As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB OUT THROUGH NFL280 VNAV DISCONNECTED. WE RECEIVED "VNAV INVALID PERF" MESSAGE ON FMC. AFTER RE-ENTERING THE COST INDEX VNAV RETURNED TO NORMAL. GROUNDED - YES. ACCOMPLISHED DFCS BITE REF B737-900 FIM 22-11 TASK 801 CNL A & B FAULTED LAST LEG 22-11822. ACCOMPLISHED FIM 22-11 TASK 811 DFCS CURRENT STATUS PASSED NO FAULTS. ACCOMPLISHED FMC BITE NO LAST LEG FAULTS OR FAULT HISTORY IN BITE A & B REF FIM 34-61 TASK 8010.