What was found
ON FINAL FOR KMEM 18L AT 3000 FT, WE PUT THE GEAR HANDLE DOWN AND RECEIVED 4 RED GEAR UNSAFE INDICATIONS. WE EXECUTED A GO AROUND TO REENTER THE PATTERN AND RAN THE GEAR UNSAFE INDICATION WITH GEAR HANDLE DOWN CHECKLIST. AFTER RUNNING THE CHECKLIST WE WERE ABLE TO GET A 4 GREEN INDICATION. DECLARED EMERGENCY LANDED UNEVENTUALLY. TROUBLESHOOTING PERFORMED REF MD10-30- FIM REF TO 32-30-00-2 FOUND NO CURRENT OR PAST FAULTS ON PSCU. ALSO PERFORMED PIN PROGRAM OPTION PER MD10-30 FIM 32-30-00-2 PER TABLE 202 FOUND NO FAULTS. ALSO NO ISSUES WITH GEAR HANDLE. DID JACK A/C AND PERFORMED NORMAL GEAR OPERATION VARIOUS TIMES PER MD10-30 AMM 32-30-00-5 NO FAULTS NOTED. DID REPLACE A/C PSCU AS AN PERCAUTIONARY REF TO MD10- 30 AMM 31-71-01-2 AND OPS CHECK NORMAL RTS SYSTEM ALSO CHECKS NORMAL THIS TIME. OK FOR SERVICE. ( PSCU , ELDEC CORP P/N 8-946-01 S/N A82).