As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAX - CREW REPORTED DURING CLIMBOUT SMOKE IN THE AFT CABIN AREA. AFTER CAPTAIN RESTARTED THE APU THERE WAS VISIBLE SMOKE IN THE COCKPIT AS WELL. EMERGENCY DECLARED FLIGHT RETURNED LAX LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED RIGHT AUGMENTATION VALVE AND LEFT PACK PRESSURE REGULATOR. SYSTEM GROUND CHECK NORMAL OPERATION.