As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE TROUBLESHOOTING MEL CONTROL NR M607-4435 FOUND WIRE BUNDLE TO FE PANEL LIGHT CONTROL PANEL BETWEEN P1-299 AND R5-299 CHAFED THROUGH CAUSING ELECTRICAL ARCING ON OUTFLOW VALVE CABLE. REPAIRED WIRES L3850C22 AND L725B22 PER MM 20-30-13. OPERATIONAL CHECKS OK. (M)