As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FO AUTO PILOT IN USE 1.5 HOURS INTO FLT, FO FMC FAIL VTRK INDICATED. GROUNDED - YES. SWITCHED TO CA AUTO PILOT AND FMC RETURNED TO NORMAL OPS BEFORE WE COULD RUN QRC. SWITCHED BACK TO FO AP AND OPS CKS GOOD. BOTH FMCS NORMAL ON POS PAGE 3 FMC SELECTOR REMAINED IN NORMAL THROUGHOUT FLIGHT.