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Discussion Starter #1
I have 2001 outback 3.0
The battery symbol and brake light come on the dash but then go off. It puts out 14 volt more or less when running. When the lights came on the dash the voltage dropped to about 11.8 volts.
It looks like the alternator but could it be something else? I thought once the alternator goes it goes.
 

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2003 OBW 2.5L 4EAT
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I believe the alternator output value should minimum of 13.8v at idle and it should stay around 14v otherwise, so definetly looks like its the alternator at least in my opinion.

What can happen overtime is that the alternator can fail and the car will rely on the battery to run, therefore draining the battery and causing the car to not start.

Battery should be around 12.6v fully charged, if put on a load test then the minimum should be 9.6v anything close to that I would change...
 

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2011 Tacoma TRD Sport Double Cab Long Box
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I'd bet on the alternator, too...typically brake and battery light on at the same time means that, especially with the voltage drops.

I have an Ultragauge on mine and while the car is running the voltage typically stays between about 14.1 and 14.3...sometimes it will go as high as 14.6 for a brief period of time.

If you want to check something easy and cheap, see if the belt slipping. I don't think that's it in this case, but it can't hurt to look. The H6 has an automatic tensioner so it shouldn't feel loose at any time. Thing is, you'd probably notice it in your power steering and A/C too (the H6 has one belt that handles everything).
 

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'14 3.6R Outback
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How would one determine if the belt is slipping?
Your belt should have no cracks or look worn. When you twist the belt with you hand it should be very difficult to turn it 90 degrees.




Alternators can fail slow. In fact that is very normal. They only time they fail catastrophically is if a bearing goes inside it. It is very likely your alternator is bad. As always double check all your connections and grounds just to sure. It would be silly to drop good $$$ on a part and not check the free stuff. I've done that too.
 
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Discussion Starter #6
Thanks for the replies.
I guess it could be a loose connection too but since it one time the alternator was working then stopped when the car was sitting still I doubt it.
 

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Alternators can partially fail - a blown diode will do it. There are, I believe, 6 in a normal alternator. One bad diode can cause a light to go on but still put out decent voltage. It's probably replacement time. One thing you can do is take the alternator into Vatozone and Advance/Retreat and they will check it for you on their testing bench.

Good luck.
 

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Lawn ornament XT
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The alt in my '98 failed exactly the way you describe. On for a bit, off for a bit. Over a 3 day, 300 mile trip it gradually got worse. Replacement was great, needed no further action.
 

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2003 OBW 2.5L 4EAT
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Just out of curiosity, how many miles do you have on the Outback?
 

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2013 2.5i Premium 6mt, Twilight Blue
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Alternator is probably on its way out and is something you should address now. In my old car I had the same symptoms - intermittent battery light on the dash for a few weeks. I ordered a remanufacturered alternator and was ready to make the swap on the weekend..but then the battery light came on steady on the Wednesday before, at which point you MUST stop the car because the battery is not being charged. I ended up pulling into a park parking lot and doing the swap there the next morning, so it actually ended up O.K.

But lesson learned...as soon as you see the battery light, get on the problem immediately or you could be stranded somewhere.
 
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