My neighbor had to go through 3 new Autozone batteries before he got a "good"
one. Same symptoms as yours. On my Mitsubishi van with idiot lights my wife
got stranded at a shopping mall with adead battery. Got it home and had my
FLAPS check the battery and alternator. Both checked good. Happened again a
week later. Replaced the battery. A week later, slow starting indicated a
weak battery. Charged it and took the car to the FLAPS to again check the
battery and alternator. Both OK. This went on for a while because I didn't
want to cough $149 for a puny Japanese rebuilt. Finally took it to an
alternator/starter shop and they found a bad diode. $45 later I had new
diodes and brushes and it works fine. The "idiot lite" never gave a clue that
the alternator had a problem. Double check the alternator.

Ken Hunter
82 Westy 1.9D
84 Jetta 1.5D
89 Mitsubishi van