What was found
SPS - FLT 3512 - CREW REPORTED EMERGENCY LIGHTS IN CABIN ARE INOPERATIVE. MAINTENANCE REMOVED AND REPLACED POWER SUPPLY UNITS 20LN, 21LN, 22LN, 23LN, AND 24LN. OPS CHECK WAS GOOD AND AIRCRAFT WAS RETURNED TO SERVICE. REF SIMA200124501. (M)