As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MIA FLT NR 9241 MIA-PHL - AFTER TAKEOFF, CREW RECEIVED EICAS MESSAGE OF AIR/GRND DISAGREE. FLIGHT RETURNED TO MIA WITHOUT FURTHER INCIDENT. MAINTENANCE REPAIRED WIRE W840-203B-18, BETWEEN CONNECTOR D4302J AND D5554J. SYSTEM OPS CHK NORMAL.