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Can't Jumpstart Ascent!

10K views 16 replies 12 participants last post by  SkiPro3 
#1 ·
I'm the latest victim of the battery draining surprise hatch opening overnight. We've tried jumpstarting the Ascent (2020) with a jumper box and the battery will not take any charge. Instead, the lights on the interior and exterior flash like I'm at a disco. We stopped the process after 20 minutes because the lights kept flashing and no additional charge was gained. The battery is still dead (along with my plans). Any strategies or should we request a dealer tow?
 
#2 ·
Stop the dancing and get the tow to a dealer. The battery may not have sufficient charge for the battery to come back to life.

You might want to investigate why the hatch opened overnight to eliminate a repeat experience. also have the dealer check for any TSBs on this. I wonder if your 2020 production date was close enough to the 2019 such that the hatch module is the culprit. read a bit from this thread.
 
#3 ·
Be sure that your "jump pack/box" is being used properly - on some models, should the pack sense insufficient residual voltage in the battery, it will not provide sufficient power unless a safety mechanism (often called "boost") is first engaged.

Alternatively, try the old way with jumper cables, from a running vehicle.
 
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#4 ·
My wife and I were hit with the hatch dead battery "syndrome" while deep in the West Virginia mountains last winter. Road Assistance just brought a jumper box - but no battery cables - when they arrived. The jumper box likewise for us wouldn't start our 2021 Ascent Touring. Luckily a worker nearby had some jumper cables so we could get our car re-started. After returning home, I talked to my local Subaru Service Mgr, He supported me in replacing my under powered Subaru stock battery with an Interstate Battery - the mostest butt kicker battery ya got - model that since then has done the job through several camping trips etc that tax that hatch a lot.

Two things I learned:
1. Get a higher capability battery - as much as you can get for the Ascent size/class battery.
2. Don't store your battery jumper cables in the car's boot. If the battery dies, you won't be able to get to the boot to get your jumper cables out.
 
#6 ·
Alas, no, that does not solve the problem - it just mitigates the issue. If the liftgate controller or a bad or dying amplifier is draining the battery, it will eventually do the same to a new battery. The cause of the battery drain must be solved. After that (or at the same time), any battery that's been damaged by the drain needs to be replaced (and of course, if the battery has not been damaged, it does not need replacing, except as use-case needs require... for instance, I needed a bigger battery for my 9,500 pound winch).
 
#7 ·
I'm the latest victim of the battery draining surprise hatch opening overnight. We've tried jumpstarting the Ascent (2020) with a jumper box and the battery will not take any charge. Instead, the lights on the interior and exterior flash like I'm at a disco. We stopped the process after 20 minutes because the lights kept flashing and no additional charge was gained. The battery is still dead (along with my plans). Any strategies or should we request a dealer tow?
Gotta ask the obvious: Were you able to start the car?
 
#10 ·
@siullc when did you get the new battery, and did Subaru of America reimburse you? You have a 2019? How many miles? Do you have the extended warranty? Do you have issues with your liftgate responding? Have you had issues with ALL sound cutting out on the head unit?
 
#13 ·
Sorry about the delay Robert but I was traveling & I apologize for my lengthy response. I had my new battery installed on 3/28/21 (the car had approx. 7000 miles at that stage), I was traveling in AZ and called AAA since the battery was dead when I started the car in the morning & jump starting didn't help. I had driven approx. 45 miles the previous day before stopping for the night. I called Subaru on my drive back to Ca and the person I spoke to kind of blew me off, said I should have had it towed to the dealer right away and there was nothing they could do now that AAA had installed a new battery. I explained i had no time to go to dealer etc. as I was traveling. As far as I'm aware, I have had no issues with the tailgate although I had found information about a Service Bulletin on this board in 2020 from another kind poster (Power Rear Gate (PRG) Control Module- Design Change) & supposedly my dealer did whatever he had to do when I took it in for my 6000 miles service.
When I had time 10 or so days later, i did email Subaru about my battery issue and here is their boilerplate sorry, can't help you & good luck in the future response.
"Thank you for contacting Subaru of America, Inc. We appreciate you taking time out of your day to contact us.
I am sorry to hear of the concern you have experienced with the battery in your Ascent. The factory provided battery on most 2019 Ascent’s is rated at about 530 Cold Cranking Amps (CCA). This is the force needed to turn over the battery and is the reserve the battery would draw upon to turn over the starter. There are circumstances that may call for a battery with higher cold cranking amps or a battery charger. The battery can lose its charge due to the electrical components of the vehicle drawing from the battery. It is also possible that if the vehicle is not used on a daily basis or sits for longer periods of time that the battery will not charge fully. This is because the engine computer, transmission computer, and computer models for the airbags, entertainment system and security systems are all using a small but continuous electrical current supply. Some customers find that replacing the battery with one that has more CCA, provides a better reserve for the electrical system. If the car sits for longer periods in a private garage, you may also want to consider a trickle-charger.
Your Subaru retailer is your best source for technical assistance. We rely on their technical training and expertise. They also have the advantage of being able to physically inspect and test your vehicle. If you have further concerns with the battery I would suggest having the vehicle towed to the nearest retailer to have them inspect it while it is down, do not charge the car or replace the battery. I hope this information is helpful.
Be assured, your concerns have been documented in our database and are available for historical review should it be necessary.
We appreciate you taking the time to share your experience with us.
Sincerely,
(Name withheld by me)
Subaru of America, Inc.
Customer Advocacy Department
1-800-SUBARU3 (1-800-782-2783)
Service Request Number: 1-67709180253
 
#12 ·
If it hasn't been mentioned already: A very low battery draws a lot of current when you hook up to it for a jump start. That will be added to what the starter motor draws and toghether may be too much. If at all possible, I let the dead battery charge for a few minutes before trying to start the vehicle.
 
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