As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LH PACK LIGHT ILLUMINATES ON RECALL. RESETS WITH MASTER CAUTION RESET. GROUNDED - YES. PERFORMED LH PACK/ZONE TEMP CONTROLLER BITE TEST PER B737-900 AMM 21-61-00. BITE TEST REVEALED LH TEMP CONTROL VALVE FAILURE. REMOVED AND REPLACED LH TEMP CONTROL VALVE PER AMM 21-51-10. BITE TEST GOOD. OPERATIONAL TEST GOOD. LEAK CHECK GOOD. THIS CLEARS MEL 21-32B.