Nissan Repair: battery, electrical load, load test

Question
i replaced the alternator and now the battery want hold charge had it checked and says its a good battery

Answer
Chris,

If the alternator was replaced and the battery is now going dead would lead me to think a wire is hooked up wrong, a fuse is blown, or the replacement alternator is defective.  I would go to Autozone or Checker, with the car, and have them do an electrical load test to see what the charging system is doing.