Charging System

Car died while my sister was driving to work. I jumped started the car and took it to a automotive store. They charged the battery and said the battery was good. The car made it to her house about two miles and would not start the next day. She had her neighbor jumpstart the car and took it back to the autoparts store where the tested the alternator and battery while in the car. There test indicated the alternator was not charging properly. I removed the alternator and had it tested while out of the vehicle. The alternator tested just fine.

I noticed while removing the alternator there was a large 14mm bolt on top of the alternator contacting the alternator it was practically fallig out. I tightened the bolt. I then noticed the belt for the alternator was extrememly worn and cracked practically all the way through. I replaced the belts reconnected the alternator. Replaced the negative ground wire, which was missing the bottom half o fthe insulation and was extremely corroded on the battery. I checked the fuses for the alternator and the main fuse. They are all in proper working order.

I then had the battery tested again since it was not holding a charge and was corroding the negative terminal again. the battery tested in good condition. The civic is still not holding a charge. Any suggestions?

Is there a simple way to check for a power drain?