As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PACK LIGHT ON RECALL. ACFT GROUNDED. WHILE RUNNING THE LT PACK, A LOUD IRREGULAR NOISE WAS COMING FROM THE LT PACK ACM. PERFORMED A BITE TEST OF THE NR 1 TEMP CONTROLLER AND VERIFIED THE EXHAUST SRADA FAULT. REPLACED THE EXHAUST SRADA IAW AMM 21-51-27/401. OPS CHECK GOOD.