We never unhooked the battery the replace the alternator as it was run down do to the alternator failing in the first place. So we hooked a jump box to the car and tried starting it that way. You could hear the starter clicking but it wouldn't start and the horn honked and the lights came on. I read about this happening to somebody else and they said a computer reset worked but I don't know how to go about doing this? You just undo the battery for a half hour and hook it back up?