Location: Ontario, Canada
Car: 2019 Outback 2.5 Limited w ES. Tungsten.
Posts: 112
Feedback Score: 0 reviews
Quote:
Originally Posted by walker View Post
That is a good TSB for reference. That statement also has a footnote for that section - it's not specific to the outback model. Might want to check it out for doing the testing... see attached.


To the original post - I haven't had any issues with letting them sit (4 different outbacks). longest times were 6 weeks at an airport and 7 weeks over this last christmas. Rotors get a nice sheen of rust that's annoying for a bit (bad here, worse at the coast where it sat), but no battery problems.
That's very interesting. But what does this mean and is it something an owner could do:
Quote:
Install the back-up power supply fuse then, (if applicable) using the SSMIII, confirm the
Body Integrated Unit (BIU) is set “Market Mode”.
If dark current is 70mA and acceptable drop in 48Ah battery is 50% or 24Ah, then battery would be 50% discharged in 14 days 24/0.07 hrs (But please check my math!) My car started after 12 days, but was dead after loading car with doors open and key fob nearby. In theory, wouldn't that mean 2 or 3 weeks max. Maybe the drain on earlier Outbacks was lower than current models.

This is of course just theory. Now that I am aware of the possible drain, I will just take reasonable precautions to ensure battery doesn't die on me!
Dantrax likes this.
MBGraham is offline  
post #68 of 72 (permalink) Old 04-01-2019, 01:24 AM
Registered User
 
Join Date: May 2018
Location: NorCal
Car: 2018 Outback Touring 2.5
Posts: 61
Feedback Score: 0 reviews
Quote:
Originally Posted by skipw View Post
I think that's highly likely. I don't have a car with pushbutton start, so can't check, though.

@jdupton may have a better answer soon. That's excellent information so far, John. 3A! Wow!! It would be interesting to know if the car ever goes quiescent while the fob remains in range after being driven; I'm guessing not, but that is just a guess.

In the meantime, ausdland, take the fob out of the car and store it out of range when you don't need it. Others can do a better job of defining how far "out of range" is, but I think I've heard 25 feet is adequate, less if there are several walls between the fob and the car.
I will take it out, away from the car and see how it goes.
ausdland is offline  
post #69 of 72 (permalink) Old 04-01-2019, 09:06 AM
Registered User
 
Join Date: Apr 2009
Location: Mid Atlantic USA
Car: '17 OB 3.6R Touring [ex-'09 OB Ltd. (2009-16); ex-'01 Audi A6 Avant (2001-2009)]; '14 Impreza Sport Premium
Posts: 818
Feedback Score: 0 reviews
It's an issue on any modern vehicle IMO, with the systems on board [parasitic drain].

A battery [jump start] pack is very useful & prudent imo.
Dantrax likes this.
fendertweed is offline  
post #70 of 72 (permalink) Old 04-02-2019, 12:55 PM
Registered User
 
Join Date: May 2018
Location: NorCal
Car: 2018 Outback Touring 2.5
Posts: 61
Feedback Score: 0 reviews
Quote:
Originally Posted by jdupton View Post
I just tested the length of a timeout for the BIU. When the car is locked and an active key fob is brought into range of the driver's door, the BIU wakes up and uses 3.10 Amps while the approach lights and interior map lights turn on. Once the lights time out at about 20 seconds (a configurable value), the current draw drops to 2.90 Amps for about the next 11 to 12 minutes. I was not standing there watching the current constantly but just checking it periodically with a timer nearby while I did other things in the garage. I ran two tests which were about the same but I didn't catch the exact moment when the BIU went back to sleep for either test.

After the 11 to 12 minute timeout period, the BIU went back to sleep and the current dropped back to 0.025 Amps with the active key fob still in range of the driver's door.

So, there is a timeout but it is not the one hour mentioned in the manual nor is it the 20 minute timeout for interior lights. It is different from both of the above.

I would then conclude that if everything is working correctly, leaving an active key fob nearby should only result in a limited amount of drainage of the battery for the 10+ minute period, at least for my car.


John
What about if the car is left unlocked in the garage with the fob in the car?

ausdland is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Subaru Outback - Subaru Outback Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Rate This Thread
Rate This Thread:



Similar Threads
Thread Thread Starter Forum Replies Last Post
4th Gen Outback - New Buyer Research burnedhog Gen 4: 2010-2014 63 01-07-2019 02:02 PM
Interested in buying 1996 Subaru Legacy Outback Probiz Gen 1: 1995-1999 3 03-08-2016 03:09 AM
Buying a Subaru Outback 04 iTweaQ Gen 2: 2000-2004 18 03-08-2014 03:50 PM
2010 Outback Complaints- NHTSA Decisions2make Steering Wheel Shake Issues 39 04-12-2013 02:33 PM
2004 Chicago Auto Show: I'm BAAAAACK!!! Kevin Trip Reports 51 02-19-2004 10:12 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome