What was found
RIGHT FMC FAILED TWO TIMES, ONCE JUST AFTER LEVEL OFF AND AGAIN DURING APPROACH. RECOVERED ITSELF. GROUNDED-YES. ACCOMPLISHED GVI FMCS CMPTR 2 C/B WIRING BEHIND P6-1, REF B737-800 WDM 34-61-11. REMOVED FMC 2 & CHECKED D3261C, PIN 7 & 8 SHOWS 0 OHM TO GROUND, PIN 1 SHOWS 116 VAC. REMOVED & REPLACED FMC 2, REF B737-800 AMM 34-61-02. ACCOMPLISHED FMC SOFTWARE CROSSLOAD, PER AMM 34-61-00-470-806 & PERFORMANCE FACTORS ADJUSTMENT ,REF AMM 34-61-00-800-801. GROUND VERIFICATION TEST NORMAL, REF AMM 34-61-00-710-801. VERIFIED ALL SOFTWARE CORRECT PER AIPC. PULLED & RESET 2 TOTAL C/BS. TRAX SHOWS, FMC 2 (S/N 013772) HAD PRIOR HISTORY (DUAL FMC FAILURE AT 36000', VTK/MAP FLAGS TOOK 2 MINUTES TO RESTORE).