What was found
ON INITIAL POWER UP AFTER STARTING APU AND TURNING ON PACKS BOTH PACK FAIL LIGHTS ILLUMINATED & LAV SMOKE ALARM SOUNDED. F/A NOTED SMOKE SMELL IN CABIN. COULD NOT DUPLICATE PAC FAIL. NO DISCREPANCIES IN AIR CONDITIONING SYSTEM, GASPER FANS, APU BLEED, CROSS BLEED. OPERATIONAL CHECK GOOD. NO FURTHER BURNING SMELL.