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Subaru Outback - Warning lights

What does it mean when the brake light and battery light go on at the same time - Subaru Outback?

It means that your alternator is failing. I know that this is counterintuitive, but it is the reality of the combination of those 2 warning lights.

I would suggest getting the car to a mechanic before you kill the battery and before you become stranded.

Could it be something less expensive than that? Or is definetly the alternator?

Thank you

Most auto parts stores will test the battery and alternator free. Don’t guess; find out. It only takes a few minutes to test the alternator.

If the alternator is faulty the battery won’t last very long. Don’t delay. Have someone test the alternator ASAP before you’re stranded somewhere.

Trust me.
Been there, done that.
It IS the alternator.

The longer you delay in search of the answer that you want (rather than the correct answer), the greater the probability that you will kill the battery and become stranded in an inconvenient place, thus needing a flatbed truck to get you to a mechanic. Remember that your Subaru cannot be safely towed!

The possible good news is that alternator replacement might be covered by Subaru.
On my old '97 Outback, the alternator failed (after producing the same symptoms as your car) and even though all warranties on the car had expired long before, the dealership announced that there was no charge, as many Subarus of that era had also suffered from alternator failure. It turned out that the supplier of alternators had manufactured a run of bad ones, and because they had to make monetary amends to Subaru, Subaru provided free repair to its customers.

You did not provide us with the model year of your Outback (ALL details on a vehicle should be provided when asking a question!!!), so I do not know if your car is one that might be covered by the “free replacement” policy.

However, if you call the dealer’s service department and provide them with the VIN, they can tell you if you are covered for free alternator replacement. Then, no matter whether you take it to the dealership or to an independent mechanic, get this taken care of immediately because otherwise, you will be stranded within a matter of a day or two.

It is an '02 Outback - I bought it used 2 years ago and have had so many problems wtih it. Just spent 2K this year and last year 1,500 on a transmission, so I am just scared.

Thanks for all the help -

My '02 Outback has been even more trouble-free than my '97 Outback was, thus leading me to believe that yours was poorly maintained (or not maintained at all) by the previous owner.

For instance, if the transmission fluid had been changed at 30k and at 60k–as it was supposed to–it is very unlikely that you would have experienced transmission problems. My old '97 Outback, which is now in the hands of a relative, has over 160k on the odometer, and the transmission is still working flawlessly. My '02 Outback continues to operate like new in every way, most likely because I maintain the car very carefully.

After you take care of the alternator problem, I would strongly suggest that you take a look at the maintenance schedule that is (hopefully) sitting in the glove compartment. Make sure that ALL maintenance is up to date, including the timing belt if yours is a 4-cylinder model. Remember that all maintenance procedures have an odometer mileage value AND an elapsed time value, with the proviso, “whichever comes first”.

Even if the previous owner did not maintain the car properly, you can limit further damage by trying to play catch-up with maintenance at this point.

Thanks everyone for all the help. I was able to get to a mechanic today and it was as you said the alternator. Not happy about spending the money but it’s fixed and I’m not stranded.

As far as things being taken care of - yes, good point. Just frustrated, not upset with Subaru.

Glad to hear you got it fixed and hope you don’t have any more troubles for a long time now. The reason the warning lights turn on is due to the design of the warning light circuit. They are tied to the alternator field circuit and this allows the lights to be tested when the the key is turned to ON.

I’m glad that I was finally able to convince you that the alternator was on its way out.

Now, please follow up with my recommendation that you go through the maintenance schedule and make sure that ALL of the maintenance for the car’s odometer mileage and/or the age of the vehicle has been taken care of. It DOES make a difference, and it will be cheaper in the long run than having to replace failed components.

i am having the same problem. The battery tests out OK and the alternator is putting out about 12.75 volts. I seem to recall that 13.5 is recommended so is 12.75 enough difference to make the battery light come on and the battery to discharge while driving?

Yes… 12.75 is far too low and will not charge the battery.

Well darn the luck…Thanks

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