Low battery: Check the alternator belt tighness. And take apart and clean the battery terminals.
I have a 1989 Camry. About 6 six ago, the battery voltage was about 9
> volts. After a jump, it was ok until a day ago when it was dead
> entirely.
>
> In both cases, it had last been driven 2-3 days before. Today, the
> battery passed a load test.
>
> Resistance between the positive battery lead and chassis is around 2
> M-Ohms.
>
> The charging voltage while the engine runs is around 13.5 to 14.7 volts
> and down to 12.5 to 13.5 with as much electrical load as I can draw from
> the car lights, blower, windows, defroster, moon roof.
>
> What causes should I consider?