As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAKEOFF CLIMB LT PACK OFF ANNUNCIATOR COMES ON FIRST FOLLOWED BY LT ENG BLEED OFF ANNUNCIATOR. GND OPERATIONS CHECKED LT ENG PNEUMATIC SYS. PNEUMATIC SYS CHECKED OK. OPERATED LT PACK. OPERATIONS CHECKED OK, NO DEFECTS NOTED AT THIS TIME & NO LT PNEUMATIC HISTORY IAW AMM 21-51-00, AMM 36-11-00 & AMM 71-00-00.