As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, FLIGHT NR 6940 FROM CLE TO AVP DIVERTED TO IAD AT 0600 HRS, DUE TO THE RT ENGINE FUEL FILTER BLOCKED CAP LIGHT ILLUMINATING. AIRCRAFT LANDED AT IAD WITH NO FURTHER INCIDENTS. MAINTENANCE REPLACED THE FUEL FILTER. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (Z)