As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING AFTER START CHECKLIST ON # APR RECALL BOTH SPEED TRIM FAIL AND MACH TRIM FAIL LIGHTS ILLUMINATED. GROUNDED - YES. PERFORMED B737-900 FIM 22-11 TASK 849 FOUND FCC A INOP , RESET BOTH FCC'S PERFORMED BITE TEST 60.32 AND REPAIR VERIFICATION, ALL FAULTS CLEARED TEST RESET.