As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS TAKE OFF WARNING SOUNDED ON T/O AT POWER UP. CLEARED RUNWAY AND CHECKED CONFIGURATION, ALL NORMAL. T/O WARNING WOULD NOT REPEAT. MAINTENANCE PERFORMED TAKE OFF WARNING SYSTEM TEST IAW AMM 31-51-00-730-803. A/C OK FOR SERVICE IAW AMM 31-51-00-730-803.