As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6467 - PHF-IAD - DURING TAXI FLIGHT, AIRCRAFT RETURNED TO GATE DUE TO EMERGENCY EXIT LIGHT INOP. MAINTENANCE INSPECTED AND REMOVED AND REPLACED BATTERY PACKS, OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)