OK - I'm at my wit's end! Please excuse this lengthy explanation in advance - here's the story:
Just bought our first Subaru ever - 1997 Legacy Outback 2.5L with 185K miles - from a used car lot. The dealer had a local shop go over it to make sure there were no "big" problems. Everything seemed to work fine, just some cosmetic flaws from a baseball-size hailstorm we had here at the end of June. (The perfect car for my teenage son to drive.)
Within a week, he started having to jump-start it almost every time he stopped somewhere. After some messing around at home, we jumped it and took it to a parts store for a free charging system check. They said the battery was fine (just a bit low), but there was no charging voltage out of the alternator.
So we bought a "new" remanufactured alternator from our local Subaru dealer and installed it. I don't think we checked the alternator output / charging voltage right away - we stupidly assumed that the problem was fixed. Ha! Within a week, again, my son was having to jump-start the car every time he stopped anywhere. (Luckily, we live where everyone's a Good Samaritan and it's easy to get help.)
We thought maybe the battery was just too deeply discharged for the alternator to recharge it during his quick trips around town. So we put the battery on a trickle charger overnight, put it back on the car the next morning, and sent him off to school. After just a few trips around town, the battery was dying again. We spent a couple of weeks screwing around with it again - checking connections, ground continuity, etc. Finally took it to have a battery check again and got the same story - battery was fine, alternator was not charging. This time we decided to make sure it was a bad alternator - we took it out of the car and had the local NAPA store bench-test it for us. Result = no DC charging voltage = bad alternator.
So we took the "new" alternator back to the Subie dealer and did a warranty swap for another "new" alternator. We stopped on the way home and had it bench-tested at NAPA just to make sure it was good - according to their test, it was. We installed it last night, turned the car on, checked the charging voltage, and NO CHARGING VOLTAGE AGAIN!!!
I have checked and double-checked every ground connection in the engine compartment - all fine. I have tested the continuity on the battery to alternator cable - it's fine. I checked for a short between the two contacts on the alternator harness/connector - not even a highly-resistive short. I have checked the voltages on the alternator connector with the key switched on (engine not running) and get about 12V across the board - same as battery - normal, I think? But when the engine is running, the alternator output to the battery reads the same voltage as the battery (slightly lower than it tested right before I started the engine) - between 12.2 and 12.8V, depending on how many times I've started it since the battery was charged - and it's dropping.
The battery / charge indicator light (and all other idiot lights) comes on when the key is switched on and immediately goes off when the car starts, as if there's nothing wrong with the charging circuit. The CEL has come on a couple of times over the past month, but just for a short time and then goes back off. (It has also been reset repeatedly from disconnecting the battery for charging.)
HELP!
Just bought our first Subaru ever - 1997 Legacy Outback 2.5L with 185K miles - from a used car lot. The dealer had a local shop go over it to make sure there were no "big" problems. Everything seemed to work fine, just some cosmetic flaws from a baseball-size hailstorm we had here at the end of June. (The perfect car for my teenage son to drive.)
Within a week, he started having to jump-start it almost every time he stopped somewhere. After some messing around at home, we jumped it and took it to a parts store for a free charging system check. They said the battery was fine (just a bit low), but there was no charging voltage out of the alternator.
So we bought a "new" remanufactured alternator from our local Subaru dealer and installed it. I don't think we checked the alternator output / charging voltage right away - we stupidly assumed that the problem was fixed. Ha! Within a week, again, my son was having to jump-start the car every time he stopped anywhere. (Luckily, we live where everyone's a Good Samaritan and it's easy to get help.)
We thought maybe the battery was just too deeply discharged for the alternator to recharge it during his quick trips around town. So we put the battery on a trickle charger overnight, put it back on the car the next morning, and sent him off to school. After just a few trips around town, the battery was dying again. We spent a couple of weeks screwing around with it again - checking connections, ground continuity, etc. Finally took it to have a battery check again and got the same story - battery was fine, alternator was not charging. This time we decided to make sure it was a bad alternator - we took it out of the car and had the local NAPA store bench-test it for us. Result = no DC charging voltage = bad alternator.
So we took the "new" alternator back to the Subie dealer and did a warranty swap for another "new" alternator. We stopped on the way home and had it bench-tested at NAPA just to make sure it was good - according to their test, it was. We installed it last night, turned the car on, checked the charging voltage, and NO CHARGING VOLTAGE AGAIN!!!
I have checked and double-checked every ground connection in the engine compartment - all fine. I have tested the continuity on the battery to alternator cable - it's fine. I checked for a short between the two contacts on the alternator harness/connector - not even a highly-resistive short. I have checked the voltages on the alternator connector with the key switched on (engine not running) and get about 12V across the board - same as battery - normal, I think? But when the engine is running, the alternator output to the battery reads the same voltage as the battery (slightly lower than it tested right before I started the engine) - between 12.2 and 12.8V, depending on how many times I've started it since the battery was charged - and it's dropping.
The battery / charge indicator light (and all other idiot lights) comes on when the key is switched on and immediately goes off when the car starts, as if there's nothing wrong with the charging circuit. The CEL has come on a couple of times over the past month, but just for a short time and then goes back off. (It has also been reset repeatedly from disconnecting the battery for charging.)
HELP!