As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INTEGRATED STANDBY UNIT BEGAN TO INDICATE PITCH UP TO 90 DEGREES NOSE UP AND ROLL INVERTED WHILE ON DESCENT TO RDM. FLIGHT DIVERTED AND LANDING UNEVENTFUL. REMOVED FROM SERVICE. REMOVED AND REPLACED ISI IAW AMM 34-12-16-000-801, AND 34-12-16-400-801. PERFORMED AN OPS TEST IAW AMM 34-12-16-710-801. OPS TESTED GOOD. PITOT STATIC LEAK CHECKED GOOD IAW MTC 6341102. RETURNED TO SERVICE.