As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: LEFT PACK LIGHT ILLUMINATED IN FLIGHT RAN THE QRH PROCEDURE AND LEFT PACK WAS SHUT DOWN. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT PHX. REPLACED LEFT HAND PACK CONTROLLER. PER BMM 21-61-20. BIT AND OPERTIONAL CHECK OF LEFT HAND PACK GOOD.