the battery was not holding a charge. i replaced the battery. after a few days of using the truck the battery would be dead. i replaced the alternator as well. the battery will still run down. i had the alternator and battery checked. they were both good. the battery will still run down after a few days. do you think that a short is in the system. and how would i check for the short. i had a mechanic tell me that the positive battery cable may cause this problem. is this possible