Authorities say a blown junction caused a temporary outage in Pasadena, but power had been restored to all but three customers.
Crews Tuesday were responding to reports of a vault explosion that occurred on campus at UCLA.
A transformer failure in Fullerton Saturday left nearly 1,900 Southern California Edison customers without power.
Officials said one person was killed Monday afternoon in an underground vault explosion.
An explosion reported at an underground vault in Encino has left hundreds of people without power.
A vault fire and explosion in northern Anaheim knocked out power to the area on Friday afternoon.