As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON TOUCHDOWN R AC BUS DE-POWERED R GEN CONTROL SWITCH "OFF" LEGEND WAS ILLUMINATED. BPCU PER FIM 24-20 F/T 801, TEST OK. REMOVED AND REPLACED BUS POWER CONT UNIT, PERFORMED RT ENG GEN TEST IAW AMM 24-11-01 AND PERFORMED BPCU BITE TEST IAW AMM 24-22-00. OPS CHECKED GOOD. THIS CLEARS MDDR 127770.