As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLT - FLT 1840 ON CLIMBOUT FROM CLT, EN ROUTE TO EWR, CAPTAIN REPORTED THE LEFT IRU FAULT LIGHT ILLUMINATED. FLIGHT RETURNED TO FIELD AT CLT AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE REMOVED AND REPLACED THE NR 1 IRU AND ACCOMPLISHED A SATISFACTORY FUNCTIONAL TEST.