What's the voltage accross the battery when the car is running?
If its well below 14V the alternator is not charging the battery properly.
If voltage carries on dropping with the car running, then the alternator is not working properly and you are just running on battery power for a few minutes until its drained.
A battery left for a month run down to zero capacity is probably badly sulphated and may not be able to recover much of its original capacity even when 'fully charged'.
When my battery was on its way out I had similar warnings and error codes all over the place, ABS, Transmission, etc. It was so sulphated it charged up to apparently full in 1 hour (for a 95Ah battery), and promptly quickly died again standing for just a day.
Last edited by Goran; 31st March 2015 at 11:07 AM.
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