As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"VNAV INVAL ID-PERF" MESSAGE ON SCATCH PAD WITH LOSS OF VNAV, BUT RESET AFTER ENTERING CNT INDEX. GROUNDED - YES. ACCOMPLISHED B737-900 FIM 22-11 TASK 801 DFCS BITE, WITH NO FAULT ALSO ACCOMPLISHED FIM 22-11 TASK 811 INITIAL EVALUATION WITHIN NO CURRENT FAULTS. ACCOMPLISHED ADIRU BITE PER FIM 34-21 TASK 801 ALL TESTS PASSED.