Power was restored at 3:45 p.m. to the last pocket of Hawaiian Electric Co. customers in the Pearl Ridge area affected by an outage.

The outage disrupted service to about 900 total customers from about 10:30 a.m. but power was restored to most of them by 1 p.m., said HECO spokesman Darren Pai. The last group included businesses and some apartments, Pai added.

Cause of the outage is under investigation.