Subaru Outback Forums banner
  • Hey everyone! Enter your ride HERE to be a part of December's Outback of the Month Challenge!
1 - 6 of 6 Posts

·
Registered
Fresh Out of Outbacks!
Joined
·
14,499 Posts
check the grounds and cable integrity. Wires not able to deliver power is as bad as no alternator producing power. If you're sure the alternator is good start cleaning contacts.
 

·
On the Super Mod Squad
2002 3.0 VDC Wag + 2018 2.5 Leg Ltd
Joined
·
27,171 Posts
age of the battery cables / terminal ends?

might be some other short or bad wire too,...or engine grounds.

alternators can test good as they are working the moment it is being tested. ...and then start to not charge the next minute.

@plain OM might suggest a course of action. (or a thread about ideal diagnostic procedures, that I should put a sticky on )
 
  • Like
Reactions: Ozmosis

·
Registered
Joined
·
19,528 Posts
hi I have a 2002 outback the brake battery and abs lights go on and off while driving the alternator tested good battery is new
How was the alternator tested? Removed and tested in a bench setup, or some measurements while the engine was running?

That combination of lights happens, as others have mentioned, when the alternator stops working. The fact that the lights go on and off indicates the cause is intermittent. Unless they always go on and off in a regular pattern that can be repeated at will, testing on a bench or while the car is stopped might not provide an instance when it's not working. Consequently, it tests good, but that's while it's working!

More details on the car might be useful -- model, engine (4 or 6, turbo), transmission, mileage. How old is the alternator, and is it a genuine Subaru alternator (original, replacement) or perhaps an aftermarket one from a parts store?

Bad connections, or wiring, could cause this type of symptom as well, but depending on the age etc, the light symptom does suggest a failing alternator.
 

·
Registered
2017 Outback, 2.5L, Auto; 2018 Forester, 2.5L, Auto (for Mama); 2005 Baja, 2.5 Turbo, Manual
Joined
·
803 Posts
Like raster said, check grounds. On my older cars, I add ground wire from the alternator case to the battery ground strap bolt.
 

·
Registered
Red 2002 AT Outback, Red 2003 Forester, Green 2006 outback All stock, 2006 not running
Joined
·
6 Posts
Like raster said, check grounds. On my older cars, I add ground wire from the alternator case to the battery ground strap bolt.
After checking and re-grounding, I have used dielectric grease to help keep out moisture and corrosion. CRC grease is my favorite. I will be checking all the grounds on my new-to-me 03' Forester.
 
1 - 6 of 6 Posts
Top