As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FMC WOULD NOT ACCEPT DATA IN MCDU. GROUNDED - YES. PITOT PROBE HEAT WAS LEFT ON FROM PREVIOUS FLIGHT. ONCE SHUTDOWN AND COOLED OFF THE FMC ACCEPTED ALL ASSOCIATED DATA. PERFORMED GOOD OPS TEST OF FMCS PER B737-800 AMM 34-61-00-710-801.