What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On 10/07/11 Cessna 525C was on descent from FL270 to 220 when a cyan cas message "retrim left wing down" was observed. The aircraft would not trim in either direction. After disconnecting the autopilot, the aircraft pulled hard to the right, causing the pilot to use flight controls to keep aircraft level. The pilot diverted to Modesto, CA. Where he landed the aircraft safely with no injuries or damage to the aircraft.
As the FAA filed it
ON 10/07/11 CESSNA 525C WAS ON DESCENT FROM FL270 TO 220 WHEN A CYAN CAS MESSAGE "RETRIM LEFT WING DOWN" WAS OBSERVED. THE AIRCRAFT WOULD NOT TRIM IN EITHER DIRECTION. AFTER DISCONNECTING THE AUTOPILOT, THE AIRCRAFT PULLED HARD TO THE RIGHT, CAUSING THE PILOT TO USE FLIGHT CONTROLS TO KEEP AIRCRAFT LEVEL. THE PILOT DIVERTED TO MODESTO, CA. WHERE HE LANDED THE AIRCRAFT SAFELY WITH NO INJURIES OR DAMAGE TO THE AIRCRAFT.