As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI, C/L IRS DC FAIL EICAS MESSAGE ILLUMINATED. AIRCRAFT RETURNED TO BLOCKS (BTB). CYCLED STANDBY POWER, PER AMM 24-33-00 AND PERF OPS CHECK OF L AND C IRS PER IAW FAULT TREE 34-21. PS CHECK GOOD, A/C REMAINS CAT IIIB. ONE TIME AUTH # 2025-047. AIRCRAFT RETURNED TO SERVICE.