Subaru Battery Woes

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Has any Subaru owners gotten the dealer to replace the POS (I ain't referring to "positive") OEM battery under warranty?

If so, did they replace it with something better than the OEM?

Background:

While overnighting at my MIL's several weeks ago, my wife SOMEHOW managed to leave the rear hatch open. Don't ask.

In the a.m. that battery was D-E-A-D; DEDD.

My Solar BA9 formally pronounced it dead. My CTEK 5.0 MXS would not even begin the process. My newly acquired NOCO GB40 said, "amp it up." So, I bypassed the safeties and managed to get it started. Thank you, NOCO.

It idled in the driveway for 20 minutes, at which point I garaged it, connected the CTEK, and proceeded to re-charge and re-condition the battery.

The water level in the battery is fine, the starter and alternator are fine (according to the BA9), but while the "state of health" always reads 100%, the state of charge will drop to 17-31% within ten days, even with regular driving.

490 CCA isn't really that bad for that sized engine (2.5L). The reserve capacity of a battery impresses me more.

But this JC built battery impresses no one.

I have an appointment next week at the dealership for an exchange. I'm hoping to be able to talk them into a Duralast from the AutoZone across the street.
 
Originally Posted by dkryan
I have an appointment next week at the dealership for an exchange. I'm hoping to be able to talk them into a Duralast from the AutoZone across the street.



Subaru probably gets their batteries direct from the manufacturer by the truckload for likely under $50 a pop. No way are they going to comp you for a $100+ battery from someone else.
 
Is the money light on the dash lit? Charging is controlled by the ECU on modern cars. Could very well be something other than the battery. If you have a OBDII scanner, I'd be curious to know what the charge duty cycle is being commanded.

What happens if you charge it with the trickle charger and let it sit for a few days?
 
Originally Posted by atikovi
Originally Posted by dkryan
I have an appointment next week at the dealership for an exchange. I'm hoping to be able to talk them into a Duralast from the AutoZone across the street.



Subaru probably gets their batteries direct from the manufacturer by the truckload for likely under $50 a pop. No way are they going to comp you for a $100+ battery from someone else.


Similar experiences by Subaru owners indicate just the opposite, antikov. At least based on related posts in Subaru forums.

Stay tuned.
 
I'd also be curious to know what the parasitic loss is? If you have a multimeter with an amp clamp, you can measure that on the battery positive cable.
 
Originally Posted by ripcord
Is the money light on the dash lit? Charging is controlled by the ECU on modern cars. Could very well be something other than the battery. If you have a OBDII scanner, I'd be curious to know what the charge duty cycle is being commanded.

What happens if you charge it with the trickle charger and let it sit for a few days?


No lights on the dash.

And the BA9, CTEK, and NOCO aside, no OBDII reader!

Again, the alternator is fine. Maybe a parasitic draw from someplace else?

That's why I decided to go to the dealer first. That, before I invest in a battery outside the warranty (but, inside my wallet).
 
Originally Posted by ripcord
I'd also be curious to know what the parasitic loss is? If you have a multimeter with an amp clamp, you can measure that on the battery positive cable.


Yeah, as mentioned.

Heck, I have the BA9, CTEK, and GB40, so why not a multimeter?
I'd like to know the parasitic loss, as well.

I don't expect the dealer to do anymore "testing" than I did. But, I want to avoid a recurrence even with a new battery.
 
The battery that came in my Forester seemed extremely poor to me, I think I replaced it after two years.
The one in my daughter's Impreza seems to be a better unit for some reason.
I haven't looked at the one in my wife's Legacy XT yet, I think it is supposed to be something of a different animal due to the stop/start function.
 
TBH, nothing seems wrong with me for the battery. When she left the hatch open by accident, it turned on all the lights inside (if the system is similar to my 2015 Forester, thats 5 tiny incandescent bulbs). My wife left just one map light on, again by accident and it drained the battery by morning. It was hard for me to believe but Subaru's roadside assistance confirmed. These batteries are so tiny for this car that you really have to be careful or carry a jump starter. It doesn't last that long either (Panasonic one), 3 years tops. I didn't bother with OEM replacement under warranty as I just wanted to get rid of it.

@bbhero's suggestion of groups 35, be prepared to play around with the tray and the battery cover, not that easy in the case of Forester, not too sure of OB.
 
Just let them diagnose and hopefully replace it. They likely use the Subaru part since Subaru reimburses them with part and labor if covered.

Good luck
 
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Originally Posted by ripcord
I'd also be curious to know what the parasitic loss is? If you have a multimeter with an amp clamp, you can measure that on the battery positive cable.


+1. Knowing the draw in amps/ma over time is incredibly useful.
 
I replaced both batteries in my 2015 and 2011 subaru foresters around the 2-2.5year mark.
these were the even smaller 390?CCA batteries.

The 2013 outback 490cca battery lasted 5 years.

In their defense if you drain a battery extremely dead you can kill it. so its possible your wife damaged your battery.. just spend the money and replace it.

If your wife shattered her phone would you expect a warranty replacement?
 
Originally Posted by dkryan

...It idled in the driveway for 20 minutes, at which point I garaged it, connected the CTEK, and proceeded to re-charge and re-condition the battery...


It is highly unlikely you can charge a battery at idle. Many times our car batteries are being drained at idle. Our computers and electronics are taking
the volts/amps to stay operational leaving very little for the battery. If you revved the engine up to 2500 or so RPM's, then the battery would be able
to charge.

With my limited knowledge of how batteries work, I have much experience of leaving doors barely open or the leaving key in the "on" position and I know
my batteries are dead the next morning. Probably happens 3 times a year. I have one of those handheld jump starters thingy's in all my car trunks. Great Christmas gifts.

I think your battery is fine.

I listen to Lewis Altazan Podcasts (agco.com) and he recommends automatically replacing a car battery every 3 years. He considers it part of routine maintenance. With all the
trouble a bad/weak battery can cause, I'm starting to believe he is correct.
 
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If the car starts OK and there are no error lights on, they will correctly tell you that there is no warantable problem at this time.

The battery and the tires that come with a new car were specified on the principle that they only need to be good enough to get it out of the showroom.
 
I replaced the battery in our 2014 Outback after 1 winter. Although it tested ok at the dealer, the car seemed to barely turn over when it was below zero, and leaving a door open or a map light on even for a few hours in cold weather would kill it. Pretty sure I replaced it with a group 34, which performed much better in cold weather.
 
The word "warranty" has been part of this thread.
Does it matter to anyone besides me that the vehicle's build date, sale/in-service date and warranty expiration date be included?
It'd just paint a more complete picture.

Does a dealership use a load tester to check a battery?
I've heard it's THE WAY to test a battery. Then again, would they be square and honest with a customer?

Funny how things change. My 1995 Subaru battery got sold along with the car to a neighbor at 138K. It was a JC battery.

I'd LOVE to see 100 batteries of the same size from the same production run compared to death. I'd bet they vary.
 
My father's 2013 Legacy still has the original battery so I have to disagree as it being a POS.
 
Originally Posted by Lubener
My father's 2013 Legacy still has the original battery so I have to disagree as it being a POS.




Does your father's car have all the power equipment and accessories?

It's just a fact that all these electrical add ons decrease the life of a battery. Smaller batteries exacerbate the issue. It's not like the old days
 
In this era of computer technology, why don't all cars have battery rundown protection? Even my 2000 Mustang will turn off the dome light after 20 minutes or so. GM does the same. Don't know about Jeep, though.
That being said, I would just let them replace it under warranty.
 
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