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Posted: Apr 30, 2020

Subaru Battery Problems

Do you have a Subaru Legacy, Baja, Forester, Impreza, BRZ or some other Subaru model with a battery that can't seem to hold a charge? Join the club and know that your club membership isn't limited just to Subaru owners. There are a lot of car and truck owners who seem to find themselves struggling to keep their batteries charged. So what's going on? The two most-common scenarios for Subarus and other vehicles are a parasitic draw or how the car is being used.

A "parasitic draw" is a fancy way of saying there is something electrical in the car that is staying on when the car is turned off. An obvious example would be if you left an interior light on in your car. That light is drawing energy from the battery and slowly discharging the battery. If you leave it that way long enough and the light doesn't turn off on it's own, the battery will eventually run out of electricity and you won't be able to start your Subaru. Maybe you installed an aftermarket car alarm or stereo system. Even if it is properly-wired, an aftermarket car alarm system can significantly increase the parasitic draw on a battery.

Other accessories that create a parasitic draw include radios that might have a digital clock that stays on or memory for favorite station presets, but automakers anticipate those types of draws and make sure they are usually low enough that it won't impact battery performance. Many newer cars quickly go into a "sleep mode" after a fixed amount of time. This sleep mode helps reduce the parasitic draw on a battery, but many cars won't go into sleep mode if they have a key fobs located too close to the vehicle and this brings us into our second common scenario- how the car is used.

Did you always find yourself losing track of your car keys, but are now so happy your car has a push-button ignition that works as long as the key fob is within range, so now you leave a key fob in your glove box and just use the keypad entry to lock and unlock the doors? If your car only goes into sleep mode when your key fob is out of range, but you leave a key fob in your glove box, your car probably never goes into sleep mode.

Even if you drive your car every day, if your are significantly discharging your car battery whenever you aren't driving it with a parasitic draw, that will shorten the lifespan of your battery and probably your alternator, as it struggles to replace the energy consumed by your draw when you are driving your car. Do you take a lot of trips of short duration and/or relatively low-speeds? If so, then you may not be giving your alternator (the accessory that maintains proper voltage in your battery while you are driving) enough time to replace the energy that was consumed during storage and starting.

So what do a lot of people do when they run into these issues? Some call roadside assistance. AAA may come out, jump-start your car and send you on your way, but then you run into the same issue a day or two later. At that point, you're probably convinced that you have a bad battery, when the truth may be that your battery may just be deeply-discharged and even though you've gotten it started with a jump box or a pair of jumper cables, you haven't driven it long enough to fully recharge your battery.

What you really need to do is fully-recharge your battery with a quality battery charger and figure out why your battery is being deeply-discharged. If it's a parasitic draw, you need to figure out how to reduce that draw. If it's a key fob issue, maybe you need to make sure your key fob is far enough away that your car will go into sleep mode when you aren't using it. Maybe there is an unusual electrical issue that your mechanic will have to track down and address to correct your high parasitic draw?

Maybe it's just your driving habits that are causing the issue- you don't drive the car often enough or when you do drive it, you don't drive it at speeds or timeframes that allow the alternator to properly-maintain the battery. You could buy a new battery and you'll probably get one that is fully-charged (at least 12.6 volts) and work well for a while, but that just kicks the can down the road and you'll probably run into the same issue with that battery and it will probably happen sooner, rather than later. That brings us back to a quality battery charger.

Charging a battery seems like a no-brainer for some, but there are others who may be challenged to even pop the hood on their car, let alone hook up a battery charger and charge their car battery (many newer cars don't even have the battery under the hood anymore). We have a solution for you! Both the OPTIMA Digital 400 and the OPTIMA Digital 1200 Chargers are VERY simple to use. You don't have to figure out what amperage rate you should charge your battery at or how long you should charge it for, OPTIMA chargers do that automatically. All you have to do is push one button and the charger will take care of everything else. Even if you don't push any buttons, if you just connect the charger, it will eventually turn on by itself, analyze the battery, begin charging it properly and then go into maintenance mode, once the battery is fully-charged.

If that's still not easy enough, we can make it easier! OPTIMA chargers have optional ring terminal connectors. What does that mean? It means you can take these connectors to your mechanic and they can install them on your car battery, so all you have to do is connect your charger to these ring connectors (it's as easy as plugging in your smart phone to a charger) and plug in your charger to a wall outlet.

We would love to sell you a battery for your Subaru, but we don't want your battery business before you need to give it to us. If you keep your battery fully-charged to at least 12.6 volts whenever possible, you'll minimize the amount of battery business you do give us and we're just fine with that outcome and we think you will be too.

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