As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAD/CHO - FLT 6558 - DURING CRUISE AT 2225 HOURS ON 11-25-98, AIRCRAFT MADE AN UNSCHEDULED LANDING DUE TO LEFT ESS BUS FAILURE. AIRCRAFT RETURNED TO GATE WITH NO FURTHER PROBLEMS. MAINTENANCE INSPECTED AND REMOVED AND REPLACED LEFT PDU. OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FROM RETURN TO SERVICE. (X)