As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING OUT OF 12,000 FT & 290KTS WITH THE AUTOPILOT ON, RECEIVED STAB & MACH TRIM CAUTION MSG AT THE AUTOPILOT. DISCONNECTED, RAN QRH & WERE ABLE TO RE-ENGAGE THE STAB & MACH TRIM, AS SOON AS WE TRIED TO TRIM THE ACFT THE STAB & MACH TRIM DISENGAGED.