As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MACH TRIM FAILURE ANNUNCIATOR ON RECALL AFTER ENGINE START. CANCELS ON MASTER CAUTION RESET. ACFT GROUNDED. FOUND AFCS SYSTEM A CANCEL EXC AC BRAKE OPEN ON PA18-1 PANEL. RESET THE CIRCUIT BREAKER IAW AMM 20-60-1. PERFORMED BITE CHECK MACH TRIM SYSTEM IAW AMM 221-11-00-740-806. MACH TRIM SYSTEM OPERATIONAL CHECKED GOOD.