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Battery Concern

35K views 67 replies 42 participants last post by  Robert.Mauro  
#1 ·
Had my Ascent in for the 6000 mile service. The dealer performed a battery test that measured only 214 CCA, OEM Reference is 530 CCA. Anyone else seeing results like this one?
 
#4 · (Edited)
A search will reveal quite a few threads on subaruoutback.org from owners who found the factory batteries on their Gen 4 & 5 Outbacks to be failure prone and weak. I was one of them. I'm betting that the cold weather and the passage of time will bring on the battery failure posts in this forum too. IIRC the Ascent factory battery has just a smidge more CCA than what they put in the OB.

The preferred upgrade is a Group 34 with the highest CCA or reserve capacity available, whichever your preference. Group 24 is bigger and fits better, but generally has a little less CCA/reserve.There is much debate about brands and types.

If I had an Ascent (not quite there yet) I'd be very inclined to cut to the chase and install a higher capacity aftermarket battery, instead of waiting for the factory weak-knees unit to fail in 2+ years, as they have done for me twice in an Outback (the original, and the OE warranty replacement). 2 bad Subaru can't get their act together on this.
 
#11 ·
A search will reveal quite a few threads on subaruoutback.org from owners who found the factory batteries on their Gen 4 & 5 Outbacks to be failure prone and weak.

NASIOC also registered the same kind of threads for the latest generation of WRXs.
 
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#5 ·
I’m taking my Ascent in today for a battery check. I’ve tested it and the lowest I have seen is 12.3 volts. It’s had some rough starts and with the temps dropping, there is no doubt in my mind that it will leave me stranded if not replaced.
 
#6 ·
Both my '15 Outback and my new Ascent had battery problems up front. Both were replaced. The Outback replacement was still running at 2.75 years when I traded it for the Ascent.
 
#8 ·
There are a few of us who got the factory battery replaced. Mine was replaced at 2,000 miles.

Mine had a bad cell in it and was only showing 10.5 volts when the engine was off. I full battery should show about 12.6 anything below 12 means your battery is practically dead.

A dead cell will cause longer cranks because the battery has less Cold crank Amps. Most have gotten their battery replaced with the retail version with a Blue Subaru sticker on it.
 
#9 ·
What was their recommendation?

The starter I've seen on 4-6cyl DOHC (or SOHC) uses 1,500W starter. Ultimately, the minimum cranking amp your starter requires is about 125A; another word, your battery has 1.7 times the capacity. Keep note of this for your future decisions.
 
#10 ·
I had rough starts couple of times and it's not consistent. Thought this could be related to the operation that consumes more battery amps after engine shut-off...like head lights ON for few mins or apply parking brakes or use tail gate. But I couldn't replicate the issue.

Also, anyone used battery warmer or engine block warmer in ascents?
 
#13 ·
Subaru really ought to upgrade the batteries they put in their vehicles. It's difficult for Ambassadors to keep a straight face when consumers ask them how long the batteries last on Subarus.

I looked at three or four pre-owned 2017-2018 Outbacks before I purchased one, and they ALL had battery corrosion that had seeped onto the mounting bracket. Both of our WRX's (2015 and 2016) required replacement batteries within 18 months of being purchased new off the lot.
 
#15 ·
Our August 2016 built Forester (non-turbo limited) will need another battery soon, can't leave the domelight on for more than 2hrs. I'm not sure where SOJ sourced their battery but the one we got is sure as heck worst than Autozone or Walmart batteries, and I bought and warranty/prorated a lot of batteries over the decades.
 
#14 ·
I believe that the vehicle self tests are draining the battery. Often I walk past my car in the driveway and I hear whirring from the rear or the front. I know that these are part of the car's systems checks but I've never heard it this often before from any of my other cars. If your setting for auto update is on, then that means the car os actively using wifi and pinging the software server at regular intervals to check. Given that the stock battery is possibly already weak, these two functions alone will kill your battery power,
 
#16 ·
The emissions item that you hear "whirring" happens on many newer vehicles, but I do agree that with all the electronics on new vehicles, it would be great if OEM batteries were better, maybe set the vehicle up for AGM batteries that can handle more drain and higher output alternators as stock equipment rather than people having to do it aftermarket.
 
#17 · (Edited)
OEM batteries seem to be a problem with a lot of manufacturers unfortunately. Glad they are not the sealed/maintenance free type which are a particular issue in Phoenix where heat evaporates or alters the electrolyte and the battery just dies with no warning. At least we can keep an eye on the water levels in these, but I'm going with my own battery at the first sign of weakness. Warranty is great if its a battery upgrade if not...
 
#22 ·
After reading the other posts on this thread, I took some readings on my Ascent today. I took delivery of my Touring in August, it now has 2880 miles on it. I would expect a new, fully charged, “12 Volt” low maintenance automotive battery to have an open circuit (no load) voltage of at least 12.6 volts, I’ve seem some noticeably higher. Unfortunately, batteries in modern cars never see a no load condition due to the need to keep electronics up and maintain some emissions equipment. These parasitic loads can be significant, especially on higher trim levels with more toys. I connected my trusty old Fluke 77 multimeter to the battery and clamped my Fluke 375 meter onto the bundle of wires on the negative terminal of the battery. After sitting for 24 hours at ~46 degrees, my battery voltage was 12.32 volts. As soon as I opened the driver’s door, the voltage dropped to 11.96 volts and continued to drop slowly. During starting the peak load was 233.4 amps and the voltage dropped to 10.18 volts. Once the engine started, the voltage came up to 14.36 on the fluke and my scan guage indicated 14.4 volts. I ran the engine for about five minutes and shut it down. The battery voltage dropped to 12.5 volts almost immediately and then continued to drop slowly. After I turned everything off and locked the car, the draw on the battery was 3.6 amps. By then it was cold and dark and I didn’t want to wait around to see if the load dropped of after a while. I did check the battery voltage on my wife’s 2014 Forester which has a 2 year old Subaru battery in it. It has also been sitting for about 24 hours, the voltage was 12.45 volts. My conclusion is that my battery is OK, not as good as I would expect a new battery to be, but not near death. Based on my readings, and the parasitic load I saw, if I was going to replace the battery, I would look for one with a higher reserve capacity than the stock battery. I’ll also make sure my NOCO Genius Boost HD GB70 2000 Amp 12V UltraSafe Lithium Jump Starter is stashed in the back.
 
#23 · (Edited)
Just an FYI of my own experience, I've got that same jump starter. the spec chart in the user booklet says it can be stored in temps minus 20 to plus 50 deg C average temp, whatever that means. But then there's a different statement in the product info booklet saying storage should be between 20-25 deg C. I have more confidence in the latter recommendation.
My read betw the lines is room temp storage to pull out for emergency use, and maybe very short term mobile carry in the vehicle when I can keep watch on the storage conditions.


I put a different brand li-ion jumper in a trunk last summer, forgot about it, and when I noticed it again a couple months later the case had split, I'm assuming from the heat as the car was often parked in the sun all day. I had stashed the jumper pack in the trunk to let me avoid replacing a battery in an old car for a while. Not smart or safe, lesson learned. In the future rather than try to string out a weak battery by carrying a backup, I'll just get a new battery.
 
#24 ·
Thanks for your comments. Consumer Reports ranked the GB 30, which NOCO doesn't show on their website anymore, as "fair" at low temperatures, which is why I got the larger GB 70 Hopefully it will get the job done if I ever need it when it's seriously cold. I've been using NOCO chargers for years with great results, so I decided to go with a brand I know and trust for the jump starter.
 
#25 · (Edited)
I'm also confident it will work well as a jump starter, and also I wanted more juice than the smaller model offers.



But I don't think it would be a good idea from a safety standpoint to store any li-ion jumper in the car all the time along with the other emergency gear. :smile:
 
#26 · (Edited)
I use a similar USB/Voltage display plug in my cars.
https://www.amazon.com/Jebsens-Charger-Battery-Monitor-Voltage/dp/B01N00I4TM
If my voltage (engine off) drops to below 12.1V, I give my battery a top off charge. Even a high quality battery's life will be drastically shortened, if your battery does not get fully charged. And nothing worse than draining a battery and not fully recharging it (12.7V) ASAP. And if your car is not frequently driven or just short trips, your battery will slowly drain, especially in the winter. Also of course be sure to never let the water get low.



If you keep your battery in good condition (even a cheap one), it will last 5+ years easily.
 
#35 ·
Every manufacturer include cheap batteries in their new builds....go to any website and you'll find at least one thread about a crappy battery..... that being said, you are spot on...... I experienced a dead battery in December after not being driven for a couple of weeks, I jumped and drove it on short trips and it wouldn't charge/hold a charge... took it in and the mechanic spent hours checking the charging system and the battery. It held a charge..... the mechanic asked what my driving patter had been He explained that driving on short trips under 30mph, the battery won't be charged..... in retrospect, the battery did well with little or no charge for many starts. Given all the electronics and passive system checks going on while vehicle is "off", there needs to be a higher capacity battery installed at build.
 
#28 · (Edited)
I had my battery replaced under the warranty today. My Ascent is six months old and has 3685 miles on it. The battery died over the weekend (The tailgate was left open) and after the Battery Minder charged it the battery showed a bad cell. Roadside Assistance gave me a jump start this morning and it was off to the dealer for a new battery and a six month oil change while I was at it. The Roadside Assistance driver recommended getting a Non-OEM battery as he sees 5 - 6 Subaru jump starts per week due to failed batteries. I put the Battery Minder on it when I got home and it still didn't have a full charge on a brand new Subaru OEM battery. What's up with that?
 
#31 · (Edited)
Just checked mine after it sat for 2 days after a 30 mile round trip drive.

12.3v ? in 65 degree weather. Roughly 60% capacity based on state of charge/voltage charts.

Looks like you can go with a slightly wider battery and still fit the mount. Any ideas which group size would work? Would have to ditch that jacket subaru made though ?
 
#34 ·
I got stuck at the airport with a dead battery after a five day trip. Dealer implied that I should expect that because it was cold - on a 6 month old vehicle. When they tested the battery it was bad and I got a warranty replacement.

It may have gone bad because of the design flaw on the power rear lift gate (that Subaru does not tell us about), where there is no possible way to leave the rear gate open without draining the battery. I’m very disappointed about the liftgate issue as I have dog crates in the back and have routinely left the back open on my Foresters for the last 20 years without issue. The culprit is a sensor that runs all around the lift gate that never stops worrying about the gate being open. Why it can’t time out like the lights and reactivate when the liftgate button is pushed is beyond me - it seems like a simple programming change.
 
#36 ·
I would like to know if there is any forum member who has first-hand experience with parking their Ascent, locked, whether at an airport or in their garage, for at least five days, after which the car started without issue. I parked mine for six days in my garage, locked, and it was deader than a doornail when I got back from a trip - no lights, nothing. Had to use the valet key just to open the door to pop the hood to jump it. After jumping it I took it to the dealer who tested it and said the battery was fine. I know others have had some issues, so I'm looking for someone who has parked it or at least five or six days, locked, and had no issues with it starting - assuming there is someone. Thanks.
 
#37 ·
I'm looking for someone who has parked it or at least five or six days, locked, and had no issues with it starting - assuming there is someone.
Mine sat in the garage for over two weeks, but it was unlocked. I do always fully turn off the radio and the fob is always out of range. No problem starting afterwards.