What was found
UPON ROTATION SMOKE LIGHT ON MWP ILLUMINATED. ON SECOND OFFICER'S PANEL R2 LIGHT FOLLOWED BY R4, R5, L3, & L5. THEN DURING DOWNWIND, ALL LIGHTS WENT OUT. NO SMOKE FOUND IN CABIN. RAN PACKS AND COOLED CABIN OFF. CABIN SMOKE DETECTION SYSTEM OPS CHECKS NORMAL IAW M/M 26-14-00. NO DEFECTS NOTED.