The outage, which left 5,461 customers in the dark, affected areas of San Leandro, east San Lorenzo, and the Ashland area of Hayward, and it began around 12:26 a.m., PG&E spokeswoman Jana Morris said.
Crews determined that an underground piece of equipment was to blame, and they replaced the part, Morris said. All customers were back online at 1:48 a.m.