As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
L NAV WOULD NOT ENGAGE . SELECTED A DIFFERENT DEPARTURE L NAV ENGAGED. GROUNDED - YES. PERFORMED FIM 22-11 TASK 830, VERIFIED CORRECT FLIGHT PLAN WAS ENTERED. L NAV NOW ENGAGES, NO FURTHER MAINT ACTION REQUIRED VERIFICATION SUCCESSFUL.