What was found
ON CLIMBOUT PASSING THROUGH 10,000 FT CREW HAD A FWD CARGO FIRE HEAT. PUSHED FLASHING DISCHARGE SWITCH AND DID AN EMERGENCY RETURN FULL STOP TO DFW. COMPLETED QRH RED TABS FIRE WARNING WAS OUT PRIOR TO LANDING. AFTER BLOCK IN OF AIR TURN BACK MSC WAS CHECKED FOR FAULTS, NO FAULTS FOUND. REMOVED AND REPLACED MSC IAW AMM 31-42-01-4.OP'S CK GOOD.REF WRI 31-41/0594. ACCOMPLISHED EA 8-2610-73820, INSTALLING A DIODE AND MOD BLOCK TO SEPERATE UPPER AND LOWER CARGO FIRE WARNING SYSTEMS. OP'S CK GOOD. REMOVED AND REPLACED NR 1 CARGO FIRE BOTTLE IAW AMM 26-22-01-4. OP'S CK GOOD. REMOVED AND REPLACED ALL 4 FWD LWR CARGO SMOKE DETECTORS IAW AMM 26-14-01-04. OPS CK GOOD.