Defects in the Subaru's Electrical System Constantly Drain the Underpowered Batteries
- Owners of certain 2015 and older Subaru vehicles are constantly dealing with dead batteries.
- The batteries are underpowered, but not defective. Instead there appears to be a parasitic drain that draws power from the battery when the vehicles are turned off.
- Multiple class-action lawsuits allege that Subaru has known about this problem since 2014.
You're going to need a bigger boat battery
Too many Subaru owners are finding their cars with dead batteries and unable to start. The batteries aren't defective, but just lack the capacity to handle the draw from the car's electrical systems, particularly while the vehicle is turned off.
Some say their batteries will drain every few days, forcing owners to constantly jump their own vehicles or install trickle chargers at home.
The Batteries CAN Not Handle the Load ∞
The batteries are draining due to issues with the vehicle's controller area network (CAN). A CAN system helps all the electrical units, microcontrollers, sensors, and actuators communicate with each other.
The system is adequately powered while the vehicle is running, but should enter a sleep mode when the vehicle is turned off. But according to multiple class-action lawsuits, the system either doesn't have a proper sleep mode or has software errors that prevent it from properly conserving power.
Instead, the system continues to draw power from the battery which is known as a parasitic drain. By the time an owner gets back to their car, there's not enough power to crank the engine.
Subaru has allegedly known about this issue since 2014.
Replacement batteries are nice, but don't solve the problem ∞
To their credit, Subaru has offered to replace some dead batteries under warranty.
But the batteries aren't defective, they just don't have the necessary capacity and aren't designed to continually be drained down to low volumes of power. As the parasitic drain continues, the batteries lifespan is shortened. And there's only so many times it can be jumped before it just gives out altogether.
So replacing the OEM battery with another that has the same cold cranking amps, reserve capacity, and amperage hours, just won't work in the long term.
Subaru vehicles with drained battery problems ∞
The following vehicles have all had complaints about drained batteries, although the Ascent and Outback appear to have the most issues overall.
- 2019-2020 Ascent
- 2015-2020 Forester
- 2015-2020 Legacy
- 2015-2020 Outback
- 2015-2020 WRX
Lawsuits Regarding This Problem
Lawsuits about this problem have already been filed in court. Many times these are class-action suits that look to cover a group of owners in a particular area. Click on the lawsuit for more information and to see if you're eligible to receive any potential settlements.
Partially dismissed Tomasian, et al., v. Subaru of America, Inc.
Partially dismissed
After being consolidated with another lawsuit, the case was partially dismissed because some of the plaintiffs do not allege their vehicles continued to have problems once Subaru made repairs.
Case Filed
Subaru dead battery problems have caused a lawsuit that alleges 2016-2020 Subaru Outback and 2019-2020 Subaru Ascent SUVs are equipped with batteries that drain and die.
Partially dismissed Dalen, et al., v. Subaru of America, Inc., et al.
Partially dismissed
After being consolidated with another lawsuit, the case was partially dismissed because some of the plaintiffs do not allege their vehicles continued to have problems once Subaru made repairs.
Case Filed
A class-action lawsuit was filed because of battery problems in certain Subaru vehicles because the automaker's decision to install batteries with insufficient capacity to power the vehicle's electrical components when turned off.
Generations Where This Problem Has Been Reported
This problem has popped up in the following Subaru generations.
Most years within a generation share the same parts and manufacturing process. You can also expect them to share the same problems. So while it may not be a problem in every year yet, it's worth looking out for.
1st Generation Ascent
- Years
- 2019–2021
- Reliability
- 20th out of 38
- PainRank™
- 4.75
- Complaints
- 28
4th Generation Forester
- Years
- 2014–2018
- Reliability
- 38th out of 38
- PainRank™
- 21.02
- Complaints
- 353
5th Generation Forester
- Years
- 2019–2021
- Reliability
- 22nd out of 38
- PainRank™
- 5.21
- Complaints
- 38
6th Generation Legacy
- Years
- 2015–2019
- Reliability
- 24th out of 38
- PainRank™
- 5.72
- Complaints
- 82
6th Generation Outback
- Years
- 2015–2019
- Reliability
- 36th out of 38
- PainRank™
- 17.97
- Complaints
- 382
4th Generation WRX
- Years
- 2015–2016
- Reliability
- 35th out of 38
- PainRank™
- 13.79
- Complaints
- 60
5th Generation WRX
- Years
- 2017–2020
- Reliability
- 14th out of 38
- PainRank™
- 2.5
- Complaints
- 15
What Owners Say About This Problem
Twice my 2020 Subaru Ascent's battery has been dead. It has been driven every day for at least 20-30 minutes. Nothing was left on, or open. There is obviously an elecrical issue draining the battery.
This is the third time I have had to deal with a dead battery for the car. I don't drive it often, and the car runs absolutely fine when the battery is actually working, but the battery dies on its own which leads me to believe that it's somehow draining on its own. There has got to be a recall about this soon.
The battery has drained down twice in the same week. Car is only 6 months old. Nothing plugged in. Very annoying. I had Subaru Roadside Assistance tow it 45 miles to nearest dealer. We will see what happens. Clearly a defect in the 2019 Subaru Outback.