As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEG FLIGHT 2303: AS POWER LEVERS WERE ADVANCED TO TAXI, -OSG ABORT- MESSAGE FOLLOWED BY -POWER PLANT- MESSAGE APPEARED ON ED. MAINTENANCE FOUND OVERSIZED GOVERNOR TEST SWITCH STICKING. REMOVED AND REPLACED TEST SWITCH IAW MM 20-30-07. SWITCH OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.