As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON RECALL L PACK LIGHT ILLUMINATED EXTINGUISHED UPON RESET. GROUNDED - YES. PERFORMED B737-900 FIM 21-62 TASK 801-BITE PROCEDURE ON LH PACK, TEST PASSED NO FAULTS. FOUND FAULT CODE 21-51266 AND 21-51267 IN FAULT HISTORY. FOLLOWED FIM 21-62 TASK 874. REMOVED AND REPLACED LH TEMP CTRL VALVE. PERFORMED OPS CK, AND LEAK CK GOOD. REF B737-900 AMM 21-51-10/401.