Check engine light, open door light, and batterie light all came on and won't go off?

2000 Honda Odyssey I already had the altinator replaced it a month old. The batterie almost a year old. Would the belt need be changed or something else?

Changing the belt won't help the door light. Why have you not gotten the code read? Just in case there's a code wouldn't you like to find out. And to check the output of the alternator is not a dirty job, you only need a volt meter. Now do some work of your own and then come back if you don't learn anything.